COMMISSIONED OFFICER. Commissioned Officers are the managers, problem solvers, key influencers and planners who lead Enlisted Soldiers in all situations. Enlisted Soldiers perform specific job functions and have the knowledge that ensures the success of their unit's current mission within the Army.
The primary difference between chin-ups and pull-ups is that chin-ups are done with a supinated grip, palms facing in toward the exerciser. This sets up the mechanics so that chin-ups, while still primarily a back exercise, also provide a good arm workout, particularly for the biceps.
Do chin-ups. Chin ups work the back and biceps. To maximize the load on your biceps with each rep, start at a dead hang with your palms roughly six inches apart on the bar, and then lift past just your chin so that your upper chest comes in contact with the bar.