Muscle contraction is the activation of tension-generating sites within muscle fibers. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding a heavy book or a dumbbell at the same position.Contractions can have causes that aren't due to underlying disease. Examples include normal pregnancy, natural labour, orgasm or menstruation.
Scientific Tracks Abstracts: Journal of Psychology & Psychotherapy
Scientific Tracks Abstracts: Journal of Psychology & Psychotherapy