The Performance Digest - April 2022 (Issue 66)

Study Details

How to Read Me!

Praccal Takeaways from study

Related links to learn more about the topic

Reviewers comments on the st udy

Research Reviewers

The Science of Coaching

Will is a Lecturer of Sport Coaching at Deakin University, Australia. Prior to this he has worked with Cricket NSW and Cricket Australia in an array of roles ranging from a sport scientist, development coach and a strength and conditioning coach. He completed his PhD at the University of Newcastle, Australia within the area of practice design.

Youth Development

Tom is the Head of Athletic Development at St Peters RC High School. He holds a Masters in S&C and has previously worked with West Bromwich Albion FC, Gloucester Rugby club, and Great Britain Equine. Tom is our youth research reviewer at Science for Sport.

Strength & Conditioning

James is currently the Head Strength & Conditioning Coach for the Romanian Rugby Union. He has previously worked in America's professional rugby competition Major League Rugby with Austin Elite and the NZ Women’s National Rugby League Team. He is a published author and has completed a MSc in Sport & Exercise Science from AUT, Auckland, NZ.

Technology & Monitoring, The Science of Coaching, S&C

Cody is a strength and conditioning coach and adjunct lecturer at the University of Iowa. He has an MSE in Exercise Science from the University of Kansas and also holds a CSCS from the NSCA.

Nutrition

James is a Performance Nutritionist for the English Football Association and works alongside the England national teams (men's and women's). He is also a SENr registered performance nutritionist and holds a PhD from Liverpool John Moores University.

Matthew is a Physical Therapist and the Clinical Director at a private Physical Therapy clinic in NYC. He has a special interest in the treatment of lower extremity/foot and ankle injuries along with helping runners and walkers to get back to what they love to do.

Dr. Will Vickery PhD

Tom Green MSc UKAD Advisor

James de Lacey MSc

Dr. James Morehen PhD

Cody Roberts MSE

Matt Klayman’s MSE

Fatigue & Recovery, S&C

COACHING What actually goes on?

A look into the real world of coaching

Despite the greater volume of research and access to information within the world of coaching in recent times, there still remains a debate about what coaching is and what it entails (or what it should entail if reading some research).

The profession of coaching has been around for much longer than the research that looks to explain it, with each coach and the environment they perform in different from the next, highlighting the importance of context. As Santos and Jones suggest, this point is often lost amongst the research, with much of the research disregarding “how coaching plays out as situated action” (see for original reference, p 201). HERE

Much of what has been published regarding the practice of coaches has focused on and looked to explain specific aspects of coaching (e.g., how they make decisions, the relationships they have with their athletes), as opposed to simply observing and examining what goes on. Within the current study, the authors instead have decided to focus on the ‘whatness’ of coaching, exploring what it is coaches do, particularly the minor, everyday actions of the coach, and how each of these influence and interact with each other.

The setting for this study was a national level women’s basketball team that comprised 15 players and five staff. With regards to the coaching staff, this included a head coach (age = 30 yr; years as head coach = 7 yr) and two assistant coaches (age = 25 yr and 28 yr).

Over the course of six months, the lead author completed ethnographic-based research that included informal interviews with various participants. In addition to this, the lead author was also immersed in the team and club environment (e.g., took part in competition preparation, present at meetings with the coaches, and sold club merchandise) to provide them with more opportunities to take part in contextual interactions.

Practical Takeaways

As stated by the authors, “the creation of ‘charming’ personas” by the coaches to convince the athletes that working together each and every training session, was something readily used. The idea of a ‘charming’ personality can often be associated with negative connotation, however, in this context, this is not the case. Coaches looking to gain ‘buy-in’ from their athletes need some level of charm to their personality and the way they approach building a relationship with athletes in order to gain their trust. Keep in mind that how one coach displays charm may be different to another.

The coaches appeared to have the best interests of their players at the forefront of their minds. Regardless of the level of sport being played, being aware of what your athletes need, whether technically, tactically, or mentally, should be a priority for any coach. This can be displayed in many ways,

but the more impactful behaviours and actions are likely to be the less eventful, the ones that happen all the time without giving them any thought (e.g., having a laugh at something together, handing out a high-five).

Another recommendation by the authors that would assist those wanting to improve their coaching skills, is related to coach education. Even if not provided or encouraged by an official coach education, coaches should look to reflect upon how and why they act the way they do and consider why these actions are beneficial and effective whenever they get the chance.

At the completion of the six-month period, the authors provided a picture of what the coaching involved, breaking this into various themes:

We’re all in it together: The coaches often presented an image and behaviours with the aim of gaining ‘buy-in’ from the players. For example, the coach would present himself as someone who would not ask the athletes to do something they weren't prepared to do themselves.

A benevolent ‘head of the family’: Led by the head coach, a family-like environment with the intention of the players to engage with their needs and wants was created, cultivating a message of close relational care.

Caring for “Audrey” (one of the athletes involved): Loyalty amongst the athletes to the coaches was based on the impression that the coaches had the best interests of the athletes at heart.

An enjoyable, meaningful climate: The environment created by the coaches was one which included a range of emotions to be expressed by players and staff alike. A climate that encourages enjoyment and honesty appeared to be something all bought into.

Will’s Comments

“Rarely do we as coaches consider the impact that the everyday things we say or do have on other aspects of our life. This rings true for the sports environment, particularly when focused on coaches. More often coaches are concerned with how the bigger aspects like the types of drills and activities taking place at practice are designed and performed, or what the power dynamic between the coach and their athletes looks like and plays out.

“Based on the findings of this study, we coaches need to consider more about what goes on when we aren't really thinking about what is going on. Gaining the trust of our athletes to the point where they see us and their teammates as part of a family is something gained from the continual addition of the little things rather than a couple of big events.”

How player load metrics can help coaches guide training prescription

OBJECTIVE

Player tracking technology (e.g. Catapult Vector) allows coaches the opportunity to measure, quantify, and understand the physical demands of training and competition. Metrics such as distance covered, speeds achieved, and accelerations or decelerations in three dimensions (i.e. x, y, and z planes) are possible through a microsensor (e.g. accelerometers, gyroscopes, magnetometers) attached to the athlete (see ). Total HERE player load (PLTOTAL) is a popular external load metric, representing a combination of force-vectors (production or absorption) in the anterior-posterior (PLAP), mediallateral (PLML), and vertical planes (PLV, see HERE).

Despite the prevalent use of PLTOTAL, in athlete monitoring for field-based team sports, there has been limited research into the specific directions of force production that occur in elite soccer, as well as any generalisations of PL by position, or interactions with other on-field load measures (e.g. distances, speeds, etc.). In turn, the three-fold purpose of this research on elite soccer players was to examine the influence that each player load metric (PLAP, PLML, and PLV) had on the overall PLTOTAL, identify any potential influence that position has on PL metrics, and explore a potential relationship between distance covered and PLTOTAL.

WHAT THEY DID

Twelve male elite soccer players (26.8±3.8 yr) had inertial tracking data analysed across a total of 13 consecutive matches during the latter portion of their (Spanish LaLiga123) season.

Players were categorised by position (central defender, full back, midfielder, wide midfielder, and forwards), examining distance covered, PLTOTAL, PLAP, PLML, and PLV for each half and match.

Data was analysed to find the influence of PLAP, PLML, and PLV on PLTOTAL, the variance of player position on all PL metrics, and the relationship between PLTOTAL, distance covered, and player position.

Practical Takeaways

Given the association between PLTOTAL and distance covered, coaches can select one of the two measures as a primary objective external load monitoring metric. Pairing the external measure with a subjective internal measure (e.g. rating of perceived exertion) can be a secondary variable to monitor in coordination that adds context (e.g. understanding of an athlete s response or reasoning behind the effort) to the external metric. In order to keep match data comparable, coaches may consider monitoring PLTOTAL or distance covered as a rate (units per minute) based on the number of minutes played by the athlete. This would better help to identify fluctuations in output, whereas if a load value decreased, it could be a sign of fatigue. Alternatively, if we saw an increase in work rate for a given athlete, we would expect an increased rating of exertion and higher need for recovery in the following days, possibly decreasing workload in training to assist the recovery process.

Although PLTOTAL had no relationship with player position in this study, this is dependent upon the specific team and their style of play (see HERE). Identifying any potential differences in these values (e.g. PL, accelerations, decelerations, high speed running, or distance covered) would be important to best prepare athletes for the demands of their given position (e.g. more change of direction work, or more sprinting volume).

With PLV actions in the vertical plane dominating PL metrics, due in large part to the ground reaction force experienced during footstrike when running.

This places a crucial importance in teaching proper running mechanics (minimising vertical displacement), as well as adequate exposure to plyometric training to prepare for competition demands. As well as featuring strength training (e.g. squats, lunges, step-ups) into their ancillary physical development outside of technical and tactical work on the pitch. Even during an in-season period, this work should occur at least once per week in order to maintain vertical force production ability across the season for injury mitigation and performance enhancement.

