Stand with your feet slightly wider than hip-distance apart.
Hold a kettlebell or dumbbell in your right hand, and straighten your arm overhead. If this is too difficult, or you don't have the shoulder mobility, bend your elbow and rest the weight on your shoulder.
With the weight overhead and your elbow locked out, keep your core engaged as you bend your knees into a squat, lowering your hips just below your knees. Extend your left arm out for balance. (The photo on the right is demonstrating the exercise on the other side).
Try to keep equal weight in both feet as you stand up, keeping your right arm straight.
This counts as one rep.
Complete as many rounds as you can on one side in 40 seconds. Alternate sides every round. Rest for 20 seconds.