Here’s a phrase you may hear your trainer say: “residual force enhancement”. But, what does that mean?
Residual force enhancement (RFE) refers to the principle of stretching a muscle just far enough during the lengthening–or, negative (eccentric)–contraction to cause more muscle fiber activation during the positve contraction, the hardest part of the exercise.
For example, the chest fly. This exercise targets the area that many women have concerns about: the chest, arm, and shoulder areas. RFE is important here because, if you stretch just below the level of your shoulder, you are going to get more strength and flexibilty from the exercise. However, if you stretch a little too much or go too heavy with the weight, you risk a whole host of injuries, such as injury to the rotator cuff‘s ball-and-socket joint.
To do a chest fly safely, keep your head level or elevated in relation your heart–as you should at all times when exercing strenuously. Try a flat bench or a slightly inclined bench tilted at an angle toward the floor. Choose a weight that is light enough not to cause injury. Do long sets; go until you feel a gentle warming sensation. Then stop shortly after the muscle starts to really fatigue–your acromion process is a very sensitive area!
The results of applying RFE to the chest fly? Getting lean with no bulk! I call that “light, long, and lean”!