Although the majority of work was noted in the vertical plane, the measures between PLAP and PLML may occur simultaneously (e.g. sprinting in a curvilinear action) and therefore athletes need to be exposed to maximal speeds and efforts (e.g. accelerating, decelerating, and sprinting) in multiple directions, angles, and patterns instead of simply a straight line with no exposure to the forces experienced through the body (feet, ankles, hips, etc.). By training in this manner, coaches are adequately preparing athletes for the stresses they will experience on the field.

Coaches can monitor an athlete s performance by comparing PL metrics within-player, looking to identify potential fatigue if overall PLTOTAL decreases in competition from week to week. Even going more specific to identify an adjustment in movement strategy, looking specifically at significant changes in PLAP, PLML, and PLV from a specific training session or drill (see to limit the HERE) amount of variability and context expected in a match.

WHAT THEY FOUND

PL in the vertical plane (PLV) was the most dominant plane of movement for PLTOTAL. Player position did not specifically impact PL metrics.

Distance covered in a match was consistently associated with PLTOTAL.

As a coach begins brainstorming training prescriptions for a specific sport and athlete, the first step is a ‘needs analysis’ where the sport itself is analysed. By measuring on field performances with player tracking technology and the ability to identify forces in specific planes of motion, coaches can better understand the specific demands of competition. By doing this, training prescription can be done with more certainty than simply a general program that includes a mix of everything (e.g. running, jumping, and change of direction) for the chaotic combination of all those experiences in sport-specific environment.

“For this research specifically, we see sound support for the importance of a soccer player's ability to generate force in the vertical plane, which includes primarily running, as well as the occasional jump. For a sport that is seemingly played on the ground, players experience a significant load in the vertical plane, as they are striking the ground with each foot contact to sprint down a ball or gain distance from an opponent. This is why vertical force production potential is such a vital piece to speed development. To support durability, the eccentric loading through strength training (e.g. squats, lunges, step ups) and an equivalent volume of running to that experienced in training and competition is necessary to mitigate injury due to overload (chronic or acute). As a physical preparation coach, these measurements provide understanding of competition demands that can guide training means and volumes.”

Strength & Conditioning

This month ’ s top research in strength & conditioning.

WHAT IS THE COMPARABILITY OF RESIS TRAINING RPE WITH OTHER FORMS OF

CAN THE SPANISH SQUAT HELP REDUCE PATELLAR PAIN IN-SEASON?

COMPARING REST INTERVALS IN UPPER BODY STRENGTHENING EXERCISE

IS IT TIME TO RE-THINK THE 7-DAY MICROCYCLE?

What is the comparability of resistance training RPE with other forms of exercise?

OBJECTIVE

Rating of perceived exertion (RPE) is a proven method to quantify internal training load of athletes performing both endurance and resistance training (see An HERE).

athlete’s RPE is a perception of intensity based on effort and the psychophysiological response to a given activity

Research consistently shows correlation with an athlete’s subjective report and objective physiological measures of intensity (e.g. heart rate, oxygen consumption, blood lactate, or percentage of one repetition maximum (%1RM), see ). When applying this method to endurance HERE activities, RPE typically has a linear increase that is consistent with the completion of the task (see HERE). This is due in large part to the distance or duration of the endurance activity and has been explained as teleoanticipation (see HERE), which ultimately influences pacing strategies and associated effort.

Although RPE has proven valid at the completion of a set when resistance training (see ), the ability to apply HERE the concept of teleoanticipation and relationship with task completion to resistance training is undetermined. Therefore, researchers used resistance training to examine a potential relationship between RPE and percentage of task completion, comparing results to previous research regarding aerobic training.

WHAT THEY DID

Twenty-one male athletes (age 22.1 ± 2.3 yr), with at least six months of resistance training experience, assessed their 1RM in both bench press and leg press, subsequently performing a set at 65-%1RM for 12 repetitions while reporting their RPE using a 0-10 Borg Scale for familiarisation.

Across four sessions following, each separated by 72-hr, subjects performed one set to failure at randomly assigned intensities (90-, 78-, 58- and 43-%1RM for leg press, and 87-, 75-, 55-, and 40-%1RM for bench press). Repetition pace was to be kept constant, while the subject reported RPE after each and performed until failure was reached.

Data from all subjects was combined and analysis was performed on the results to identify the relationship between RPE and percentage of task completed based on maximum repetitions in a given set.

A single regression line was created after combining all four intensities and both exercises for analysis and generalisation.

Practical Takeaways

Coaches can use an athlete’s report of RPE as a strategy to monitor athlete-recovery. RPE can be used as feedback for an athlete’s readiness (or recovery status), by comparing a given performance (e.g. repetitions at a given load, or running distance-time measure) with the RPE report following. For example, an athlete who has reduced performance relative to previous efforts and reports a high perception of effort is likely under-recovered, compared with an athlete who is performing well while maintaining a submaximal (e.g. 6-9) RPE.

§ Using this strategy can help coaches to better manage loads across the week, ensuring athletes are recovering prior to a competition and fatigue is resolving as expected.

Use an athlete’s RPE as a means of tracking athlete progress and showcasing performance

improvements. Especially at submaximal (RPE 6-9) intensities, where an athlete’s performance may be similar but their RPE is actually lower. Given the results of this study, this is possible for resistance training as well as aerobic activities.

Implementing an RPE monitoring strategy can be a way to quantify activity intensity and used as a marker of internal load for holistic training management. Especially since RPE is consistent across activity types (e.g. aerobic-, sport-specific-, or resistance-exercise), which is especially helpful for athletes who engage in a range of activities for their training. By doing this, coaches can reduce the likelihood of overtraining or increased injury risk.

The results of this study are a great example as to the ability for athletes to know their physiological limits and should give coaches confidence when prescribing work based on a suggested RPE. For example, if a coach wants an athlete to accumulate multiple sets of sustainable efforts, they will prescribe an RPE of 8 for exercise (running or resistance training) and can confidently prescribe numerous sets (3-5) because the efforts were not maximal, but rather repeatable. This method allows training to be much more productive (improving performance) versus overly fatiguing (decreasing performance).

Coaches can use an athlete s RPE to match the intensity of effort in training with the intended goals of a task or entire session. For example, if an aerobic activity is to be in a steady state, at roughly 60% max heart rate, or a resistance training set is to be roughly 4-5 reps from failure, a coach would suggest an RPE of roughly 6 for the time allotted or set prescribed.

Familiarisation with a given RPE scale (1-10, or 6-20) is critical to an athlete providing valid and reliable insight. Coaches need to take time to teach the relative intensities associated with a 6, 7, 8, 9, or 10. Without this step and understanding, all the above possibilities are lost in translation between athlete and coach.

WHAT THEY FOUND

The relationship between RPE and percent of task completion was linear for the resistance training data collected across all intensities and both exercises - bench press and leg press.

The relationship between RPE and percentage of task completion is consistent with other research related to walking, running, and cycling. Support for both the concept of teleoanticipation presented by Ulmer and the anticipatory-fatigueRPE model presented by Tucker, as RPE and regulation of effort increased as maximal exertion neared.

§ Specifically, RPE was roughly (±1) 3.5 at 20-, 5 at 40-, 6.5 at 60-, 7.5 at 80-, and 9.5 at 100-% of task completion.

“Given the results of this research in combination with other research mentioned throughout, there is a notable and consistent relationship between RPE and percentage of task completion. This not only supports RPE as an accurate measure and representation of intensity, but also offers coaches and athletes a lot of utility in application.

“As coaches teach athletes how to relate the RPE value to a given perception of effort, the athlete begins to understand their boundaries, even expanding the psychological limitations. They may possibly experience that, ‘I never thought I could do that many!’ or ‘I never thought I could hold that pace,’ sensation - and that’s the goal of training, to bring confidence to an athlete’s potential.

“Rating of perceived exertion brings an awareness to the afferent feedback that is associated with sport, training, and exercise, and one of the truest psychophysiological representations of an athlete s output. A valid and reliable RPE from an athlete is an invaluable skill and strategy to coaching and training at a higher level. Not to mention, the cost-effectiveness of implementing RPE as a monitoring strategy; when done right, an athlete s subjective RPE continues to hold up against any technology’s objective measure.”

Can the Spanish squat help reduce patellar pain in-season?

OBJECTIVE

Knee pain, specifically patellar tendinopathy, is common for young athletes of all sports which require jumping and high-impact activities. Common strengthening protocols utilise various programs that progressively load the patellar tendon while reducing pain.

During the season however, athletes who need to travel do not always have access to strength training equipment including a knee extension machine. This article tested outcomes of a single isometric strength training exercise, the Spanish squat, on athletes in various sports. This exercise was used in a setting where gym equipment was not regularly available.

With this, the aim of the study also investigated whether the exercise could assist the athlete in reducing pain during their season.

WHAT THEY DID

The authors recruited 25 athletes from various sports –including Australian football, squash, dance, volleyball and tennis – who were experiencing anterior knee pain.

The pain was diagnosed as patellar tendon pain by a Physical Therapist along with having pain with jumping and or change of direction.

Furthermore, the subjects had to report at least a 2/10 on the Visual Analog Pain Scale with a single leg decline squat pattern. This was utilised to mimic patellar loading and is subjectively painful in this population. The subjects also completed the VISA-P Questionnaire which is used to rate symptoms with knee pain.

