Nutrition needs to match the demands of training. When energy intake is not sufficient to meet the body’s needs, the impact can appear not only during exercise, but also during recovery and in the ability to maintain a consistent training routine.
For endurance athletes, this can be even more important, as long training sessions significantly increase energy and carbohydrate requirements.
Less Energy, Less Capacity to Train
Carbohydrates are one of the main sources of energy for higher-intensity exercise and also contribute to the replenishment of muscle glycogen stores.
When carbohydrate intake is insufficient, glycogen stores may not be fully restored between training sessions. In practice, this can make it harder to maintain pace, increase perceived exertion, and reduce training quality.
The Impact Goes Beyond Exercise
Consistently eating too little can also interfere with important recovery processes. The body needs energy and nutrients to repair tissues, replenish energy stores, and support physiological functions.
When there is a persistent gap between the energy the body expends and the energy it receives from food, athletes may experience greater fatigue, poorer recovery, and difficulty sustaining their training load.
A Practical Example
Imagine a runner who completes a 90-minute workout on Tuesday and another intense session on Thursday. After the first workout, they have a small meal and consume very little carbohydrate for the rest of the day.
By Thursday, even after resting, they may arrive at the workout without having adequately restored their glycogen stores. As a result, maintaining the planned pace may feel harder, perceived exertion may be higher, and performance may decline.
In this case, the problem is not necessarily Thursday’s workout itself, but the fact that recovery between the two training sessions was not supported by nutrition that matched the demands of the training.
Eating More Does Not Mean Eating Without a Strategy
The goal is not simply to increase the amount of food consumed. Nutrition should be adjusted according to training volume and intensity, with particular attention to energy demands, carbohydrate availability, and adequate protein intake.
On more demanding training days, for example, carbohydrate requirements tend to be higher. During recovery periods, the nutritional strategy may be different.
Performance Also Depends on Energy Availability
Adequate nutrition is not only about providing energy for the next workout. It ensures that the body has the resources it needs to recover and respond to training stimuli.
That is why, when performance starts to decline, it is worth looking beyond the training itself. Training more is not always the solution. Sometimes, what is missing is enough energy to sustain what you are already training for.
