When lifting any weight, you’ve got a concentric (hard) and eccentric (easy) phase. For instance, as you lower into a squat, you’re performing an eccentric action. When you return to standing, that’s concentric. And, according to research published in the European Journal of Applied Physiology, eccentric work is far better at triggering hypertrophy.
To increase the amount of eccentric effort in your workout, you can do two things: either slow down the eccentric phase of each exercise you perform or integrate eccentric-only variations into your routine.
Take the Nitric Force, for example: To make it eccentric-only, you would lower to the floor, and end the exercise there. Note: If you’re trying eccentric-only exercises, you’ll need to substantially increase the weight that you use. Physiologically, muscles are far stronger moving eccentrically than they are concentrically.