Do you regrip?

[Brandon Fisher]

True. My hand loosens but does not open all the way.

[Isshinryu_heart]

I was always taught to keep a tight fist throughout the whole punch, but I know that is not the way the okinawan masters did it. Their philosophy was to be loose and relaxed until impact - thats how they can send you flying across the room with a finger.

[Brandon Fisher]

Thats for sure

[Shokei Marcsui]

I've been taught to keep the arms and hands loose to be able to shoot out quick powerful punches.

[June1]

In general, especially for katas, wherever a fist is to be made, it should be tight. For other techniques, however, it's not necessary, like when you're shadowboxing or something, where you're in more of a natural stance and therefore, more relaxed overall.

[jaymac]

Allowing muscles to be relaxed before execution of strike, provides quick strikes from point A to point B. If you are tight and muscled through the technique, you will be slower in your execution. Tightening just before impact will still provide a powerful strike, block, kick.

[Gyak]

When sparring we are taught to have front hand open, other hand closed. The reason for this is so that you have the added avantage of being able to grab with the front hand. The other hand should be closed ready to fire the gyak.