What effect does muscle fatigue have on performance during exercise?

Muscle fatigue significantly impairs muscle contraction efficiency during exercise. When muscles are subjected to prolonged activity, various biochemical changes occur, including the depletion of energy stores, the accumulation of metabolic byproducts like lactic acid, and alterations in electrolyte balance. These changes can lead to a decrease in the muscles' ability to generate force, reducing overall performance.

As fatigue sets in, the nervous system may also become less effective at stimulating muscle fibers, further hindering contraction efficiency. This diminished ability to contract results in a reduction in strength, endurance, and overall athletic performance, making this option the most accurate representation of the effects of muscle fatigue during exercise.