Slow-twitch fibers Muscle fiber type that contracts slowly and is used most in moderateintensity, endurance exercises, such as distance running. Somatotropin See growth hormone. Spasm The involuntary contraction of a muscle Or Muscle group in a sudden, violent manner. The principle that the body adapts very specifically to the training stimuli it is required to deal with. Spot reducing An effort to reduce fat at one location on the body by concentrating exercise, manipulation, wraps, etc. on that location.
Research indicates that any fat loss is generalized over the body, however.
Sprain A stretching or tearing of ligaments. Static contraction See isometric action. The physiological state, during submaximal exercise, where oxygen uptake and heart rate level off, energy demands and energy production are balanced, and the body can maintain the level of exertion for an extended period of time. Strain A stretching or tearing of a musculotendinous unit. The amount of muscular force that can be exerted.