If you’ve tried your best to improve your posture by simply “standing up straight” only to find yourself defaulting to a rounded spine minutes later, don’t feel bad. Slouching is a tough habit to break, and your musculature may be working against you.

Noam Tamir, CEO and owner of TS Fitness in New York City, tells Runner’s World that the anterior deltoids, or “delts,” found on the front of the shoulders, are often more developed than the posterior delts, which are located on the back portion of the shoulders. This, he explains, is due to “lifestyle use.”

“We push a lot more than we pull,” he says. Even when we’re not cranking out push-ups, bench pressing a barbell, or doing planks, we’re pushing on grocery carts, strollers, furniture, and doors. “This imbalance can cause rounded shoulders and poor posture,” he says.

Why Runners Need Rear Delt Exercises to Improve Posture
Forward-leaning shoulders and a rounded spine can be problematic for runners—and not just because of the discomfort it causes while sitting at a desk. “Posture is very important in the mechanics of a runner. It helps them to optimise pace and reduce the chance for injury due to excessive forward-leaning,” Tamir explains.

To fix poor posture, Tamir recommends specifically targeting the rear delts in your strength training—but don’t overdo it. “The rear delts are small muscles and will fatigue quickly,” he says. He suggests picking a couple of the following rear delt exercises for better posture, and incorporating them into your workout.

How to use this list: Select two of the exercises below to incorporate into your strength-training workout. Perform the number of reps listed, resting for about a minute between sets

1. Bent-Over Rear Delt Fly with Rotation

Why it works: “The bent-over rear delt fly with rotation is a great movement because it externally rotates the shoulder allowing for more range of motion and activation,” Tamir says.

How to do it: Stand with feet shoulder-width apart, knees slightly bent, holding a dumbbell in each hand, palms facing each other. Maintaining a flat back and neutral neck, hinge forward at hips about 45 degrees and allow arms to hang straight down. Engage core and draw shoulders down and back. This is the starting position. With elbows slightly bent, lift arms out to sides to shoulder height. As you raise dumbbells, externally rotate shoulders so that palms face forward (thumbs up) at top of lift. Internally rotate shoulders as you lower weights to starting position. Repeat. Do 12 reps.

2. Single-Arm Bent-Over Supported Row

Why it works: This multi-joint exercise incorporates more muscle groups, compared to the other rear-delt isolation moves on this list, which means you can lift a little heavier, Tamir says.

How to do it: Holding a dumbbell in your left hand, stand to the left of a bench (or other stable, knee-high surface) and place right knee and right palm on bench so that you’re in a supported, bent-over position. Maintaining a flat back, neutral neck, and core engagement, allow dumbbell to hang straight down, palm facing in. Engage core and draw shoulders down and back. This is the starting position. Pull dumbbell back and up to hip, keeping elbow close to body. Then straighten arm to return to starting position. Repeat. Do 10 reps. Then switch sides.

3. Chest-Supported Face Pull

Why it works: The chest-supported face pull is another multi-joint exercise for which you may want to grab heavier dumbbells. “These higher weight-bearing exercises can help with balancing out all the anterior loaded movements we do,” Tamir says.

How to do it: Position an adjustable bench to a 45-degree incline. Holding a dumbbell in each hand, palms facing in toward you, straddle bench and lean forward to rest chest against incline. Straighten arms to lower weights directly under shoulders, palms facing down. This is the starting position. Keeping back flat and neck neutral, bend elbows and use upper back and shoulder muscles to pull dumbbells up and back toward shoulders. Then lower to starting position. Repeat. Do 10 reps.

4. Quadruped Single-Arm Rear Delt Fly

Why it works: “The quadruped single-arm rear delt fly activates your core while helping you focus on one side of the delts,” Tamir says.

How to do it: Start on all fours, shoulders over wrists and knees under hips. Keep right palm on the ground, left hand holding a dumbbell. Maintaining a flat back and neutral neck, engage core and draw shoulders down and back. With elbow slightly bent, lift left arm out to side to shoulder height. Lower to starting position. Repeat. Do 10 reps. Then switch sides.

5. Chest-Supported Rear Delt Extension

Why it works: “This exercise helps strengthen the arm-swing motion during a run,” Tamir explains, by strengthening the backward motion, which we tend to neglect.

How to do it: Position an adjustable bench to a 45-degree incline. Holding a dumbbell in each hand, palms facing you, straddle bench and lean forward to rest chest against incline. With straight elbows, draw arms back so that dumbbells are at sides and in front of hips. This is the starting position. Keeping elbows extended, back flat, and neck neutral, use upper back and shoulder muscles to lift dumbbells up and behind hips. Lower to starting position. Repeat. Do 15 reps.

6. Chest-Supported Rear Delt Fly

Why it works: “Because the body is supported in this exercise, you will be able to lift heavier weights for more volume,” Tamir says. This helps to improve your upper-body strength.

How to do it: Position an adjustable bench to a 45-degree incline. Holding a dumbbell in each hand, palms each other, straddle bench and lean forward to rest chest against incline. Straighten arms to lower weights directly under shoulders. Maintaining a flat back and neutral neck, engage core and draw shoulders down and back. This is the starting position. With elbows slightly bent, lift arms out to sides to shoulder height. Lower to starting position. Repeat. Do 12 reps.

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