During intense work, the drop in pH from hydrogen accumulation can lead to:

During intense physical activity, the production of hydrogen ions (H+) increases, which can result in a decrease in muscle pH, leading to a more acidic environment in the muscles. This change in pH affects muscle function in several ways. Specifically, the accumulation of hydrogen ions can interfere with the contraction mechanisms of the muscle fibers, disrupt calcium signaling, and alter enzyme activity. This phenomenon contributes to what is known as intrinsic muscular fatigue, where the muscle becomes less capable of sustaining high levels of exertion due to the biochemical changes associated with acidosis.

In the context of exercise physiology, intrinsic muscular fatigue is a key factor that limits performance during high-intensity activities. It particularly manifests as a decline in force production, reduced power output, and an overall decrease in the muscle's ability to continue performing optimally.