If you want A-list arms, you've got to go to the source: Hollywood trainer Steve Zim, who has helped sculpt the toned arms of celebs like Laila Ali and Jessica Biel. He created the exclusive 15-minute workout below—based on moves from his book, The 30-Minute Celebrity Makeover Miracle—that, unlike other arm-bulking routines, equally works all the muscles in your biceps and triceps to give you the coveted long-and-lean look. Do these moves 3 times a week; for best results, change the order of the exercises each time.
Stand with feet hip-width apart and arms down by your sides, holding a 5- to 8-pound dumbbell in each hand, palms facing in. In one fluid motion, bend your right elbow and sweep your hand in front of your body and up to shoulder height. Lower straight down, then repeat with your left arm. Do 3 sets of 15 reps per side.
Trainer tip: To keep the focus on your biceps, move your upper arm as little as possible.
Lie facedown with your forearms, palms, and knees on a mat. Your elbows should be directly below your shoulders, with hands and forearms 6–8 inches apart.
(B) Keeping your knees on the mat, straighten your arms and push your torso and thighs up. Your body should be in a straight line from your knees to your head. Slowly lower your body to complete the rep. Do 3 sets of 15 reps.
Trainer tip: To best target your triceps, don't allow your elbows to flare out to the sides during the move.
Holding a 5- to 8-pound dumbbell in each hand, arms by your sides, stand with your feet slightly wider than shoulder-width apart. Keeping your back straight, bend your legs slightly and lean forward from the waist until your torso is nearly parallel to the ground. Raise your elbows until your upper arms are even with your back. Your elbows should be bent to 45-degree angles with your palms facing each other.
Keeping your upper arms still, extend both hands behind you, then rotate your wrists so that your palms are up. Turn your palms back to face each other and bend your elbows to bring weights back toward your body to complete the rep. Do 3 sets of 15 reps.
Trainer tip: Do the move slowly—don't use momentum to raise and lower the weight.