If you're going to work your vanity muscles (nothing wrong with that), choose exercises that provide fast results. This routine uses overhand, underhand, and neutral grips, which combine to demand more of your biceps and triceps. Also, the multimuscle moves will build your chest, back, and shoulders, says Matt McGorry, C.F.T., who created the routine. (And if you want to ignite new growth, be sure you work these six muscles you ignore--but shouldn't.)
1. Bench Press
Lie on a flat bench. Using an overhand, shoulder-width grip, hold a barbell straight above your sternum, lower it, pause, and press it back up. Keep your elbows tucked so that when you're in the down position, your upper arms form a 45-degree angle to your body.
2. Chinup
Hang from a chinup bar using an underhand, shoulder-width grip. Pull your chest to the bar. Once the top of your chest touches the bar, pause, and then slowly lower yourself. If chinups are too hard, try a pulldown machine instead, and use an underhand grip. (Not seeing the results you want from your workout? Try these eight weightlifting fixes for more muscle.)