What happens to performance when a substrate is exhausted?

When a substrate, such as glycogen or fatty acids, is exhausted, the body’s ability to produce energy during physical activity is significantly impaired. This depletion leads to fatigue and a decrease in overall performance. Glycogen, in particular, is a primary energy source for high-intensity exercise. Once glycogen stores are depleted, the body struggles to maintain optimal energy levels, resulting in reduced endurance and an inability to sustain the same intensity of exercise.

As energy levels drop, athletes may experience symptoms like decreased strength, slower reaction times, and an overall lack of motivation or ability to push through strenuous activities. Thus, performance is adversely impacted when critical energy substrates are exhausted, making it essential for athletes and fitness enthusiasts to manage their nutrient intake properly to sustain energy levels during training and competition.