The subjects were instructed to complete five repetitions of 30 second isometric repetitions of a Spanish squat for a four-week period. The subjects were asked to complete the exercise daily

WHAT THEY FOUND

The relationship between RPE and percent of task Following four weeks of the intervention, it was found there was a 49% reduction in reported pain with the single leg decline squat and a meaningful change of over 18% is the VISA-P Questionnaire. The subjects reported performing the exercise a median of five times a week. With this study however, there was no control group utilised. This was due to multiple teams denying the request of the authors to participate in a sham treatment.

Practical Takeaways

This paper reviews the effect of an isometric squatting exercise on athletes reporting patellar tendon pain with pain with jumping and changing directions. This exercise was utilised as it requires little equipment with just the use of a rigid mobilisation belt.

The Spanish squat was shown to decrease patellar pain subjectively with a specific questionnaire and single leg squat pattern when used over a fourweek period. Although the subject size was limited and there was no control group, this study gives athletes a potentially beneficial exercise to be done during their season. This can be utilised when gym equipment access is limited while travelling and can also be performed in the home setting. Although it does not replace a comprehensive rehabilitation program, it has the potential to reduce pain in-season when recovery is limited due to congested fixture schedules. Athletes can utilise this exercise before practices/games if they are feeling increased pain and it could lead to an increase in performance.

“This paper reviews the use of the Spanish squat isometric exercise and its effects on patellar pain in athletes. The intervention demonstrates a cost-effective and safe way to maintain strength while reducing pain in-season for athletes of various sports. Clinicians can prescribe this exercise to patients who have a restricted ability to attend therapy due to schedule constraints from travel.

“During the season when athletes are dealing with ongoing knee issues, this exercise can be a valuable tool to reduce pain. This may allow the athlete to return to sport earlier, along with helping them manage the injury throughout the season.”

Comparing rest intervals in upper body strengthening exercises

OBJECTIVE

In strength training, varied rest intervals have been studied to determine the effects on strength gains in upper body training. This study compared a fixed rest interval of 75 seconds to self-selected rest intervals between sets of upper body strengthening exercises.

The purpose of the study was to determine whether either rest interval produced greater strength changes in a population of young men who were trained in resistance training.

WHAT THEY DID

Thirty-three men between ages 21-22 were split into two groups - self-selected rest intervals and a fixed rest interval of 75 seconds. The exercises performed included chest press, lat pull-down, shoulder press and seated row

The subjects completed three sets with 75% of one repetition maximum until repetition failure of each exercise three times a week for eight weeks. Following each session, the subjects were given 16g of protein. Their strength gains along with repetitions performed were compared. The self-selected rest interval was measured for comparison within that group.

WHAT THEY FOUND

The study found there was a significant increase in repetitions performed by the self-selected rest interval group compared to the fixed rest interval group. They found the self-selected rest interval group ranged from 82.4 seconds-146.3 seconds, which resulted in this group taking 37% more time to complete each session when compared to the fixed rest interval group.

Strength gains were not significantly different between groups but did show a small increase in the self-selected rest interval group when compared to the fixed rest interval group.

Practical Takeaways

The study showed that both the fixed rest interval and self selected rest interval groups increased their strength over an eight week upper body strengthening program.

From a volume perspective, a higher self-selected rest interval was more beneficial than a shorter fixed rest interval between sets. Although this is true, the self-selected rest interval generated only minimal strength gains above the fixed rest interval group, which spent less time performing the exercises. There may have been greater gains in strength with the self-selected rest group if the study had been performed over a longer duration than eight weeks.

Based on this study, one can attest that an ideal range of rest intervals is dependent on the goals at hand and time barriers that are present. When using a self selected rest interval, a range of 84-146 seconds was found to have similar strength benefits as a fixed interval of 75 seconds. Picking the proper rest interval for you or your athletes may depend on the goal at hand. In order to maximise repetitions, a self selected rest interval is more beneficial compared to a self selected rest interval. Strength coaches can utilise this information to plan out appropriate training plans for their athletes.

"This paper describes how different rest intervals between sets of upper body exercises affects strength in young male athletes. Giving athletes a proper range of 75-150 seconds of rest between sets can lead to consistency in their training and appropriate strength gains. This study may have shown more positive benefits to a self-selected rest interval if it was studied over a longer period of time.

"Strength coaches can use this information to better plan out training programs and athletes can utilise it in order to understand how long they should be resting between sets for consistent gains in strength."

Is it time to re-think the 7-day microcycle?

OBJECTIVE

With professional sporting competitions looking to eke out as much value from sporting teams as possible by having them play long seasons or twice-weekly matches, the ability to plan microcycles from match to match is more important than ever. One example is the Australian National Rugby League competition (NRL), where 24 regular season matches are played over six months, with 5-10 days between matches.

As always, there is more than one way to skin a cat with some teams preferring to rest matchday (MD) +2 and start training MD +3 while others prefer to start training on MD +2.

Currently, no research has examined the impact of these different microcycle structures on technical match performance and physical load during field sessions. Therefore, this study aimed to identify how different microcycle structures affected on-field physical training load and physical and technical performance during matches.

WHAT THEY DID

Thirty-four professional rugby league athletes (age = 26 ± 4 yr) from the NRL were followed for the 26 week inseason.

For the first half of the season, the first skills session of the week was performed on MD +2 with the main field session on MD -3. This was labelled the early microcycle (Mcearly). For the second half of the season, the first skills session was performed on MD +3, allowing for an extra day of recovery The main field session was performed on MD -2. This was labelled the delay microcycle (MCdelay).

Physical output was measured using Catapult GPS during training and matches. Playerload per minute (PL.min-1), Playerload below 2 m.s-1 per minute (PLslow.min-1), metres per minute (m.min-1), high speed running >4.0 m.s per minute (HSR.min-1), and high-speed running >5.5 m.s per minute (Sprint.min-1) were the variables assessed. For technical statistics, metres gained and frequency of runs with the ball, tackles missed, and tackles made were analysed from match footage.

Practical Takeaways

The 7-day microcycle is a hotly debated topic with many options. I’ll list them below:

Option 1

MD +2 (Easy skills day)

MD +3 (Volume/contact technical session)

MD -3 (Off)

MD -2 (Fast technical session)

MD -1 (Potentiation session)

Option 2

MD +2 (Easy skills day)

MD +3 (Off)

MD -3 (Hard technical session)

MD -2 (Off)

MD -1 (Potentiation session)

Option 3

MD +2 (Off)

MD +3 (Easy technical session)

MD -3 (Hard technical session)

MD -2 (Off)

MD -1 (Potentiation session)

Option 4

MD +2 (Easy technical session)

MD +3 (Volume/contact technical session)

MD -3 (Fast technical session)

MD -2 (Off)

MD -1 (Potentiation session)

Option 5

MD +2 (Off)

MD +3 (Technical Skills)

MD -3 (Off)

MD -2 (Main Fast Session)

MD -1 (Potentiation session)

Overall, it seems removing an extra training day during the in-season from typical microcycle structures allows for better recovery, by improving physical outputs during training without impacting competition performance.

Within collision sports, physical recovery takes much longer than non-contact sports due to the increased muscle damage and therefore, the extra day may be warranted.

If using MD +2 as a training session, this is best used as an easy gym session (bodybuilding/prehab style) with technical light skills such as individual and team skills based on the previous match. For example, if a team struggled with defending a particular attacking shape, the session can be dedicated to fixing this issue before going full speed or contact the following day

WHAT THEY FOUND

All physical measures during the first skills session increased in MCdelay compared to MCearly. Physical output was maintained during the main field session on MD -2 even with the increased physical output in the previous day’s skills session.

No difference in technical match performance was seen between microcycle structures.

Interestingly, HSR.min-1 increased while PLslow.min-1 decreased in matches during MCdelay compared to MCearly

“Delaying the start of a microcycle raises the question of what you do with the extra day off. It could be a knee-jerk reaction to have to do something such as bringing the players into the facility for ‘recovery’ and wellness. I think complete rest at home is a better option so they can spend time away

“However, that doesn’t mean it has to be mental rest. An interesting idea would be using virtual reality to go through game scenarios so they can do mental reps without the physical toll. While this technology hasn’t made its way into rugby (mainly within American football), sending players video to analyse at home is another option to keep them sharp and learning.”

Technology & Monitoring

This month ’ s top research on technology and monitoring.

IS THE 1080 SPRINT DEVICE RELIABLE FOR SPRINT ASSESSMENTS?

VALID OPTIONS TO MONITOR INTERNAL TRAINING LOAD IN FEMALE SOCCER PLAYERS

Is the 1080 Sprint device reliable for sprint assessments?

OBJECTIVE

Through radar technology, coaches are able to examine the force-velocity (F-v) relationship as an athlete accelerates in a valid and reliable way (see HERE).

Likewise, the 1080 Sprint is a device that involves a cable connected to a computerised motor, allowing for both resistance, towing, and assessment during locomotion activities. The cable is attached to the athlete via a belt, and provides data based on velocity and distance as the device unravels.

Although constrained research (see has suggested HERE) acceptable accuracy and testing of experienced sprinters (see ) has been performed, there is uncertainty HERE around the device s ability to provide a valid and reliable measure. It is important for coaches to understand and trust the measurement methods, analysis, and results when using the 1080 Sprint to assess acceleration and sprint qualities.

