I know its role in preparing mentally for physical activity...but how necessary is it really? I only ask because when i was in karate i could never focus during meditation (of course i was only 3, but still).
well it depends... if your doing meditation to harm others as your only goel, you may never be able to meditate at all hehe. meditation helps to improve your concentration, memorization, mood, calmness, peace and health... it can also help improve your breathing and be able to properly breathe while in a fight (keeping your calm, cool meditative breathing)... this thread has much better research and arguments explained in the health and philosophy and religion forums
The problem with this question is that everybody will have a different definition of meditation, and some will probably expand that definition to include any sort of mental preparation. The reality is that there are lots of MAs where you don't sit contemplating your navel at the beggining of class and they get along fine without it. In terms of formal sitting and thinking about nothing stuff, it's not important at all.
