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Stop using reverse grip

“The most common problem with the mixed grip deadlift is the vulnerable position it places the underhand side into at the shoulder girdle. As the shoulder externally rotates and hand supinates to achieve the underhand grip, the shoulder is thrown into a more forwardly protracted position.

This forward shoulder position in combination with a supinated hand position places increased stress through the biceps group, especially the long head of the biceps that crosses the front side of the true shoulder joint aka the gleno-humeral joint.”