This is a one-arm triceps extension, which is working the triceps. Sara is keeping her knees slightly back, her shoulders are back, of course, tight, her elbows locked to another side, and there is full range of motion as needed here coming all the way down flexing the triceps and fully flexing it all the way down. Keeping her wrist nice and straight, she exhales as she comes down and inhales as she comes up. You can add variety to this exercise doing the same positioning except for an overhand grip. [Cross Talk - 00:01:04 - end]