How to improve your performance through diet?


Running is a sport that requires a lot of energy and discipline all year round. The training quality and competition performances depend not only on the personal investment into the sport, but also on the diet that should be part of any runner's training plan

Energy intakes should cater for the needs.

The diet should cover the running energy expenditure that depends on various criteria: duration, speed, weather conditions, runner's weight, running surface...

During training, the workload varies from one person to another, however most experienced runners train several times a week and certain times of the year include one race per week. An appropriate quantity of energy intake is then required to ensure performance. Excessive calorie intake makes you gain weight, which can have a negative effect on training and an insufficient intake leads to a drop in performance and an increased risk of injury.

Energy needs vary based on several criteria: intensity, frequency, duration, speed, weather conditions, runner's weight, running surface... They may change as the season goes on. Thus, the needs may be high when you run at slow speed, but for a prolonged period of time. Similarly, in periods of inactivity or when injured, runners must adapt their energy intake based on their energy expenditure.

A balanced diet and performance

A well balanced diet guarantees intake of all the nutrients that your body needs. Food balance is built on a daily basis to achieve performance improvement. Excess intake of a nutrient comes at the expense of others. Conversely, nutrient deficiencies cannot be corrected instantly. Of course, a small occasional deviation is acceptable without major consequences. A balanced diet has a direct impact on training. It helps support the intensive training load while limiting the risk of illness and injury. A balanced diet offers numerous advantages for runners; it helps to:

  • optimise training,
  • improve recovery from training and competitions,
  • maintain a steady weight,
  • reduce the risks of injury and illness,
  • guarantee good race preparation,
  • achieve good performances.

In order to guarantee a balanced diet, you must eat:

  • starchy foods with each meal to replenish your energy,
  • meat or fish or eggs, once or twice a day,
  • at least five portions of fruits and vegetables a day to provide vitamins, fibre and water,
  • three dairy products a day to provide proteins and calcium,
  • a limited amount of fatty food to provide lipids and vitamins,
  • a limited amount of sugary food to please your taste buds,.
  • as much water as you want

Hydration and performance

 Hydration plays an important role in performance; you need to drink before, during and after training sessions - and even more so in hot weather. The intake of water and / or isotonic drinks avoids dehydration that could result in fatigue and injuries. Don't forget that dehydration is a runner's worst enemy.

Using an isotonic drink such as ISO or ISO+ will help meet both the hydration and carbohydrate needs during training. Remember that compensating for the energy loss will allow the runner to maintain his/her level of performance throughout the session. 


Recovery after a training session is already preparation for the next session. Replenishing your water, sugar and electrolyte reserves, which are considerably reduced by training, is essential for a successful performance. This phase begins as soon as the training session is over. The objective is to take in water, carbohydrates, electrolytes and proteins as quickly as possible.

To do so, several options: After drink is convenient as it provides everything in the right proportions. Another option is ISO combined with two after sport bars...

Marie Fauchille
Dietician | Nutritionist
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      Do you know about isotonic drinks? When you're exercising, it's essential to take in fluids in order to maintain your performance level. But after an hour of exercise, water is not enough! Your muscles need an energy boost from an intake of carbohydrates and sodium, to compensate for sweating. These two essential elements are exactly what isotonic drinks supply the body with during sporting activity!


      The recovery stage is crucial for progress and physical performance. Indeed, if your recovery is poor, the body cannot regenerate.