"The racers start on the beach, swim out through the surf and back, then repeat paddling a surf board with arms only, then repeat paddling a surf ski with a paddle. If there is any sort of swell it can be quite challenging technically, but even in flat conditions, if you have ever had questions about your upper body strength this event will answer them. Between elements they run along the beach; not far but it is on soft, dry sand, and that is brutally hard".
thanks Les, your above re-quoted description is exactly what they were doing; two circuits of each ! that was just on an hour non-stop and flat out. The conditions were very choppy - like a washing machine. Amazing endurance