what is the best way to learn flip turn

Practice, Pratice, Pratice!

go to the deep end at a distance from the wall you feel comfortable doing a complete 360 degree flip, practice just turning over a couple of times until you can turn over straight. Then go to the middle of the pool, swim toward the wall and do a complete flip, repeat until you feel comfortable doing that. gradually move your flip toward the wall being careful you don't flip too close... you may hit your heels on the gutter/wall and that hurts like heck. When you find the distance from the wall where you can plant your feet on the wall when you flip, push off on your back in streamline. Practice that. Then practice pushing off and twisting to your stomach in streamline Don't get in the habit of lifting your head for air before you flip. Duck your head and bend into a pike kinda position as you pull back with your arms, your legs should flip right over and you should end up in streamline on your back. Some folks close their eyes when they turn, I have to keep mine open because if I don't I wobble to the left and don't go over straight. I'm sure others will have good pointers too.

You don't say whether or not you have received any instruction. Presuming that you have, the most important thing to do is to keep your speed up as you approach the wall. The most prevalent problem with people learning the flip turn is their lack of confidence as they approach the turn, which results in a drop in speed which results in failed turns, since you lose much of your momentum in the act of slowing down. Swim at the wall as if you are going to swim right through it. You will not have any means of propulsion as you execute the turn and it is truly amazing how immediately you can slow down just by ceasing to swim, so make the most of what you bring to it (the turn). You will also have to judge where to flip over in order for your feet to meet the wall at the completion of the flip. Don't worry if you are too far away the first time. Practice will allow you to make the judgment automatically.

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