This kick set is guaranteed to cause some serious burn, but swimmers love it.
I’m not sure who invented "Whistle Kick" but it is a favorite set with our age-group team and now with our Masters team. This is a really intense set for the legs and knees, so make sure you do some warm-up kicking before you start.
Have everyone on the team put on fins and grab a kickboard. When Coach gives the signal, the first swimmer in each lane starts flutter-kicking, and the rest of the swimmers follow at 5-second intervals. After about 30 seconds, Coach will whistle and point to a swimmer who has just turned at the wall. The entire team must kick FAST until the designated swimmer has completed a length of kick. When the designated swimmer completes the length, Coach whistles and everyone keeps kicking but at a slower rate. Coach will whistle again when another swimmer turns, and everyone kicks fast until THAT swimmer completes a length. This continues until every swimmer has been a "designated" swimmer.
If you have a lot of swimmers on your team, this set can be TORTURE, so you might want to make some slight modifications. For example, Coach could put a 6-minute time limit on the set. Or you could designate a maximum of 10 swimmers. Or Coach could promise that the set will end when the first three swimmers hit 400 yards (or 500 yards or whatever). The nice thing about it is that the set can be as tough as you (and Coach) want to make it.