Internal torques are generally created by what?

Internal torques are generally created by what?

• A. Gravity only
• B. Muscle activation resisting or controlling external torque
• C. Ground pushing on the foot only
• D. The opposite limb only

Answer: (B)

Internal torques are moments produced by muscles crossing a joint, and they are generated to resist or control external torques acting on that joint, such as gravity or ground reaction forces. This means muscle activation serves to oppose the external forces trying to rotate the joint, stabilizing or moving the body as needed. For example, when standing, the muscles around the ankle activate to counteract the tipping effect of gravity; when lifting a weight, the arm muscles generate a torque to control the forearm’s rotation against the weight. Gravity itself and ground forces create the external torques, but the internal torques come from the muscles resisting them. The opposite limb or forces from the ground aren’t the sources of internal torque themselves, and gravity doesn’t directly create internal torque without muscle action.

Internal torques are moments produced by muscles crossing a joint, and they are generated to resist or control external torques acting on that joint, such as gravity or ground reaction forces. This means muscle activation serves to oppose the external forces trying to rotate the joint, stabilizing or moving the body as needed. For example, when standing, the muscles around the ankle activate to counteract the tipping effect of gravity; when lifting a weight, the arm muscles generate a torque to control the forearm’s rotation against the weight. Gravity itself and ground forces create the external torques, but the internal torques come from the muscles resisting them. The opposite limb or forces from the ground aren’t the sources of internal torque themselves, and gravity doesn’t directly create internal torque without muscle action.