Therefore, this study sought to identify the amount of variation and fluctuation when measuring horizontal F-v profiles using a 1080 Sprint compared to previously validated radar technology during a 30-m sprint test.

WHAT THEY DID

Twenty high-school American football players (16.5±0.51 yr) from the same training group, who were not lineman, had two 30-m sprints measured using a radar device and a 1080 Sprint simultaneously The second attempt was the trial analysed, with the first used as backup if needed. The starting position was a standing, staggered stance, with consistent placement of the radar (5-m behind start line and 1-m high, targeting the athlete’s centre of mass) and 1080 Sprint device (1.5-m behind the start line, set to isotonic mode, and the minimal 1-kg load set for resistance).

Velocity-time data was analysed for each athlete to create a F-v profile using a validated calculation method created by Morin et al. For each athlete and device, time constant tau and horizontal maximal velocity were identified, then theoretical maximum velocity, theoretical maximum horizontal force, peak power, and slope of the F-v profile were calculated. These calculations were compared between measurement devices to identify the average measurement difference (bias), random error, and limits of agreement (see HERE).

Practical Takeaways

It is best to not compare metrics obtained from two different types of technologies (e.g. motorised cable and radar technology).

When using two different devices to measure something because of access, facility, travel, etc., the bias and random error are often too much to overcome. For example, even if bias was minimal (1 arbitrary unit) between two devices, a random error of ±7% between devices creates a wide range of disparity that makes comparison too unpredictable to compare.

Objective measures are preferable when measuring performances (e.g. timing sprints, assessing jumps, or measuring velocities).

Look to technologies that provide accurate (valid) and consistent (reliable) metrics for improved confidence (e.g. laser or radar timing gates, force plates, video technology, or linear position transducers). These devices typically allow for a better identification of change (improvement or decrement) as well, due to their higher sensitivity or sample rates. They are more costly than a stopwatch or measuring tape, but worth the investment, if possible.

If financial constraints do not allow for purchase of robust technologies, using some smart phone applications (see ) have HERE shown to be valid and reliable in measuring speed, power, strength, velocity, and even change of direction ability These modes can serve as an option for smaller groups with more time to analyse information.

In order to accurately calculate a F-v profile, it is important that initial movement is identified correctly (see ) for a sprint. Given this HERE limitation, it may be best to constrain the movement to a loaded jump or lift (e.g. leg press) that allows measurement of one movement with maximal intent from a stationary position. This could be done with a range of at least five light to heavy loads, and help coaches identify a slope through linear regression that would identify theoretical maximal force and theoretical maximal velocity capabilities. Which in turn would guide training based on results (e.g. if force capacity is low, focusing on getting stronger; or if velocity capacity is limited, focus on elasticity and speed (i.e. sprinting and jumping).

WHAT THEY FOUND

The 1080 Sprint returned higher measurements for tau (measure of time from initial movement), horizontal maximal velocity, and that yielded a higher theoretical maximum velocity as well.

§ However, all 1080 Sprint measures were within 6.32% of the radar device.

Random error between the two devices was largest for slope of the F-v profile (±12.3%) and tau (±9.98%).

Initial movement acceleration data from the 1080 Sprint appeared inconsistent, as five athletes had unlikely elevated values for velocity, suggesting that the centre of mass, true stationary movement, or slack in the cable cause data to not be captured correctly

“The results of this research encourage coaches to compare ‘apples to apples’ when looking at data metrics. In that when collecting performance data, it is best to not interchange results from two different types of technologies. Doing this impacts the reliability of the measures, confusing coaches and athletes with which result and equipment to trust.

“Coaches should be selective in what and how they measure performance - they should identify ways that provide results which are both reliable and repeatable. Often times, trying to simplify athletes’ actions by constraining things as much as possible (e.g. keeping hands on hips for a countermovement jump), or being consistent with measurement methods and equipment set-up (e.g. staggered stance exactly 1-m before the ‘starting line’, with radar or laser technology set to 1-m high) will provide results that coaches can share with confidence.

“In regard to the 1080 Sprint, it appears to be a training tool that provides resistance or assistance with sprinting, offering excellent opportunities around training. But as an assessment tool, it is not going to be the ‘gold standard’ or provide results with the consistency offered through laser or radar devices. However, if coaches can keep set up and execution consistent, the results can be compared, but only to those provided by the 1080 Sprint (i.e. ‘apples to apples’).”

Valid options to monitor internal training load in female soccer players

OBJECTIVE

Session rating of perceived exertion (sRPE) is a validated measure that uses an athlete s subjective report of intensity (see ), multiplied by the duration of a HERE session, to estimate internal training load of an athlete. It is time-efficient and zero-to-low cost for teams to implement when looking to better quantify and manage training volume and intensity

In addition, the ability to track an athlete’s heart rate during training has further strengthened the reliability of sRPE (see ) through comparison of training impulse HERE (TRIMP), which is a calculation based on heart rate and session duration (see ). Heart rate (HR) monitors can HERE also be used to measure peak HR (HRpeak) and quantify intensity based on a percentage of HRpeak (%HRpeak), because time spent at near maximal intensities is important for proper aerobic development and preparation for match-play (see HERE). However, this applicability of sRPE has yet to be validated in female soccer players. Therefore, this study attempted to identify a relationship between sRPE and TRIMP in female soccer athletes’ training, specifically examining the ability for players to recognise different ranges of %HRpeak through RPE during a session, as well as the variation between players and training sessions for the duration of time >90% of Hrpeak.

WHAT THEY DID

Seventeen female soccer players (age 21.4±2.1) in the first division of the Portuguese championship league had a total of 18 training sessions examined across a six-week period during their competitive season.

The structure (e.g. warm-up, activation, technical training, and small-sided games) and workload of each session was consistent. HR data was collected to assess relative HR and TRIMP values, and RPE was recorded following each session.

Prior to the research window, participants were familiarised with HR monitors and RPE scale, and had their HRpeak assessed by performing a Yo-Yo Intermittent Recovery Test Level 1. Data from each athlete was compared between sessions, looking for relationships between TRIMP and sRPE, RPE and %HRpeak, as well as examining variability between players for RPE, sRPE, TRIMP, %HRpeak, and time spent >90%HRpeak.

Practical Takeaways

If you are going to implement the use of RPEscale as a measure of internal training load, it is critical that you use a validated scale, being definitive and consistent in how you explain the units (e.g. RPE of 10 is maximal effort, RPE of 7 is a steady jog that could be maintained for >30min, RPE of 5 is a brisk walking effort, etc.). This way athletes understand the number that represents their activity and coaches have reliable data across their team (see HERE).

Coaches should not wait until the in-season period to begin implementing monitoring. Allow for 4-6 weeks of familiarisation with any sort of monitoring tool (e.g. RPE, HR monitor, etc) before expecting to have time-efficient and consistent information that will be useful. It will take time for the athletes to get comfortable with establishing a routine and adopting use into their routine.

Be consistent when collecting RPE data (see HERE):

§ Data should be collected 15-30-min after the session has ended.

§ The question should be simple and consistent (e.g. How hard was practice today?)

§ Keep your reaction neutral, do not respond negatively or make the athlete feel guilty about their response.

§ An athlete s report should not be heard by other athletes, because that information could influence their response as well.

Athletes can learn to better understand, and in

Want

turn report, submaximal intensities if given the opportunity to have a live look at their heart rate during activity. Coaches can set athletes up on a bike or treadmill with a HR monitor so they simultaneously feel and see what submaximal intensities (e.g. 60-80% HRpeak) feel like. This helps them understand the variations between walking and maximum effort to have a better sense when reporting RPE values.

When it comes to defining the question of RPE, coaches have the ability to identify the quality they’re most interested in tracking (e.g. breathlessness, leg muscle exertion, technical/cognitive exertion, see ) to better capture the HERE load of activity and manage data that is meaningful to the athlete s performance (e.g. cardiovascular fitness, speed, power, strength, alertness).

Coaches should perform assessments at the beginning and end of the off-season period to capture performance ability, identify potential limitations, and/or showcase the impact of training (e.g. improvement or decline). The assessments should be carefully selected to represent physical qualities that are important to on-field success. In this study, the Yo-Yo Intermittent Recovery Test Level 1 is a test that simulates the erratic on-field activity and allows athletes to showcase maximal capacities.

Some workouts during the week need to promote time spent >90% HRpeak, as this high level of intensity is beneficial to improving aerobic fitness, but only necessary in small doses (roughly 6-8% of total volume, or about 7-min total, see HERE). Coaches can utilise HR monitors to confidently measure if athletes are achieving sufficient time at this intensity, ensuring adequate development and avoiding under-preparing athletes for the demands of competition.

The pairing of both HR and RPE is helpful to increase the confidence of each variable. Coaches should not be overly focused with one specific monitoring metric, but rather confirm expectations and identify outliers (e.g. a low HR but high report of RPE, or a training session that was meant to be lowintensive but registered elevated HR). An objective measure of HR is valuable, as it brings accountability to the athlete s efforts and their subjective RPE report.

