Potential energy in gait is primarily a function of what?

Potential energy in gait is primarily a function of what?

• A. Mass and velocity
• B. Step length
• C. Position/height of the COM
• D. Time of stance phase

Answer: (C)

The key idea is that gravitational potential energy depends on how high the body's center of mass is. Since gravitational potential energy is U = m g h, where h is the vertical height of the center of mass, the height is the primary factor. The mass m sets the overall energy level, but how energy changes during gait tracks the up-and-down motion of the COM, not the speed. Velocity relates to kinetic energy (1/2 m v^2), which varies with speed, while step length or the timing of stance doesn't dictate the height of the COM. In walking, the COM rises and falls, so potential energy increases when you lift the body and decreases as you lower it, often exchanging with kinetic energy to make gait more efficient.

The key idea is that gravitational potential energy depends on how high the body's center of mass is. Since gravitational potential energy is U = m g h, where h is the vertical height of the center of mass, the height is the primary factor. The mass m sets the overall energy level, but how energy changes during gait tracks the up-and-down motion of the COM, not the speed. Velocity relates to kinetic energy (1/2 m v^2), which varies with speed, while step length or the timing of stance doesn't dictate the height of the COM. In walking, the COM rises and falls, so potential energy increases when you lift the body and decreases as you lower it, often exchanging with kinetic energy to make gait more efficient.