Stand tall with a neutral spine and your feet slightly wider than shouder width apart. Hold a dumbbell in each hand with your palms facing away from you. The dumbbells should be resting just outside of your thighs. This is your start position. Keeping your elbows and upper arms still, bend at the elbows and drive the dumbbells up towards your chest. Exhale as you do this and squeeze your biceps. Reverse the movement to return with control to the start positon, inhaling as you do so. Repeat for the required number of reps (or time).