This worked 4 me,
Spread ur legs aboutn 2 feet apart,
bend ur knees (as u would if u were goin 2 sit down,)
then jump.
Start off slow and at short heights,
then start goin faster and jumpin higher.
But me tellin u that i was told that u can pull ma tendon by doin this excercise may make u rethink doin it.
But its ur life.
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