A submarine at full speed will travel faster underwater than on the surface. The same is true for you while you are swimming. Why? Simple hydrodynamics. When partially submerged, swimmers are slowed by surface tension and water resistance. Underwater there is no surface tension to combat, allowing swimmers to travel two to three times more quickly.

You will never be faster than when you push off a wall or dive in and streamline underwater. Paired with dolphin kicks, you also conserve momentum by using the biggest muscle group in your body – your legs. The bigger the muscle group is, the more blood flows into it, providing additional oxygen and the opportunity to burn increased amounts of energy. Strong underwater dolphin kicks paired with tight streamlines build fitness and increase speed.

 

Underwater dolphin kick has become so important in swim training that we now refer to it as the fifth stroke. It is the easiest place to shave time off your laps and increase caloric burn in the pool. Adding five strong dolphin kicks in tight streamline off every wall will boost your speed and burn an additional 150 calories per practice.

The fifth stroke is one of the few places that a swimmer at any point in their career can continue to make improvements. Watch the technique in action with this video from The Race Club.

 

As always, my door is open for any questions or concerns. Please feel free to email me at [email protected].

See you at the pool,

–Coach John