WHAT THEY FOUND

TRIMP and sRPE proved to be consistent with one another (‘large’ correlation coefficient (r=0.78), suggesting a strong relationship, but not perfect). However, serving as valid representations of internal load.

RPE values were reported in coordination with relative HR values (e.g. higher RPE values were noted during higher %HRpeak intensities).

There was a wide range of variability in time spent >90% HRpeak between players and even in the same player between sessions.

On average, players spent about seven minutes (roughly 8 percent) of the training session at HR >90%HRpeak.able cause data to not be captured correctly

“I think monitoring an athlete s HR during training and collecting RPE are both great options to better understand and manage the internal training load of an athlete.

“The monitoring process should aim to provide as much of a holistic representation of training load imposed and the athlete’s psychophysiological response, as possible. The combination of these two variables provides both an objective measure (HR) that brings about accountability and accuracy of a physiologically-dominant metric, paired with a psychologically-dominant account of how the athlete is feeling systemically based on myriad factors (e.g. sleep, nutrition, hydration, previous training, outside stressors, etc.). The pairing provides an excellent representation for coaches to have a quantified representation of an athlete’s psycho-physiological state, providing confidence in workload and guidance for subsequent sessions prior to competition.

“The important thing to remember with training is that it is seemingly easy to stay healthy by avoiding volume and intensity, but do not fall victim to the trap of always ‘doing less. The goal of training is to expose athletes to a stimulus that creates an adaptive response. A sufficient stimulus that promotes physiological changes and improved performance, adequately preparing them for the demands of a competition and competitive season.”

Fatigue & Recovery

This month ’ s top research on fatigue and recovery

DO COMPRESSION GARMENTS BOO RECOVERY IN RUGBY PLAYERS?

HOW SHOULD NEUROMUSCULAR F BE ASSESSED FOR ATHLETES?

Do compression garments boost recovery in rugby players?

OBJECTIVE

Compression garments are used to improve venous blood flow from the lower body and upper body back up to the heart. Compression in the lower extremity, which was looked at in this study, is highest at the ankle and decreases in a proximal direction toward the thigh. Proposed benefits in an athletic setting include an improvement in exercise-induced muscle damage, decreases in soreness and improved performance.

This study looked at elite rugby players and compared the effects of the use of custom compression garments compared to standard-sized garments. Both sets of compression garments were also compared to ultrasound treatment to the lower extremity as the control group. This was used as the sham or placebo treatment of the study

The main goal was to evaluate the effect of varying levels of compression pressure on muscle recovery following exercise.

WHAT THEY DID

The current study evaluated the effects of compression with varying pressures to the lower body. Comparison included medical grade-compression (20-35mm Hg) with standard-sized compression (8-15mm Hg) or no compression.

Baseline measurements of isometric knee extension strength, subjective soreness levels, midthigh girth (swelling), Plasma Creatine Kinase levels (muscle damage), countermovement jump performance and sprint speed were taken. The athletes were then tested via an Eccentric Muscle Damage Protocol which included 20 sets of 20 metre sprints followed by 100 drop jumps. Following testing, the athletes in compression groups wore their garments after exercise for 48 hours (sham treatment group received five minutes of sham ultrasound to the lower extremity).

Subjects were assessed at 24 and 48 hours immediately after exercise for all baseline measurements.

WHAT THEY FOUND

When comparing custom garments to standard-sized garments, compression stayed higher and more consistent with custom made garments. From baseline to 24 and 48 hours following, strength levels and sprint performance decreased in all groups. However, strength levels and sprint performance were higher when comparing custom compression to standard-sized garments or no compression. Along with this, midthigh girth and Creatine Kinase levels were less in the custom compression group.

Soreness levels were decreased with custom compression garments but not at a significant level when compared to standard-sized garments or no compression

Practical Takeaways

This study shows the use of compression garments can be a useful tool in recovery. Higher levels of compression in the lower extremity may aid in minimising the loss of speed and strength over multiple days following athletic activity Along with this, there is evidence for improvement in soreness levels and muscle damage with use of compression garments at higher pressures.

From this study we can see that compression garments can enhance overall recovery from exercise-induced muscle damage. When comparing medically graded compression to commercially available compression, there is a clear benefit to higher levels of pressure. This assists to improve venous return from the lower extremity back to the heart. With this, blood flow is improved along with reducing lymph fluid which may cause swelling.

Specifically looked at in this study was rugby players. Due to a congested fixture and practice schedule in the season, full recovery is never a guarantee. Compression garments can help players improve their recovery on rest days in order to have the best performance possible.

“This study shows the positive effects of compression on athletic performance. Overall, it aids with blood flowing smoothly back and forth between the lower extremity muscles and the heart. With this, higher grades of compression at levels up to 35mmHg from ankle to thigh have been shown to be the most effective. Athletes should receive a prescription from their physician or consult with them prior to purchase from a medical supply store.

“In a season where recovery is hard to come by on a consistent basis, compression garments can ameliorate the effects of exercise-induced muscle damage while assisting with maintaining performance.”

How should neuromuscular fatigue be assessed for athletes?

OBJECTIVE

Neuromuscular fatigue can be defined as the reduction in maximal voluntary force that a muscle can generate due to repeated or sustained muscular contraction. In team sports it is essential to monitor this due to the inherent risk of injury that develops as fatigue accumulates.

This article presents the information available regarding the effect of neuromuscular fatigue along with the tools available to measure and monitor it throughout an athlete’s season.

WHAT THEY DID

Management of fatigue is imperative for controlling how an athlete adapts to training, ensuring they are ready for competition and are at a lower risk for developing injury or illness. Neuromuscular fatigue is measured via the following tools:

Athlete self-report measures: Psychobiological state, which is affected by prolonged periods of demanding cognitive and physical activity, can affect the perception of fatigue. This can decrease an athlete's perceived exercise capacity The RPE scale (Rating of Perceived Exertion) has been found to be a reliable and short measure of an athlete's level of physical stress experienced.

Biochemical markers: Testosterone and cortisol levels can be used to evaluate the responses to different workloads. Testosterone, which is an anabolic hormone, allows for muscle hypertrophy and glycogen synthesis which is needed for strength gains. Cortisol is a stress hormone indicating the endocrine’s response to exercise.

Surface electromyography: The collective electric signal from the muscles controlled by the nervous system producing a muscular contraction/movement.

Sprinting ability and vertical jump tests: Measures athletes’ speed, time to recover, jump height and peak force.

Practical Takeaways

The study explains what neuromuscular fatigue is and how it can affect athletes throughout the season through a cumulative effect of altered recovery Along with this, the study goes into detail on ways to monitor neuromuscular fatigue in high performance settings.

The most effective ways to monitor fatigue include sprinting and vertical jump testing. Specifically, the Countermovement Jump has been found to be the most effective test which can be monitored throughout a season to monitor fatigue. A decrease in jump height along with force output can be a marker for neuromuscular fatigue. This can be monitored via force platforms, contact maps, phone apps and accelerometers.

This information can be utilised to monitor the athlete’s fatigue throughout the season and allow for identification of those athletes not responding to the training program. With this, prevention strategies can be put into place earlier on to avoid injury

WHAT THEY FOUND

It was found that sprinting ability and vertical jump tests were the most widely used and effective way of measuring neuromuscular fatigue. Monitoring an athlete’s acceleration, along with their ability to maintain a maximal speed for a given time, is the best way to measure their fatigue while sprinting.

When it comes to vertical jump testing, it is a practical measure with a high degree of adoption in high performance sport settings. It allows for measurement of jump height and peak force with different tools which can be repeated by practitioners throughout the season. The most commonly used vertical jump test is the Countermovement Jump which can be correlated to a number of different sports including basketball, American football and soccer

"All athletes will encounter levels of neuromuscular fatigue throughout their seasons, which will increase as it progresses.

Effectively monitoring these levels can be beneficial to reduce risk of injury and identify those athletes who require additional intervention in their training programs.

"Vertical jump and sprint testing have been found to be the best measurement tools in order to monitor fatigue effectively This can be done through the use of force platforms along with phone apps. For coaches who do not have that readily available, subjective reporting of fatigue and objective sprint times and vertical jump heights can be monitored."

Youth Development

This month ’ s top research on youth development.

HOW FAMILIES AND PHYSICAL EDUC

CAN IMPACT KIDS’ SCREEN TIME, BOD INDEX AND ATTITUDE TOWARDS SPOR

CAN NEUROMUSCULAR TRAINING HELP IMPROVE PERFORMANCE IN YOUTH TENNIS?

How families and physical education classes can impact kids’ screen time, body mass index and attitude towards sport

OBJECTIVE

Children are the building blocks of a better future. Empowering children to engage in a healthy lifestyle will hopefully embed good habits into their week, and therefore, inspire the future generations to also lead a healthy and active lifestyle.

Children s physical health is therefore of importance, with many countries considering this with strategic importance for economic growth Despite this, surveys (HERE). collected on children and adolescents (2-19yrs) found that obesity rates were rising by 6.9% for males and 6.4% for females in developed countries In addition, as (HERE). children spend a majority of their time at home, the influence of family must not be overlooked. Therefore, the aim of this study was to explore the influence that family had on an individual s attitude to sport, participation in sport, time on a screen, and body mass index (BMI).

