In bodies, a movement anywhere will send out a wave of response through the structure: the whole body participates, and the better organized it is around the skeletal core, the more clearly it reverberates. A person whose musculature is either slack or bound by excessive tension cannot act either as delicately or as powerfully as one that reverberates more freely.
Alexandra Pierce, Expressive Movement: Posture And Action In Daily Life, Sports, And The Performing Arts
biology, kinesiology, physiology