Not only does your upper body need to be relaxed, but it also needs to be level at all times. Another huge mistake people make is to lean with their head and shoulders. As I mentioned earlier, your power is coming from your lower body, so you want to do what you can to help maintain that power and efficiency. The best way of doing this is to keep your handle, shoulders and eyes level at all points in the course. So, in your deepest lean, your knees and hips will be leaning away from the boat, but your upper body will remain level. Think of playing tug of war — you are digging away in the sand with your knees and hips, but your upper body is level, keeping your eyes on the prize. When you let your shoulders and eyes dip, you are going to become unbalanced, and when you are unbalanced, things come up fast.