Efficient movement is more pleasurable movement.

Watch these elephants swim and you will see:

balance (by weighting the 1st quadrant with head and trunk), core powered propulsion (with shoulders and hips connected in a contralateral motion). These elephants were never taught to "pull harder" or "kick harder." They swim using their natural quadrupedal motion (shoulders and hips) and their body's core torso muscles. Human babies use this motion. Easy freestyle swimming is based on this simple human crawling motion as well.