Here is a quick treading drill you can do as a rest set in between fast pace swim sets.

I usually do a 3 minute tread with these three kicks (1 min each): NO HANDS

Start off with 1 min of scissor kick alternating left / right leg kicks.

Then do 1 min breast stroke kick vertical swimming

Then try to start alternating your breast stroke kicks into left / right kicks which is a way to start your eggbeater motion.

Then start your swim set again resting with tread with no hands.

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