How do peripheral fatigue and central fatigue differ?

Peripheral fatigue and central fatigue represent two distinct phenomena that influence athletic performance, particularly in endurance activities such as running.

Peripheral fatigue occurs at the muscle level. It involves the depletion of energy sources, such as glycogen, and the accumulation of metabolic byproducts like lactic acid, which can impair muscle contraction. This type of fatigue is directly related to the physical capacity of the muscles to perform work. When exercising intensely, the muscle fibers may lose their ability to generate force effectively, leading to sensations of fatigue in the muscles themselves.

On the other hand, central fatigue pertains to the brain and the central nervous system's role in initiating and sustaining muscle contractions. It can result from a variety of factors, including psychological state, motivation, and the overall perception of exertion. When central fatigue sets in, it can diminish the signals sent from the brain to the muscles, leading to decreased performance even if the muscles themselves are not yet fully fatigued.

Thus, the distinction emphasizes that peripheral fatigue arises from the physical and biochemical processes within the muscles, while central fatigue is linked to neurological and psychological factors. This understanding is crucial for coaches and athletes, as addressing both types of fatigue can lead to better training and recovery strategies.