Kick.
Alternate kick kepping in line with the body and close to the water surface. Do not kick too deep. Start the kick from the hips and use the whole of your leg through to your feet and toes with feet and toes pointing towards the opposite end of the pool. (Do not drive or strat the kick from the knees). Knees will be slightly bent with legs and feet pasing close to each other with feet creating a small amount of white water splash. Increase the speed of kick to a six beat leg kick for greater propulsion over short distances (six leg kicks to every full arm stroke cycle). The kick for distance swimmers is mainly used for balance.
World Rugby has reportedly conceded Aaron Smith's disallowed try in the World Cup final should have stood.
"It is not only useful for staff who are experienced but a valuable tool for those subject staff who have to take teams."
The variety of sessions across sports - sometimes we steal session ideas from one sport and use them with another.