WHAT THEY DID

A cross-sectional study was used to evaluate the influence that a family’s attitude to sport had on their participation, screen time and BMI. In total, 589 valid questionnaires were collected from children in China, with an equal split of male and female participants. The main instrument for collecting this information was a questionnaire consisting of three main parts. These were: Personal Background – where the following variables were collected: gender, age, height, and weight.

Children’s sport participation – In this section, the researchers were concerned with exercise participation, calculated using the following formula: exercise participation = exercise frequency x (average exercise intensity + exercise duration). A higher value was correlated with greater exercise participation per week. In addition, this section sought to gather information on screen activities in a week. Participants assigned a number which correlated with a time in minutes into the survey (e.g. 1 = 30 mins or less, 2 = 31-60 mins, 3 = 61-90 mins, 4 = 91-120 mins, and 5 = 121 mins or more).

Home environment – this part includes the basic information about the children s caregivers, including their occupation, education level, physical activity levels, and attitudes towards sport on a likert scale (e.g. “disapprove, not very agree, general, somewhat agree, and strongly agree”) on a 1-5 system.

Once collected, an independent sample t-test and onefactor ANOVA were used to analyse the measured variables.

Practical Takeaways

Given the role of physical education on health and wellbeing, ensuring that PE is an enriching process is important. In the attached podcast, guest Mark Collard discusses the importance of “connection before content” which I personally believe is key to supporting the physical education curriculum. Mark states the best programmes in the world, delivered poorly, are average at best.

Developing a relationship built on mutual respect is a recurring theme that consistently comes up in literature surrounding good teacher-student relationships (HERE) and health outcomes. As S&C coaches/PE teachers, we often come from a biassed position of loving sport. This clearly isn’t the case for all children, so here is my guide on how to bridge this with those who do not yet love physical education:

1. What do we want to see from our curriculum? In a typical PE session, I want to explore some of the common movement ailments we see in children. Typically, these are weak hip flexors, hamstrings, overhead range of motion, and limited thoracic mobility As soon as children get into a lesson, small tag-based games are a great way to (HERE) get the muscles warm and ready for physical activity Following this, a good warm-up consisting of inchworms (HERE), (HERE), Spiderman stretches overhead lunges (HERE) (HERE) and bodyweight squats set a good tone for the lesson whilst challenging poor posture/muscular imbalance..

2. At this stage of the lesson, pupils have moved well and raised their heart rates. This is a small ‘tick’ in my head, as

we’ve already made some progress in the lesson. Having achieved this, splitting large groups into smaller groups is important to meet the needs of individuals more adequately This can be done by understanding the students’ ability, or understanding their complex individual needs (e.g. wellbeing vs. performance). In this attached poster, knowing your athletes well can help to form these groups. Splitting the group down now allows me to progress onto the next part of the lesson, typically a skill (e.g. throwing) which must be broken down and placed into a fun drill (e.g. how many catches can we make in 20 seconds). Here, engagement looks like focus, compliance, and high levels of differentiation to support the varied abilities in the lesson. Varying this task by incorporating a bounce, greater distance, or single-hand catching is a necessity to stretch the child’s development.

3. Finally, we must place several constraints on this skill, developed to test this within a more competitive setting. For example, an overarm throw is only useful if a student knows the context (i.e. when and how to use it at the right time). Practically speaking, you wouldn’t use this method of throw if you were close to your team mate, so providing opportunities to practise this is essential. This can take time, so you must be patient. The most important part here is that you get creative. Some excellent examples can be seen in the attached video, where scarfs, larger balls and competition have made some very basic exercises a lot more fun. Avoiding static practice (e.g. throwing a ball at a wall) should be avoided, as this can be tedious. Better variations may include some form of throwing rounders, handball, or frisbee football.

WHAT THEY FOUND

This study found there are significant differences in children s family sports attitude, screen time and BMI in the presence of different family structures and/or education levels.

In addition, family sports attitude is significantly correlated with parents’ education levels and children’s sports participation levels. Moreover, lower levels of education correlated with higher levels of screen time and BMI.

Children’s sports participation and screen time play a mediating role between family sports attitude and screen time. Therefore, family sports attitude does impact a child’s physical health and BMI. Family structures defined as the level of support/interaction between parents and the child were similar for high to low contact time with family, suggesting that these findings can be applied universally

“This study highlights the vital role that ‘environment’ has on developing patterns of behaviour that are conducive to developing a love and curiosity for physical activity Just like reading and maths, when a child learns about keeping themselves physically and mentally well, this must be supported from home to unlock further knowledge and development within this area. Although challenging, engaging parents within this process is vital to reduce high levels of BMI and screen time. This starts within schools, which must find ways to deliver physical education that is both engaging, fun, and supportive of a ‘work-hard’ culture. Some of the strategies used in the attached article are a fantastic way to then bridge this with parents from home. Setting homework, family challenges, and opportunities to explore family health habits may bridge this. This demonstrates the importance of buy-in from parents when looking to develop physical activity

“Future studies may wish to look at the impact of such interventions (e.g. parent-student homework) on physical activity levels and change over time. A longitudinal study would be advised to ensure that this is not a short-term change.”

Can Neuromuscular Training help improve performance in youth tennis?

OBJECTIVE

Tennis is a high-intensity sport - an average point requires players to cover between 8-15m, complete four change of direction (COD) movements, and contact a ball 4-5 times At a high level, these movements are (HERE). performed at incredibly high velocities, with an equal emphasis placed on accuracy and tactical awareness.

As such, high levels of technical competency in footwork, speed and mental agility/perseverance are important. To develop these qualities, neuromuscular training (NMT) (e.g. sprint and multidirectional movements) have been previously identified as an effective means of developing tennis performance (HERE).

However, few studies have examined the combination of NMT and regular training completed together Therefore, the purpose of this study was to compare the impact of NMT and regular tennis training on performance.

Thirty-two participants (7 yrs) were randomly assigned to either a training (n=16), or control group (n=16). All participants attended tennis training twice a week for eight weeks. The control group received regular tennis sessions, whilst the training group received additional NMT for the whole eight-week period.

The NMT consisted of sprint and COD work with a coach lasting roughly 15-20 minutes. Pre-test were collected for 30m sprint times, 3x10m shuttle run test, 5-10-5 COD test, and a spider agility test Post scores were (HERE). collected to assess the training effect of regular vs. regular + NMT training on several performance variables.

Practical Takeaways

When working with children of this age (<7 yrs), effective NMT shouldn’t necessarily look like typical strength training (e.g. squats and deadlifts). This isn’t to say these skills cannot be developed, but the emphasis should be on mastery of the key fundamental movement skills in a fun and safe environment. Activities that involve balancing, balloons, quick feet and lots of energy are a great way to instil a love of learning and physical activity An excellent example of some warm-up activities can be seen Delivering these in a fun and HERE. playful manner is not only a preference of youth as stated in the attached podcast, but also develops associations and links between training patterns and performance.

When working with children, thinking about what you want to see and then reverse-engineering this into some form of game or activity is a fantastic way to build up a skill tool kit. For example, past experiences of movements, or similar movements, allow a young child to visit that skill with more precision on the next encounter as highlighted in the attached article. Practically speaking, if coaches wanted to develop lateral transitions, they may perform activities that look like this. However, other alternatives may be crab tag (e.g. a small area where the taggers can only move laterally), mirroring a player who is shuffling, or ship to shore variations Small refinements on technique (HERE). over time will lead to adaptations, but remember, too much information can get in the way of good movement and fun.

As well as placing some NMT into regular training, injury prevention is another important consideration when working with youth players. In a study by Oosterhoff et al., (2018), common injuries occurred when training exceeded six hours a week, no warm-up was undertaken, or there was evidence of previous injury in the same area (e.g. a previous hamstring injury was indicative of a future hamstring injury). Given these recommendations, coaches need to find creative and fun ways to incorporate injury preventatives in the warm-up. For example, ankle stability could be achieved by getting players to tip-toe around cones and balance on one leg when a gesture was made (e.g. whistle, cone, music stops). Within this, a good needs analysis that covers both the sport and the athlete (see tennis example should reveal any issues HERE) that require attention from the coach which can be focussed on. Finally, and although difficult, coaches should try to stick to the six-hour a week rule with their players. I would suggest four hours is a good target, as this allows youth to pick up a donor sport to support diverse learning experiences through a well-structured tennis LTAD programme (HERE).

From this study, no significant differences were found in the pre-test scores. However, significant improvements were seen in the training group compared to the control group.

More specifically, these improvements were observed in the 30m sprint times, 3x10m shuttle runs, and COD ability (e.g. 5-0-5 test and spider agility test scores).

NMT combined with regular tennis training led to improvements in sprint and COD ability in children when compared to regular tennis training alone.

“NMT combined with regular tennis training was more beneficial than tennis training performed alone. This is really important, as children are at sensitive periods of development around age seven In view of this, coaches should look (HERE).

to combine regular NMT sessions in their training programmes, such as those attached in the video. An underlying feature which may explain this phenomenon is that coordination training improves intermuscular coordination, synchronisation of body-segments and an improved physical ability (e.g. eccentric strength) to maintain good COD positions.

