The muscle-up begins with the arms extended above the head, gripping a hold in the overhand pull-up position. The hold is usually a chin-up bar or gymnastic rings.
The body is then explosively pulled up by the arms, with greater speed than a regular pull-up. When the bar approaches the upper chest, the wrists are swiftly flexed and supinated to bring the forearms above the bar. The body is leaned forwards and the elbows are straightened by activating the triceps. The routine is considered complete when the bar is at the level of the waist and the arms are fully straight (never lock your joint out it can cause serious lasting damage).