marathon runners

Depletion of energy reserves


“The wall does not exist,” says coach and former athlete Bruno Heubi. Long web pages, however, try to explain it and each marathoner hears about it as soon as he enters the race. “The wall, as we understand it, only concerns elite marathon runners who will finish the race in less than three hours. Because of their very high speed, they consume a large amount of glycogen, until suddenly being without fuel, “explains the coach.

Glycogen, the store of sugars/carbs in the liver and muscles, is a rapidly available source of energy. Thus, the higher the speed, the more the runner will use these reserves until exhausting them. “It must then switch to another source of energy: fats. These are less effective and available in providing immediate energy, “explains coach Heubi. In the absence of sufficient carbs, the runner is then forced to reduce his speed, and in some instances, is no longer able to advance. According to coach Heubi, those who run the marathon in more than four hours will not use as much glycogen as elite runners. What some people call “wall” is actually a mixture of several factors forcing them to slow down.

According to former athlete and coach, Jean-Pierre Monciaux, the effects of the wall are amplified by muscle fatigue after several hours of racing. “Because of this exhaustion, microtrauma caused by the stride, and lack of energy reserves, the brain makes a circuit breaker to preserve the body,” he explains.

It is often said that this difficulty in advancing arrives at the 30th kilometer, but this extreme fatigue can very well happen before or after, depending on the level of training but also how we manage the race. For example, a marathon runner who goes far too fast will quickly deplete carbohydrates and find himself without energy in a short time. “It can even happen after an hour and a half if we have not prepared well or if we have gone too fast,” says coach Monciaux.

Focus on nutrition and hydration


To cross the wall of the marathon without difficulty, you must also rely on a complex carbohydrate diet, which will build the glycogen stores needed on the race day.

“Those who will rely on the pasta party the day before to have the necessary energy are wrong. We start to build our body carb stores at least  five days before race day and not the day before,” said sports nutritionist Christophe Parguel. If the race is held on Sunday, start eating starchy foods such as rice, pasta, quinoa at every meal on Wednesday.

Hydration is also essential to limit muscle fatigue and pass the finish line in relatively fresh condition. Whether during the training phase or a few days before the race, the marathoner must consume between 2.5 and 3 liters of water per day. Then during the race, he will stop at each refueling. “I recommend drinking between 500 ml and 1 liter of water per hour, but 95% of runners are satisfied with just one cup,” says coach Heubi.

Respect your race strategy


Euphoria and stress overwhelm the runner at the time of departure, expected and feared for several months. Driven by these emotions and the speed of others, the marathoner leaves faster than expected. Some people think that by winning a few minutes at the start of the race, they can afford to walk towards the end. This is a bad calculation, because often it is because we run too fast at the beginning that we walk after. “They will use a lot of sugars at the beginning and end up with no fuel at the end,” explains coach Heubi. And, according to coach Jean-Pierre Monciaux, during the first hour of the race you have to be in economy mode, and “run in a relaxed way, respecting your pace, and focus on your stride”. Follow these common sense tips, and everything should be run smoothly.