12 minute read
Preventing Dropout in the Ultramarathon
According to conservative estimates, there has been a growth of over 500% worldwide in the number of runners attempting an ultramarathon from 2013 to 2017. For most of these first-time runners, reaching the finish line within the time-limit is their primary objective and the priority of the coach is to best prepare the runner for the unique physical challenges of running in excess of 43 kilometres.
This article will examine the stressors that runners most commonly face while attempting the ultramarathon and what strategies the coach can employ in training and on race day to assist their runners to avoid, minimise or manage them.
Common Stressors of the Ultramarathon
Runner feedback reports from the SG Ultra 2017 and Vermont 100 ultramarathons provide us with useful quantitative data on the most common stressors encountered by runners.
Gastro-intestinal problems were the most widely reported challenge from entrants in both events, most commonly described as feelings of nausea, vomiting and difficulty eating or drinking. We will have a look at proposed mechanisms of these symptoms and the coaching practices that can help prevent them in greater detail later in this article.
For the coach, it is interesting to note that most of these issues can be avoided, reduced or managed through adequate specialised preparation. It is therefore unsurprising that runners who worked with a qualified coach for at least three months in the build up to the event had a significantly higher finish rate than those who trained independently or only used a generic training program.
The other interesting point to take from this data is that the self-reported challenges facing ultra-marathon runners appear to be incredibly similar between the events and that the coach can prioritise training methods that help their runners to prepare and cope with the most common challenges. While it is important to acknowledge some variation will exist between races due to distances, elevation, terrain and climate (note the increased reporting of heat issues in the humid Singaporean conditions), general preparation strategies can be recommended for preparing your runner for any condition.
Stressors Associated with Dropout
Not all of the challenges reported from the SG Ultra Marathon and Vermont 100 are going to result in runners dropping out from a race. Understanding the challenges that are most strongly correlated with drop out is useful for the coach who may wish to priortise preparing their runners for these factors.
We have some limited data from Hoffman & Fogard (2011) comparing the reported issues of finishers and non-finishers from the 2009 Western States Endurance Run and Vermont 100 Endurance Race. The data suggests two important factors that coaches should consider.
i) Blisters, muscle pain and exhaustion were significantly higher in finishers than non-finishers, suggesting that these factors are unlikely to be the sole cause of a runner dropping out from a race.
ii) The only individual factor significantly higher in nonfinishers than finishers was the presence of an existing injury. This was further supported by 17 out of 26 non-starters reporting the presence of an existing injury being the cause of their withdrawal from the race, reinforcing the importance to the coach of injury prevention.
Self-Reported Reasons for Dropping Out
Hoffman & Foggard surveyed non-finishers from theultramarathon events, questioning them about the primary factor that caused runners to drop out from the event. The three most common factors were:
• Nausea / Vomiting: 23% of those surveyed
• Difficulty with Cut-off Times: 19% of those surveyed
• Exisiting Injury: 8% of those surveyed
What this information does not tell us is why 23% of runners dropped out after experiencing nausea, whereas 40% of the runners who did finish the race also experienced nausea without dropping out. Were the symptoms more severe or were the runners less prepared to deal with the symptoms when they presented? Was the perceived difficulty meeting the cut-off times due to poor physical preparedness or poor race strategy? How can these results determine our coaching strategy?
The Interaction Between Stressors
What the studies cited in this article did not examine was how the combination of factors work together to influence drop out rates.Anecdotally, while a runner may not drop out from a race if their only difficulty is a few blisters on their feet, if combined with gastrointestinal distress and mild dehydration, it would be more likely that a runner would decide to pull out.
While there is no evidence to directly support this hypothesis in ultramarathon races, we do see a significant effect of the interaction of challenges on an athlete’s likelihood of finishing other ultra-endurance events such as ironman and triathlons(Gublin & Gaffney, 1999; Baker, Cote & Deakin, 2006; Pfeifferet al., 2010). The priority for the coach should therefore be to look at the full range of common stressors that runners are likely to encounter during an ultramarathon and develop a strategy that aims to minimise all of their effects.
The combination of factors may explain why pre-existing injuries are so strongly correlated with higher levels of dropout. Runners may feel capable of completing the race when only dealing with a mild ongoing injury that they have experienced throughout their training, but when combined with other challenges that arise on race-day (e.g. gastro-intestinal distress and exhaustion) the physical distress is exacerbated and the likelihood of dropping out is increased.
Ultimately, it appears that that there is not one individual stressor that is likely to cause a runner to drop out, but the effect of multiple stressors working together. The coach needs to prepare their runner in training for each of the most common stressors and develop raceday strategies that can assist management of symptoms if they occur during the race. The next section of this article will look at how the coach can assist prevention and management of these issues.
Medication Usage in the Ultramarathon
One of the more striking findings from Hoffman and Foggard was the high usage of medication reported during ultramarathon events.
71.3% of all finishers self-reported using medication during the race, with a significantly higher proportion of finishers using medication than non-finishers. Of those who took medication, the vast majority (over 80%) took nonsteroidal anti-inflammatory drugs (NSAIDs), usually for pain relief or to reduce the symptoms of mild tissue injury in the form of aspirin or ibuprofen.
