Reverse flyes

It works your middle back and back of your shoulders. It's also my favourite exercise for posture improvement.

Stand in a lunge position (like you would for bent over rows. Keep the chest low.

Start with weights in your hands, your arms hanging down, palms facing inwards. Slowly lift both arms up to shoulder height and then lower. Make sure you don't lift your upper body as you come up.

It is important to keep the chest down or you will be working a completely different muscle.

Squeeze your back as you lift the arms, bringing the shoulder blades towards each other. Do one set of 12 repetitions, completing each rep in about four seconds.