'The rear delts (known as the posterior deltoids) are the muscles on the backside of the shoulders,' says Macy Pruett, CPT, a certified personal trainer and the founder of Fittest Core. 'They sit on ...
Slowly lower back to the starting position. Repeat for 10 repetitions. This exercise targets your shoulders and core — and hits a lot of other muscles for full-body engagement! Start in a full ...