It would be tempting as a coach to see the data and conclude that because there is a correlation between NSAID usage and the likelihood of finishing, that runners should be encouraged to take NSAIDs as a means of reducing pain or discomfort.
However, the authors advise against the use of NSAIDs during ultra-endurance events unless specifically recommended by a medical professional. NSAID usage increases the risk of exercise-induced hyponatremia (see Athletics Coach 1 / 18 for more information) and may restrict vasodilation.
Irritation of the gastrointestinal tract has also been shown to be correlated with NSAID usage (Rainsford, 1999) and may partly explain the high levels of nausea reported among ultra runners.
It is strongly recommended that coaches direct their runners to their primary care physicians prior to a race to discuss NSAID usage, and if recommended by a doctor, to trial usage of medication during a training run.
Training to Avoid Dropout
Establishing a sufficient base of aerobic fitness is obviously essential for tackling any ultramarathon race. However, the correlation between a runner’s weekly training load and their likelihood of a runner finishing the race is not a simple linear relationship where the longer the distance run in training results in a greater likelihood of finishing.
Instead, what we see is that the likelihood of finishing an ultramarathon increases as the runner’s weekly training load increases, but only up to a certain distance. Above that distance, there does not appear to be a significantly improved likelihood of being able to finish a race. Evidence suggests that a maximum weekly training load (prior to the taper period) ~30% greater than the distance of the race will be optimal for preparing runners to reach the finish line, but any additional training is unlikely to increase the likelihood of finishing. While this has been supported by studies examining 50km and 100km races, no research has studied the relationship for longer distance races.
However, it should be noted that weekly training load has been shown to be correlated with faster race times, suggesting that runners who are targeting a specific time or finishing position would most likely benefit from a maximum weekly training load greater than 150km for a 100km race. This is why understanding the objectives of your runners is important prior the design of an effective training program.
Gastrointestinal Issues
Prevalence: Gastrointestinal issues are the most widely reported stressor facing ultra-endurance runners and the limited data that exists suggests that it is a significantly greater issue for ultramarathon runners than in the marathon (Rehrer et al., 1992; Baska et al., 1990). The prevalence of symptoms experienced appears to increase in association with increases in the distance of the event, with approximately 37% of participants reporting symptoms of nausea in a 67km event and 55% of participants reporting nausea in a 161km event (Glace, Murphy & McHugh, 2002). A study by Gill et al. (2015) demonstrated that “nearly all” partcipants from a 24-hour ultra-marathon had blood markers nearly identical to patients admitted to hospital with sepsis. This occurred a result of bacterial endotoxins leaching into the blood during prolonged periods of exercise, triggering the body’s immune response.
Symptoms: Gastrointestinal issues mostly presented with the following symptoms:
• Nausea or vomiting
• Inability to eat or drink
• Diarrhea
Where gastrointestinal distress leads to dehydration, hyponatremia, energy depletion hypoglycemia, symptoms also included:
• Confusion
• Dizziness
• Inability to concentrate
• Loss of consciousness
Causes: The stomach and intestines are muscular organs that require blood flow to able to perform the mechanical and chemical break down of food for digestion. Gastrointestinal distress in ultramarathon runners likely occurs as a result of restricted blood flow to the digestion organs, with the body prioritising blood flow to the skin for the cooling of the body, the delivery of oxygen to working muscles and the transfer of nutrients (Qamar & Read, 1987). This results in a slowing or complete stop of the digestion process and the beginning of symptoms associated with gastric distress. Damage to the gut can also occur in ultra-endurance runners as a result of the prolonged physical disturbance caused by the bouncing of the running motion (Peters & de Vries, 2001).
Prevention / Management
1) “Slow down and cool off”
Ultrarunning expert Jason Koop’s first recommendation for runners who are experiencing a quesy stomach is to slow things up and allow the body to cool down. Pace should be adjusted (to a slow walking pace if necessary) and the body cooled by removing any additional layers or by splashing a small amount of water on a towel or directly to the skin.
This will allow for greater blood flow to be directed to the digestive system, as slowing down reduces the oxygen and nutrient demand from the skeletal muscles and cooling down reduces demand for blood to be sent to the skin for cooling.
Koop advises his first-time ultramarathon runners to drop the pace as soon as symptoms appear as the sooner you can allow sufficient blood flow to return to the digestive system, the sooner the runner will be able to recover.
2) Training History Gill et al. (2015) provided clinical data to demonstrate that training age was positively correlated with higher levels of an anti-inflammatory agent that allowed their gut to better cope with the stress brought on by exercise. It is worth nothing that it was specifically the number of years the runner had been training, rather than the distance or intensity of training that best predicted the runner’s resilience to gastrointestinal issues. The implication for the coach from this finding is that a runner should gradually progress to their first ultramarathon and ideally have at least 18 months of training prior to their first race.
