Mechanical tension refers to the amount of force produced in muscle fibers. When you lift weights, you produce two types of mechanical tension in your muscles: “passive” and “active” tension. Passive tension occurs when your muscles are stretching, and active tension occurs when they’re contracting. Muscle damage refers to microscopic damage caused to the muscle fibers by high levels of tension. This damage requires repair, and if the body is provided with proper nutrition and rest, it’ll make the muscle fibers larger and stronger to better deal with future bouts of tension.
