What Exactly Is Eccentric Exercise? Trainers & Physical Therapists Break It Down

Eccentric exercise is not, as it may sound, an unconventional type of workout (although, those are great, too). It actually describes the lengthening portion of a strength training movement. Whereas the shortening phase is concentric exercise. (Think: the lifting or lowering of your arm in a biceps curl.)

Eccentric muscle contractions describe the lengthening or lowering phase of exercise. This process is also referred to as negative work1 since the muscle is absorbing energy from an external load, one study explains. 

"Eccentrics, in a nutshell, is the art of lowering a weight as slowly as you can," says Antonio Lombardo, P.T., DPT, physical therapist at Professional Physical Therapy.

While it may seem like the restorative part of an exercise, eccentric muscle contraction is equally essential in building strength. "Since our muscles need to be able to stretch and shorten with control over various loads, it's important not to overlook building that aspect of strength," says NASM-certified personal trainer BB Arrington.

"In an exercise that involves a range of motion—not a static hold like a plank—the muscles undergo a shortening and lengthening phase," Arrington previously told mbg. "The shortening phase is called the concentric phase; the lengthening or lowering phase is called the eccentric phase." 

How to do it: Start in a plank position, with your hands directly underneath your shoulders, lower slowly and with control; hover with your chest above the ground (pictured above).

2. Lowering the arms during a biceps curl

How to do it: After raising the dumbbell up to your shoulders during a biceps curl, slowly lower the weight back down to your side.

3. Lowering down from a pull-up or chin-up

1. Supine hamstring walkouts

How to do it: Start in a bridge position (pictured above); with your weight on your heels, begin walking your feet away from your body. Once your feet are as far away as they can get without sacrificing the correct form, begin walking them back toward your body.

2. Supine hamstring slide-out (unilateral or bilateral)

How to do it: Start in a bridge position; place a hand towel or sliders underneath your heels. With your weight on your heels, slowly slide your feet away from the body. This is similar to the walkouts, but you're sliding instead of walking. You can do this move unilaterally (with one foot) or bilaterally (with both).

3. Nordic drop

How to do it: Begin standing with your feet hips-width apart with a straight spine and tailbone slightly tucked. Step the left foot back, coming into a reverse lunge. On the ball of your left foot, lower your knee so it's just hovering above the ground (do this part slowly.) It's OK to lean slightly forward during the lunge.

2. Reverse Nordic drop

Because it's often overlooked, sometimes people will injure themselves while doing eccentric exercise. Clients tend to do the minimum work possible to lower the weight instead of contracting the muscle slowly and with control, Arrington says. This can lead to injury from improper form. 

"If there is a notable weakness or lack of coordination during eccentrics, a bit more effort and attention to that area would be greatly beneficial," she says. It's also important to note that eccentric exercise tends to leave people more sore than concentric exercise because it causes muscle damage (essential for muscle building).