3) Hydration Costa (2014) believes that the maintenance of euhydration should be the runner’s primary priority for preventing gastrointestinal problems in ultra endurance sports. Euhydration should be rehearsed in training so the runner has a good understanding of the amount of fluid that needs to be consumed during the race and their gut is ‘trained’ for intaking the required quantity. The importance of fluid intake was demonstrated in a study by Stuempfle, Hoffman & Hew-Butler (2013), which found that lower fluid intake was associated with GI distress in ultramarathon runners. This was supported by a qualitative observation that fluid intake appeared to be correlated with how runners felt after prolonged cardio exercise, with those who took drinks more regularly feeling better than those who drank infrequently or insufficient volume. Conversely, coaches need to be aware of the risks of overhydration, with very high levels of fluid intake during an ultramarathon correlated with confusion and dizziness (Glace, Murphy & McHugh, 2002).
Key Hydration Considerations
• Sodium supplmentation assists the runner to maintain their body weight throughout exercise, but there is no evidence that it supports a runner’s performance or that a loss of body weight less than 3% has a negative effect on the ultra-endurance runner (Hoffman & Stuempfle, 2014; Hoffman & Stuempfle, 2016; Valentino et al., 2016).
• The risk of over-hydration is highest during the earliest phases of a race and the risks of dehydration increases throughout the race. It has been suggested that a hydration strategy that transitions from “drink when thirsty” to a regulated intake may be effective (Krabak et al., 2017). It may be most effective to calculate the distance it takes for the runner to lose ~2% of body weight using a “drink when thirsty” method and then transition to regulated intake to prevent losing further body weight.
4) Race Day Food Intake Dietician Corinne Peirano has intensively studied nutrition for ultra-endurance runners and offers the following suggestions for prevention of GI distress on race day.
• Food consumed during the race should be composed mainly of half-fast carbohydrates (liquid or half-liquid) and slow carbohydrates (e.g. breads, cereal bars, cookies).
• Consume sugars/fast carboydrates regularly and small meals every 2 to 3 hours depending on digestive capacity.
• Consume 20-50g /hour, including a combination of salty and sweet foods.
• Ensure that food is well chewed, potentially more than a runner is used to. Food particles larger than 2mm may restrict gastric emptying and add stress to the digestive system.
• On the morning of the race, ensure a breakfast high in proteins and carbohydrates is consumed. Corinne recommends including whole-grain toast, eggs, ham or lean meat, a fruit puree and oats or museli.
• Try and time bigger meals with uphill sections where there is less mechanical stress (bouncing around) on the digestive system.
Hotspots / Blisters
Prevalence: Blisters are an almost unavoidable symptom for ultramarathon runners, especially for firsttimers who are yet to develop the callouses and find the personal measures that work for them. However, this is an issue that almost all runners will encounter at some point and the coaching focus should be on management and education.
Symptoms: Pain is the most obvious symptom, usually combined with irritation of the skin, including bruising and blood. What may start as an annoying but relatively harmless irritation can quickly turn into an ongoing pain that completely changes the running gait. This is where blisters are most likely to result in a DNF, where changes to the runner’s natural rhythm result a decrease in pace, stress on different parts of the body, changes to the nutritional plan and adverse psychological impacts.
Causes: The vast majority of blisters on the feet developed during running are friction blisters, caused by the forces generated during footstrike. The occurrence of blisters is increased with additional heat and moisture. Blisters can also be caused by the friction between clothing and the skin, making it important to test out race-day apparel repeatedly in training.
Prevention
1) “Training, Training, Training”: There is strong evidence to demonstrate that repeated exposure to the frictional forces encountered during running improve the body’s ability to prevent blisters from forming. It is important to remember that blisters on the feet are caused by the unique relationship between shoe, sock and foot, making it important to train in the same footwear that the runner intends to wear during the race.
2) Use the Right Equipment: Finding the right pair of shoes and socks should be a runner’s priority from the very start of the training phase. Evidence suggests that friction blisters can be significantly reduced by running with shoes and socks that have been correctly fitted (Knapik et al., 1995). Experimenting with different lacing techniques may also be an effective way to reduce friction blisters - click here for a guide on different methods suited to different feet shapes.
There is some evidence to demonstrate that acrylic fiber socks are more effective than natural cotton fiber socks for preventing blisters (Herring & Richie, 1990), but these socks should be constructed with dense padding to enhance the physical properties of the fibers (Herring & Richie, 1993).
Wrightsock offer a range of prodcuts specifically for ultrarunners using specifcially made acrylic fiber socks - however they tend to trap moisture and become relatively heavy once wet. If you’re running a wetter course or a heavy sweater you might be better off trying a lighter sock. New Balance’s Coolmax socks have also been very well-reviewed and offer a lighter alternative.
When it comes to choosing the right shoe, it will come down to trying on a few different models and finding what feels ‘right’ for the runner. If you are looking for a few models to recommend to your new runners, the following models are generally considered to be among the best models for trail and ultra runners:
Part 2 in the next edition will look at more waysultramarathon coaches are able to assist theirrunners prepare for their first race.
