How should a ski boat operator approach a skier who has fallen?

Water skiing is fun and challenging activity that requires some special skills by the boat operator and the skier. 
After falling, the skier should hold a ski up out of the water while waiting to be retrieved, and if necessary waves his or her arms.
The boat  operator should approach the skier slowly to either return the tow line or pick up the skier and should always keep the skier in view and on the operator’s side of the boat.

Because without physical activity, the body has extra "energy" if you will, and so when it is time for bed you are not tired, so you end up staying up all night. also there is probably an effect on your internal clock, which messes with your melatonin production which goes hand in hand with your sleep cycle