“Studies like this one go a long way in supporting young performers who are attending clubs to improve their tennis skills. An important factor to consider is that when working with young children, learning must occur in a fun and safe environment. To echo this point, parents must understand that tasks do not necessarily need to look specific to transfer An individual tapping a balloon up as they move is developing hand-eye coordination, spatial awareness with their head-up, and effective footwork to negotiate other performers. All of these are similar skills that a player will need to return an effective backhand from a poor original position (e.g. on the other side of the court). To develop this, coaches may look to prompt parents to take part, explain the process behind such training, and stay strong to their routine, supported by testing (again, remember the context) to support performance enhancement.

“In summary, we do want children to improve their tennis skills. However, there are many more skills (e.g. teamwork, social intelligence and fundamental movement skills) that can and should be developed when working with youth.”

Nutrition

This month ’ s top research on nutrition

CAFFEINE AND TAURINE: A SYNERGISTIC EFFECT ON ANAEROBIC PERFORMANCE?

DOES INTAKE OF CARBOHYDRATE GELS DURING LONG-DURATION EXERCISE FURTHER IMPROVE PERFORMANCE

RED SPINACH EXTRACT: COULD THIS NEW NITRATE SUPPLEMENT BENEFIT RESISTANCE-TRAINED ATHLETES?

Caffeine and taurine: A synergistic effect on anaerobic performance?

OBJECTIVE

Caffeine is a stimulant that has well-established benefits for athletic performance during aerobic exercise. However, recent findings suggest caffeine ingestion might also enhance anaerobic performance. Caffeine improves exercise performance primarily via antagonism of adenosine receptors in the central nervous system, leading to increased neurotransmitter release, motor firing, and pain suppression.

Taurine is a sulphur-containing amino acid found in animal proteins. Taurine has been proposed to improve athletic performance by modulating fat metabolism, reducing inflammation, and expressing antioxidant effects. However, research of taurine in humans is limited, so further research is required to establish these proposed effects and the underlying mechanisms.

Due to these proposed different mechanisms, combining these supplements could have synergistic effects on exercise performance. Caffeine and taurine are often combined in energy drinks. However, the dose of caffeine contained in energy drinks is often below the recommended dose (3-6 mg.kg-1) necessary to produce any performance enhancing effects. However, coingestion of higher doses of caffeine and taurine have shown positive effects on peak and mean power output during a Wingate Anaerobic test in male athletes. However, research on female athletes is limited.

Furthermore, there is limited research on the effects of caffeine supplementation in high habitual caffeine users on anaerobic performance.

This study investigated the effects of combined ingestion of caffeine and taurine on Wingate Anaerobic test performance in high habitual caffeine female athletes.

WHAT THEY DID

Seventeen female team sport athletes participated in this randomised, double-blind, crossover study All participants were classified as moderate to high habitual caffeine users (340.1 ± 28.6 mg.day-1).

Participants completed four identical experimental trials under the different supplements: caffeine and taurine combined (caffeine: 6 mg.kg-1; taurine: 1g), caffeine alone (6 mg.kg-1), taurine alone (1g), or a placebo (300 mg maltodextrin). Supplements were ingested 60 minutes before a 30-second Wingate Anaerobic test. Participants completed a five-minute warm-up at 60 watts for each Wingate test with five-second sprints without resistance at the second and third minutes before cycling at maximum effort for 30 seconds from a stationary start against a fixed load of 7.5% of body mass. Each test was separated by a wash out period of 48 hours.

Performance markers of peak power, mean power and fatigue index were measured throughout the test. Heart rate and capillary lactate were measured before and immediately after the test. Ratings of perceived exertion were measured immediately following the test.

WHAT THEY FOUND

Peak power following supplementation of caffeine and taurine combined was significantly higher than placebo (+31.9 watts) and taurine alone (+28.8 watts). However, no differences in peak power were observed between supplementation of caffeine and taurine combined with caffeine alone.

Mean power following supplementation of caffeine and taurine combined was significantly higher than placebo (+9.7 watts). However, no differences in mean power were observed between supplementation of caffeine and taurine combined with caffeine or taurine alone.

Fatigue index was not found to be different between any condition.

There were no differences in heart rate, capillary lactate, or ratings of perceived exertion between any condition.

Practical Takeaways

Supplementation of caffeine and taurine combined could improve power output during short bursts of high intensity cycling in high habitual caffeine female athletes.

However, practitioners should avoid recommending the use of a caffeine and taurine combined supplement based on the results of this study, since this is the first study to assess the effects of a caffeine and taurine combined supplement on anaerobic performance.

Although peak power following supplementation of caffeine and taurine was greater than taurine alone, it was not greater than caffeine alone. This could suggest that caffeine played a greater role in performance improvements than taurine in the combined supplement.

However, the 1g dose of taurine used in this study may be considered a ‘low dose compared to amounts used in previous research. A study on male team sport athletes showed positive effects of a greater acute dose of taurine (50mg.kg-1) on Wingate anaerobic performance, compared to placebo, caffeine, or caffeine and taurine combined. Thus, future research should compare the effects of a higher taurine dose on anaerobic performance in female athletes.

Previous studies have suggested that anaerobic performance increases following acute caffeine ingestion in male and female athletes. However, the results of this study do not support these findings. Reasons for these differences may be due to the high habitual intake of caffeine in participants of the following study. High habitual intakes of caffeine have been shown to blunt or reduce the ergogenic effects of caffeine intake. In contrast, other studies have shown that high habitual intakes of caffeine do not reduce athletes’ response to caffeine supplementation on exercise performance. Practitioners should thus shift their focus from advising athletes to limit their caffeine intake to educating them on the potential risks of high caffeine intakes on recovery (e.g. consuming caffeine late in the day can reduce sleep quality and impair subsequent recovery and performance).

“While previous research supports taurine’s use in improving athletic performance, the study designs, subject population, and experimental outcomes are too variable to fully support taurine s efficacy as an ergogenic aid.

“Research appears to support taurine’s role in improving aerobic exercise performance to a greater degree than anaerobic performance, yet its effects remain unclear. Pre-workout drinks containing taurine are largely popular in resistance trained populations, who report these drinks can increase anaerobic performance (e.g. increase in strength and power). While these drinks may have some performance enhancing effect, caffeine is likely the primary driver of this.

“Further, these drinks often contain stimulants that are banned under the WADA prohibited list, so they should be avoided to minimise doping risk.”

Does intake of carbohydrate gels during long-duration exercise further improve performance

OBJECTIVE

Carbohydrate intake during exercise can delay the onset of fatigue and improve performance of prolonged endurance exercise. It is recommended that athletes consume 30-60g of carbohydrate per hour for exercise lasting longer than one hour. However, recent studies have suggested that during prolonged exercise bouts (>2.5 hours), athletes would further benefit from the ingestion of multiple carbohydrate sources. This has been shown to increase the maximal rate of exogenous carbohydrate oxidation up to ~1.5g.min-1 (90g per hour) compared to the ingestion of a single carbohydrate source.

Energy gels are a convenient form of carbohydrates to consume during endurance exercise where movement can restrict an athlete s ability to consume carbohydrates from solid foods. Despite review papers suggesting that performance benefits are not affected by the form (solid, liquid, or gel) of carbohydrate ingested during exercise, limited studies have assessed the performance outcomes resulting from the ingestion of gel-based carbohydrate supplements.

Furthermore, athletes could benefit from more precise recommendations for periodising carbohydrates from energy gels during exercise beyond the current recommendations (i.e. will consuming one dose of 60g of carbohydrates improve performance greater than two doses of 30g of carbohydrates?). However, limited doseresponse studies on carbohydrate ingestion during exercise have been published.

This study investigated the effects of different carbohydrate energy gel ingestion schedules during two hours of steady-state cycling exercise on blood glucose, blood lactate, and performance of a subsequent 15minute time trial.

WHAT THEY DID

Ten trained cyclists (five male and five female) participated in this randomised, counterbalanced study Participants completed an initial graded cycling test to volitional exhaustion to determine VO2max. Participants then conducted three exercise trials. Each trial consisted of a 15-min rest, followed by two hours of cycling at 70% of VO2max, followed by a 15-min maximum distance fixed gear time trial. Each trial was separated by four to seven days.

Blood lactate, blood glucose, respiratory exchange ratio (RER) and ratings of perceived exertion (RPE) were measured every 30 min during the two-hour cycling phase of each trial. Blood lactate and blood glucose were also measured immediately after completion of the time trial.

Participants were instructed to consume an energy gel 15-min prior to the two hours’ cycling stage of each trial. Each energy gel contained 100 calories, 25g carbohydrates from fructose and maltodextrins, electrolytes, amino acids and Vitamins E and C. Energy gels were then ingested at different time points during the two hours’ cycling stage of each trial: one trial at a 30min ingestion interval from the initial gel intake (T1; at 15-, 45-, and 75-min during exercise), one trial at a 45-min ingestion interval after the onset of exercise (T2; at 45 and 90 min during exercise), and one trial with no gel ingested during exercise (T3).

Practical Takeaways

Ingestion of energy gels during prolonged cycling elevates/maintains blood glucose levels and improves subsequent performance in male and female athletes. More frequent ingestion of carbohydrates could elicit additional performance benefits for exercise longer than two hours.

