Which COP trajectory metric describes the magnitude and speed of corrective actions?

• A. Magnitude and speed of corrective actions; larger values indicate reduced stability
• B. Cognitive load and attention
• C. Visual acuity during balance
• D. Auditory processing

Answer: (A)

The main idea is that COP trajectory metrics capture how much and how fast the body must move to stay upright. When balance is challenged, the postural system makes corrective actions, and this shows up in the center-of-pressure data as both the size of the sway (how far the COP moves) and the speed of those movements (how quick the COP travels). Metrics like sway path length, mean velocity, and acceleration reflect these corrections. Larger path length or higher velocity/acceleration mean bigger or faster corrections, indicating reduced stability. The other options point to cognitive or sensory aspects rather than the actual movement pattern of the center of pressure, so they don’t describe the trajectory of corrective actions.