Football carb periodisation - Dr Tom Little & Mark Hearris

feature

Pictured: Arsenal’s Theo Walcott (right) and team-mates during a September training session at London Colney.

FOOTBALL AND CARB PERIODISATION FEATURE/DR TOM LITTLE & MARK HEARRIS Nutrition is a field that is awash with contradictory information. In particular, carbohydrates or carbs present a dichotomy of interests. For years carbs have been associated with improved exercise performance and athletes have intuitively consumed high carb diets to support performance.

H

owever, in recent years, there has been a resurgence of interest amongst social media users in the use of low carb and/or high fat (LCHF) diets as the optimal fuel for athletes.

Additionally, the marketing prominence of protein and cultural support of low carb dieting has led to some athletes actively avoiding traditional carb choices. However, in contrast to both dietary extremes, it appears athletes should ‘meet somewhere in the middle’ and switch between periods of high, moderate and low carb intake, whereby carb intake is periodised in accordance with the goal of the session, the individual athlete and the weekly training schedule (Anderson, 2017),

8

Carbs are seen as the prominent fuel for intermittent exercise as they are capable of producing energy at a faster rate than fat or protein. Although the oxidation of fat provides a higher energy yield than carbohydrate, its rate of energy production is certainly insufficient for high intensity actions that are frequently performed in intermittent sports like football. Indeed, key moments in football are typically made up of high intensity actions, such as sprints, shooting and jumping, with matches typically containing 150-250 such actions. In accordance, numerous studies have shown that starting a match with high muscle glycogen stores, via a high carb diet, is beneficial to football

performance as it allows players to cover greater distances and more of this distance to be covered at higher intensities (Saltin, 1973), whilst maintaining technical performance. Therefore, there appears to be an overwhelming case for footballers consuming a diet rich in carbs.

Somewhat paradoxically, however, an emerging body of evidence suggests that restricting carbs at selected times surrounding training can augment the aerobic training effect (Bartlett, 2015) via increased mitochondrial production, resulting in a greater capacity to produce energy aerobically, utilise fat for energy production and spare precious muscle glycogen for high-intensity actions. As the

football medic & scientist aerobic system is the predominant energy source during match play, and muscle glycogen is essential for performance, it could be argued that it may be beneficial for a footballer to periodically consume low amounts of carbs surrounding training.

Practically, low carb availability can be achieved using a variety of strategies: (1) chronic low carb intake, (2) an acute period of low carb intake (e.g. low carb intake in the evening, then train in the morning before breakfast or following a protein only breakfast), (3) two training sessions with minimal carb intake in-between.

However, such severe restrictions of carbs are probably inadvisable to footballers during the in-season as they are required to compete so regularly and have to frequently perform high-intensity, and skill based actions in training. In addition, low carb availability is associated with compromised immune function, increased muscle breakdown, whilst chronic reductions in carbs decreases our capacity to use carbs as fuel (Cox et al, 2010). As such, severe low carb strategies may only be suitable during the off-season, with injured players performing low-to-moderate intensity exercise or with players who excessive body fat has been identified as a severely limiting factor to performance.

Whilst severely restricting carbs may not be a viable option for footballers, reducing carbs at appropriate times may be beneficial for optimal health and body composition.

Figure 1. Benefits of high and low carb intakes for footballers High carb foods such as pasta, cereals, breads and high sugar foods tend to have a low ‘nutritional value’, whereas colourful vegetables and salad contain less carbs but have greater health benefits (in terms of vitamins, minerals and fibre). Furthermore, many traditional high carb foods, such as white bread, pasta and potatoes, also have a high glycaemic index, which indicates how quickly a food elevates blood glucose.

A rapid rise in blood glucose causes a high insulin response, resulting in a rapid uptake of nutrients and, as such, high glycaemic foods are good for promoting carb storage

(A) Traditional British 2-match week

(B) European style 2-match week

(C) 3-match week with Tuesday fixture

(D) 3-match week with a Wednesday fixture

Figure 1. Relative match & training loads for weekly structures commonly used in football.

MD refers to number of days since (+), and leading up (-) a match. Red = high carb, Yellow = moderate carb, Blue = low carb.

following exertive exercise. However, habitual intake of high glycaemic foods can cause body composition issues due to increased fat storage and a lack of satiety, and potential health issues such as insulin resistance and type II diabetes. Additionally, high carb foods, particularly those containing sugar, tend to contain a higher number of calories for a given quantity of food than less carb-dense foods, hence their regular consumption can be associated with weight gain unless energy expenditure is consistently high. Finally, varying carb intake may help promote ‘metabolic flexibility’ where the body is primed to use both carbs and fats optimally, as and when required.

