Super-fit Cameron Diaz once avoided exercise. It wasn't until her mid-20s when filming Charlie's Angels that the actress, now 41, became hooked on exercise, reports The Daily Mail.

She surfs, swims, hikes and goes to the gym regularly. She says she trains hard to stay svelte. Cameron also sometimes runs a mile as fast as she can.

What to try: The upright row exercise is a great way to tone the bicep muscles in the front of the arm as well as the shoulders.

You will need a set of dumbbells or bottles of water or sand.

Stand upright holding a weight in each hand. Your feet should be shoulder-width. Lift the weights towards your chest by bending your elbows and then raising them outwards.

Raise until your upper arms are level with your shoulders and the weights are at chest height. Return to the start position and repeat 12 to 15 times.