2. One-arm rows
By working on your posture and banishing rounded shoulders, you’ll naturally look longer and leaner. This exercise strengthens your back muscles to improve posture while targeting your biceps and shoulders. Grab a dumbbell with your right hand, palm facing the body. Take a giant step forward with your left leg into lunge position. Bend the left knee and straighten your right leg behind you, coming up on your toes. Rest your left elbow on your left knee and take a moment to straighten your back. Keep your upper body steady as you tighten your stomach and bring the dumbbell up towards your armpit. Slowly lower down until your right arm is straight and repeat eight to 15 times for three sets on each side.