Over the years we have received many questions from coaches and swimmers about how DragSox® work. I have written on the subject before, but I thought it might be useful to explain in simpler terms.
As the swimmer moves through water, he essentially pushes a wall of water in front of him. This creates an area of high pressure directly in front of the swimmer. At the same time, as the swimmer kicks, DragSox create holes that water molecules will fill. This creates an area of lower pressure directly behind the swimmer.
When there is a difference in water pressure, the water from the higher area of pressure rushes into the area of lower pressure. The water from the front of the swimmer rushes back to fill in the holes create by DragSox thereby pulling the swimmer backwards. To keep moving forward, the swimmer has to work harder, eventually becoming stronger and more powerful.
The beauty of DragSox is that they maintain the swimmer's body position. All other resistance tools — parachutes, stretch cords and such — pull the swimmer back and affect the swimmer's body position to some degree. DragSox create natural drag with the water pushing the swimmer back. The physics may seem complicated, but the simple fact is that DragSox make swimmers stronger and faster.
P.S. DragSox were invented by AquaVolo and are sometimes referred to online as DragSocks, Drag Socks, The Socks, or simply Sox.