Hardening of the arteries, also called atherosclerosis, occurs when fat, cholesterol, and other substances build up in the walls of arteries. These deposits are called plaques.efinition. Hardening of the arteries, also called atherosclerosis, occurs when fat, cholesterol, and other substances build up in the walls of arteries. These deposits are called plaques. Over time, these plaques can block the arteries and cause problems throughout the body.
CNS fatigue (CNS = central nervous system) is a slightly more convoluted phenomenon, but the term is thrown around frequently in the world of fitness. By itself, the acronym evokes notions of frailty, complication, and extreme caution.NS fatigue (CNS = central nervous system) is a slightly more convoluted phenomenon, but the term is thrown around frequently in the world of fitness. By itself, the acronym evokes notions of frailty, complication, and extreme caution.
Muscle fatigue, or physical fatigue, is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main causes of muscle fatigue. The limitations of a nerve âs ability to generate a sustained signal (neural fatigue) and the reduced ability of the muscle fiber to contract (metabolic fatigue).