This is question I’m asked very often. It’s normally asked by a swimmer who’s having a hard time getting their legs to float. Consequently, they resort to kicking harder. Then, because the leg muscles are the largest in the body and use up the most energy, the swimmer gets exhausted very quickly.
In open water swimming, the legs should be used to help balance the swimmer. This often means using a two-beat kick, which means each leg kicks only once for each arm cycle.
But what if I need to kick more to keep my legs up? Well, then you probably have a problem with your body position. When suspended in water, your body will imitate a seesaw. If you push your chest down and forward — as though you are swimming downhill — your legs will rise higher. Voila! Now you can focus on a balancing your stroke using a gentle two-beat kick.
Just make sure that, when you swim “downhill” you don’t bury your head in the water. Push your chest bone down and forward, but keep the water breaking on the crown of your head.
Swim well! Have fun!