Resistance training performed with either low or high ratings of perceived exertion relative to volitional failure results in equivalent increases in maximal isometric knee extensor torque and one-repetition maximum strength when training volume is held constant.

When muscles are trained with heavy loads, the nervous system learns to make the existing muscle fibers fire faster and calls on more powerful muscle fibers when needed. This happens whether the person stops the set early or pushes to near exhaustion, as long as the total amount of work is the same. The result is that the muscle can produce the same maximum force, even if the way it gets there changes.