Which type of fatigue is directly related to decreased voluntary efforts during exercise?

Central fatigue is characterized by a reduction in the neural drive or voluntary efforts of the central nervous system to activate the muscles during exercise. This type of fatigue occurs when the brain and spinal cord are unable to produce the required motor output, leading to decreased muscle activation and performance. Central fatigue often results from extended periods of high-intensity exercise, causing mental fatigue, depletion of neurotransmitters, or changes in motor unit recruitment patterns.

It’s important to understand that while peripheral fatigue involves mechanisms at the muscle level, such as energy depletion and accumulation of lactate, it does not directly affect the brain's ability to send signals to the muscles. On the other hand, central fatigue influences how motivated or capable an individual feels to continue exercising, which directly decreases voluntary efforts.