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.
This exercise works the chin and the muscles at the front of your neck, which help support the skin on the jaw line. While doing this exercise, you should feel the neck muscles and chin tighten, says the Shape Your Face website. Raise your lower lip past your top lip, which should make your chin tense and pucker.