This exercise isolates the chest and can also help with flexibility. However, it should not be used with heavy weights or undertaken by beginners, because of the stress that it places on the shoulder girdle.

1 Grasp a light-to-moderate pair of dumbbells, then lie back with your arms extended up over your upper chest. Your elbows should be slightly bent and your arms facing each other. 

2 Inhale, then slowly lower your arms out to the sides of your torso in a semi-circle - keep the movement under control with your elbows still slightly bent - until there is a full, comfortable stretch in the area of your chest and shoulders around the level of shoulder-height.

3 Hold the stretch for a second before bringing the dumbbells back in to meet at the top of the movement - exhale as you return to the starting position.