[m0squito]

what muscles do you tense [if any] when doiing an L kick, in order to hold it?

[Anthrax]

the only thing you need in order to hold it is 'Practise'

[bb0y tRu]

Thrax is sorta right but the when you do an l kick you don't tense any muscles. its more the flexibility of your muscle. try doing one against a wall. If your muscles fail before your balance does. than work on your muscle but if your balance fails you first than you know the problem!