In light of the above, it appears that players should vary carb intake based upon match, and training demands. Increasing carb intake around matches and hard training will maximise performance, whilst reducing carbs when physical demands are lower, allows the promotion of foods that optimise health and lean body composition, which will further increase performance potential. Footballer’s energy demands and performance tasks tend to vary during the week based on match schedules and the manger’s training philosophies. Match performance is paramount, and matches normally represent the highest energy demands during the week. Therefore, carb intake should be high the day before, and on the day of a match. When there is no midweek fixture, teams tend to perform mid-week high load training session(s), with the aim of improving, or maintaining fitness levels. High load training days also need to be supported by high carb intakes to optimise performance and recovery, and minimise injury risk. Teams tend to use low to moderate training loads ~ 48hrs before a match, in order to reduce fatigue and maximise fuel stores, and 48hrs post-match to promote recovery and reduce injury risk.

These low load periods (barring the day prior to a match) present an opportunity to reduce carb intake. Figure 1 illustrates relative loading for weekly structures commonly used in professional football.

The red bars indicate days were carb

9

Situation

Carb guidelines

Comments

2-3 g.kg of athletes BM per day

~ ;^f V[hRPT\XR index & high fibre vegetables

Daily needs for fuelling & recovery: Fat loss & injury rehab

Aim of the athlete is to reduce fat mass or regain fitness before returning to play

~ 8]R^a_^aPcT _TaX^Sb of fasted training Light training

Low intensity & skill based sessions

3-5 g.kg per day

~ ;^f \^STaPcT glycaemic index depending on preference

Moderate

High intensity / double sessions

5-6 g.kg per day

~ 7XVW V[hRPT\XR [^f fibre) index foods are advisable between double sessions

intakes need to be high to support match performance or hard training. Yellow bars suggest moderate intake of carbs, when training load is moderate, or training load is low but there is a short period between matches. The blue bars indicate days where training load is low, and therefore carb intake can be low. Table 2 illustrates recommended carb quantities for these different training and match scenarios, and Table 3 shows an example meal plan with varying carb intakes.

Practical Implications ~

Acute fuelling strategies: Carbohydrate loading

Preparation for match

6-8 g.kg per day

~ 7XVW V[hRPT\XR [^f fibre) index foods allows gut comfort and lower match day weight

Immediate refuelling

Optimise muscle glycogen resynthesis post-match

1-1.2 g.kg per hour for 3-4 hours

~ 27> ST]bT b]PRZb and drinks are advisable – combine with protein if targets cannot be achieved

Table 2. Practical carb guidelines for the athlete

10

~

Footballers should align their carb intake with the energy, and performance demands of competition and training. Increasing carb intake around matches and hard training will maximise performance, whilst reducing carb intake around on days off, and low training loads, allows the promotion of foods that promote health, such as vegetables, and lean body composition, such as proteins.

To provide a balanced input of carbs, whilst promoting health, footballers should eat mainly low glycaemic carbs, such as vegetables, salads, oats, beans, nuts and seeds. Around matches, players should allow some inclusion of higher glycaemic carbs to provide an easily digestible efficient energy source.

football medic & scientist

Pictured: Charlton Athletic players warm up before their game against Gillingham in September.

~

~

During the off-season or if a player is injured, in may be advantageous to train during periods of low carb availability to induce greater aerobic adaptation and fat oxidation. However, training should only have moderate intensity and performance demands, and adequate protein (1.5-2g.kg day) should be ensured to prevent muscle wastage.

Training in the morning before any carb intake probably represents the most viable methodology of low carb training for footballers, rather than prolonged carb restrictions.

Players need education tools which align food to performance, health and

body composition goals. They then need practical cooking skills to reap the benefits of their more informed choices.

References Anderson, L., Orme, P., Naughton, R. J., Close, G. L., Milsom, J., Rydings, D., O’Boyle, A., Di Michele, R., Louis, J., Hambley, C., Speakman, J. R., Morgans, R., Drust, B. & Morton, J. P. (2017). Energy intake and expenditure of professional soccer players of the English Premier League: Evidence of carbohydrate periodisation. International Journal of Sport Nutrition & Exercise Metabolism, 4, 1 – 25.

Bartlett, J. D., Hawley, J. A. & Morton, J. P.

(2015). Carbohydrate availability and exercise training adaptation: Too much of a good thing? European Journal of Sport Science, 15, 3 – 12.

Cox, G. R., Clark, S. A., Cox, A. J., Halson, S. L., Hargreaves, M., Hawley, J. A., Jeacocke, N., Snow, R. J., Yeo, W. K. & Burke, L. M. (2010). Daily training with high carbohydrate availability increases exogenous carbohydrate oxidation during endurance cycling. Journal of Applied Physiology, 109, 126 – 134.

Saltin, B. (1973). Metabolic fundamentals in exercise. Medicine & Science in Sports, 5, 137 – 146.

BIOS Dr Tom Little is a Performance Specialist with over 17 years experience in professional football.

Tom developed Colour-Fit™, an app that simplifies choosing and preparing optimal meals for performance, health and body shape goals.

For more info visit www.colour-fit.com or email tom.little@sky.com Mark Hearris is a PhD researcher within the sports nutrition & exercise metabolism research group at LJMU. Mark also provides nutrition consultancy support to Preston North End Football Club.

Table 3. Meal plan for a 2-match British training structure taken from Colour-Fit™. All the pictures link to Meal Cards, Prep Videos and nutritional breakdowns.

11