Regulation of angular impulse during fall recovery.

Maintaining balance and postural stability while performing functional activities is critical to an individual's independence and quality of life. When individuals are unable to maintain their total-body center of mass (COM) within the base of support, a loss of balance may result, leading to a fall. Effective interaction between the environment and the neuromuscular and musculoskeletal systems allows an individual to generate the ground reaction forces relative to the COM necessary for maintaining and recovering balance during expected and unexpected situations. This article reviews the role of the swing and support legs in regulating angular impulse during fall recovery and contrasts the balance recovery strategies used by younger adults and older adult nonfallers and fallers. Multijoint dynamics and neuromuscular control used during fall recovery are discussed at the total-body, joint, and muscle levels. Understanding the fall recovery mechanisms successfully used by younger and older adults will allow us to begin to identify effective intervention strategies that target specific populations.