chin-up v. pull-up

To execute either upper-body exercise, hang by your hands from a horizontal bar with your arms fully extended, pull your body up until your chin is above the bar, and slowly lower yourself until your arms are straight again.

Chin-ups are performed with your palms facing toward you in a supinated grip. Pull-ups are done with your palms facing away from you in a pronated grip. Both exercises help strengthen the arms, shoulders, and back, but chin-ups are easier, focusing on the biceps, and pull-ups are harder, focusing on the back.

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