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.
Fatigue, in medical terminology, refers to the state of reduced capacity for work or accomplishment following a period of mental or physical activity. For example, muscles fatigue if the are called upon to repetitively work for an extended period. Most of the causes of tiredness are also associated with fatigue. A related term is lethargy. Lethargy refers to a state of lacking energy. People who are experiencing fatigue or tiredness can also be said to be lethargic because of low energy.