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 the elbow and rest the weight on your shoulder.
With the weight overhead and the elbow locked out, keep the core engaged as you bend the knees into a squat, lowering the hips just below the knees. Extend the 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 the 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.