Isometric workout

Using five-to eight-pound weights, perform 15 to 20 reps of each exercise and go from one move to the next with little or no rest between. Do two or three sets three times a week.
Hold it right there: Build strength with this muscle-isolating isometric workout.
Four Top-Tier Moves
1. Reverse fly

Grab a pair of dumbbells and stand with your feet hip-width apart and your knees bent. Bend forward at the hips and let your arms hang straight down from your shoulders, palms facing (a). Raise both arms out to the sides as you squeeze your shoulder blades together (b). Return to start. That's one rep.
2. Biceps curl

Hold a pair of dumbbells at your sides, palms facing forward, and keep your back straight and chest up (a). Without moving your upper arms, bend your elbows and curl the weights toward your shoulders (b). Slowly lower the weights back to the starting position, straightening your arms completely. That's one rep.
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3. Dumbbell cross jab

Stand with your feet a bit wider than hip width and knees slightly bent. Hold the dumbbells at chest height with elbows bent and palms facing each other. Extend your left arm across your body until the weight is in line with your right shoulder (a). As you return to start, repeat with the right arm (b). That's one rep.
4. Lying triceps extension

Lie face-up on a bench and hold a pair of dumbbells above your head, arms straight and palms facing each other (a). Without moving your upper arms, bend your elbows to lower the dumbbells until they are at either side of your head (b). Pause, then lift the weights back to the starting position. That's one rep.