The Best New Exercise You Can Do at Your Desk

If you feel like a slouch because you're always hunched over, straighten up with this simple exercise called the serratus shrug. It works a muscle called the serratus anterior, which runs along your rib cage under your arm pit. When this muscle is weak—as it is in most guys—it causes your shoulder blades to tilt forward and down. This results in "rounded shoulders," giving you a permanent slump. But you can strengthen your serratus anterior quickly and easily—in front of your TV or even at your office. And all you need is a chair.

How to do it:

• Sit upright on a chair or bench and place your hands flat on the sitting surface next to your hips.
• Completely straighten your arms so that your elbows are locked.
• Relax your upper back muscles and allow your torso to sink between your shoulders.
• Press your shoulders down as you lift your upper body, as if you were doing a reverse shoulder shrug. Pause for five seconds, then lower your body back to the starting position. That's one rep.

And make your gym workout even better by working these new exercises into your routine:

Best new exercise for bigger arms: The Telle Curl. This move shifts your body to strengthen the weakest parts of your arms—meaning you'll add muscle where it wasn't before.

Best new plank: The Plyo Side Plank. The side plank should be a staple of every man's workout. Once you've mastered it, upgrade to the plyo. It adds a kick (literally) to build even more stabilizing muscle.

Best new abs exercise: The Lateral Roll. You'll hardly move at all, but don't be fooled—this exercise will work your core in new ways to unleash your six-pack, fast.

Find More From MSN Health & Fitness:

• The Essential Over-40 Workout
• Back Pain at Work: Preventing Aches, Pains and Injuries
• The Five-Second Muscle Test
• Bing Search: Seated Workouts