Most kids learn to swim flat in the water, with little to no hip rotation. But swimmers who participate in triathlons and open water swims must often change their stroke to involve more side-swimming to conserve energy, to swim faster, and to get through rough water easier.
The method of swimming from side to side as you swim has been around for many years. Mark Spitz was criticized for this movement in the 70s! His critics didn’t realize that science would soon back up this style of swimming and would prove that it was a more efficient way of swimming. Since then, great coaches like Howard Furby and Ernie Maglischo have popularized this method of side-swimming with many successful students over the years.
To swim well is to use your core – chest, lower back, stomach, and hips. The top swimmers know to rotate their cores from one side to the other while keeping their heads fixed. When they rotate in this way, they move through the water like fishes, or boats, and reach maximum efficiency on each stroke.