Although no reports of gastric distress were observed in this study, previous research has reported that 10-20% of runners experience serious gastrointestinal distress following more frequent consumption of carbohydrate gels. Practitioners should work with athletes to develop individualised feeding strategies to eliminate the possibility of gastric distress during prolonged exercise bouts. For example, athletes may benefit from consuming carbohydrates from solid foods during the early stages of the event and progress to liquid or gel forms of carbohydrate as exercise intensity increases.

The carbohydrate gel used in this study combines fructose and maltodextrin as sources of carbohydrates. This is based on the findings of previous studies, which suggest a combination of carbohydrate sources such as fructose and maltodextrin or glucose and fructose can increase carbohydrate oxidation compared to the consumption of a single carbohydrate source during

WHAT THEY FOUND

Blood lactate increased over time in each condition and was greatest in T1. Blood lactate was significantly greater in the T1 at 120 min (4.98 mmol.L-1) and at the end of the time trial (7.8mmol.L-1) than baseline (3.01mmol.L-1). No significant differences between conditions were observed.

Blood glucose decreased over time in each condition. However, ingestion of the carbohydrate gels in T1 and T2 appeared to increase or at least alleviate drops in blood glucose before the end of the 120-min cycle, compared to T3: Blood glucose level at 60 min during exercise was significantly greater in T2 (127.6 mg.dl-1) than T3 (102.8 mg.dl-1).

RPE increased over time in each condition. In T3, RPE was significantly greater at 60- (13.1), 90- (14.1) and 120 min (14.7) than at 30 min (12.1). In T1 and T2, RPE was significantly greater at 90- (T1: 12.8; T2: 13.3) and 120 min (T1: 13.2; T2: 13.7) than at 30 min (T1: 11.7; T2: 12.3). RPE was significantly greater in T3 than T1 at 90- (T3: 14.1; T1: 12.8) and 120-min (T3: 14.7; T1: 13.25) during exercise.

RER decreased over time in each condition. RER in the T1 condition remained higher than in T2 and T3 at every time point. However, in T1, RER was significantly lower at 60- (0.90), 90- (0.88) and 120 min (0.87) than at 30 min (0.92). No significant differences between conditions were observed.

Distance covered during the time trials was significantly greater during T1 (7.56 km) and T2 (7.16 km) than during T3 (6.69 km), with moderate effect sizes between trials.

prolonged exercise bouts (>2.5 hours). Here, athletes should aim to consume up to ~1.5g.min-1 (90g per hour). However, when exercise duration is shorter, multiple transportable carbohydrates may not have the same performance benefits, and athletes could benefit from intakes of ~1g.min-1 (60g per hour).

Participants in this study were instructed to consume fluids ad libitum, meaning that hydration status was not controlled.

Athletes must balance their carbohydrate intake with fluid to prevent dehydration since solid foods and highly concentrated carbohydrate solutions have been shown to reduce fluid absorption. These strategies should be tried and tested in training before events or competitions.

Carbohydrate gels and liquids are supplements. If using these, athletes must ensure that the products are informed sport certified to minimise the risk of a doping ban.

“The benefits of carbohydrate ingestion during exercise are prolific, so athletes should consider their use in endurance events if they are serious about improving performance. However, consuming carbohydrates during exercise can be challenging and requires some planning. There is a fine balance between ingesting optimal amounts of carbohydrates to improve performance whilst avoiding gastrointestinal discomfort, such as bloating or feeling sick, which could have the opposite effect. Therefore, practicing fueling strategies during training is essential to determine the right type, timing, and total of carbohydrates you need to consume during competition.

“Further, any nutritional strategy during long duration exercise and competition should be equally paired with an optimal fueling strategy for before and after competition.”

Red spinach extract: Could this new nitrate supplement benefit resistance-trained athletes?

OBJECTIVE

Dietary nitrate is a popular supplement among endurance athletes. Dietary nitrate is converted to nitric oxide in the body, which has been shown to have an ergogenic effect on prolonged submaximal exercise and high-intensity, intermittent, short-duration efforts. The proposed mechanisms explaining these benefits include the dilation of blood vessels to increase blood flow in the delivery of oxygen to the working muscle, increased efficiency of mitochondrial respiration and an enhanced function of type II muscle fibres.

Nitrates are found in high concentrations in leafy green and root vegetables, such as spinach, rocket salad, celery, and beetroot. Most research has focused on the performance-enhancing effects of beetroot juice as a supplement rich in nitrates. More recently, alternate supplements rich in nitrates such as red spinach extract have been studied. Red spinach extract has been shown to improve 4-km cycling time trial performance and ventilatory threshold during a graded cycling test.

While research has focused primarily on endurance exercise, emerging evidence has suggested a positive effect of nitrate supplementation on resistance exercise performance. However, no studies have examined the effects of red spinach extract on acute resistance exercise performance.

This study investigated the effects of seven days of red spinach extract supplementation on bench press performance, muscle oxygenation, and cognitive performance in resistance-trained males.

WHAT THEY DID

Ten resistance-trained males participated in this randomised, cross-over, placebo-controlled, doubleblind study. Before supplementation, participants were familiarised with laboratory equipment and completed baseline tests to determine maximum strength (bench press one-rep max).

Participants were randomised to receive either a red spinach extract supplement (500mg x4 per day; 180mg nitrates) or a placebo (500mg maltodextrin x4 per day) for seven days. After the loading phase, participants were given an additional dose on two consecutive days of testing: Participants completed a cognitive Stroop test (to assess cognitive function) and a visual analogue scale task before supplementation. Participants rested for 30 minutes before completing a second Stroop test, warmup protocol on a cycle ergometer and a second visual analogue scale task.

One hour post-supplementation, participants completed five sets to failure at 75% of their one-rep max on the bench press, with each set separated by two minutes of rest. Muscle oxygen saturation at the shoulder, peak power, and mean power were recorded.

Finally, participants completed a final visual analogue scale task and Stroop test, while researchers measured their heart rate and blood pressure.

Questionnaires were provided at baseline, 30 minutes post-ingestion, and immediately after completion of the bench press exercise, which measured the participant’s subjective feelings of focus, energy and fatigue using a visual analogue scale.

At the end of each experimental trial, participants were asked to provide a rating of perceived exertion. A washout period 14-days separated experimental trials of the two conditions.

Practical Takeaways

Supplementation of red spinach extract containing 180mg nitrates per day for seven days followed by a single acute dose prior to exercise is unlikely to enhance resistance exercise performance.

These results are similar to findings from a previous study that administered a larger dose of 985mg nitrates per day for six days and found no improvement in countermovement jump performance, isometric strength, and muscular endurance compared to placebo. However, conflicting results from previous research have shown that nitrate supplementation at higher acute doses ( 400mg) before exercise from beetroot juice improves total weight lifted, repetitions to failure and mean power output of a bench press exercise protocol, and peak isometric force of mid-thigh pulls.

Although results remain equivocal, it is possible the dosage administered in this study was too low to observe an ergogenic benefit for resistance exercise. Additionally, as beetroot juice seems to provide more consistent improvements in resistance exercise performance, a study comparing equal higher doses of beetroot juice, red spinach extract and other forms of dietary nitrates would help determine whether beetroot juice has unique benefits.

Due to the inconsistency in results between studies, practitioners should avoid recommending nitrate supplements to resistance-trained athletes. Furthermore, only males were included in this study, so results cannot be generalised to female populations. Future research should investigate the effects of higher acute and chronic doses of nitrates from red spinach extract in male and female populations. Additionally, studies have shown that performance gains from nitrate supplementation may be reduced in highly trained athletes, so research should consider both untrained and resistance-trained populations.

WHAT THEY FOUND

There were no significant differences in total bench press repetitions, peak power, mean power, muscle oxygen saturation, heart rate, systolic blood pressure, rate of perceived exertion, Stroop test scores or subjective feelings of focus, energy, fatigue and muscle pump between the red spinach extract and placebo conditions.

While resistance-trained individuals may not benefit from the nitrates in vegetables such as beetroot or spinach, they contain a variety of nutrients that would contribute to daily micronutrient requirements and the athlete s overall health goals, such as improved immunity Where athletes participate in endurance exercise, these foods may be of greater benefit. However, to reach the level of nitrates necessary to enhance performance, athletes would need to consume large quantities of these foods that could lead to adverse gastrointestinal symptoms. Athletes should test before training to determine their preferred source of dietary nitrates before competition.

“While the literature consistently shows that dietary nitrates are successful at improving exercise performance during short-term, highintensity endurance exercise, there lacks confounding research for practitioners to recommend the use of nitrate supplements to resistance-trained athletes.

“Most current research has reported benefits of supplementing with beetroot juice as a source of nitrates. These are widely available in ‘shots’ that can be taken quickly before training. In my experience, these are well tolerated by most athletes. Until the literature on alternative nitrate supplements develops, beetroot juice is a safe option for use before short-duration, highintensity endurance exercise.

“Still, I would not recommend using beetroot juice to directly improve resistance exercise performance. Money could be better spent on buying the vegetables themselves to maintain health and immunity or on other supplements such as creatine monohydrate that have been shown consistently to improve resistance training performance.”