Learn Qi Gong
Basically there are 2 types of qi gong exercises. First of all, there are Internal qi gong exercises, which are basically exercises for health. And then there are external qi gong exercises where you break bricks, bend metal etc. What most people don't know is, that it is not necessary to do any internal qi gong exercises in order to be able to perform external qi gong. All you need for external qi gong is exercises to harden your shins, hands, etc, right technique. Of course concentration is required also, because if you can't concentrate and hit slightly wrong, you will injure yourself. Internal qi gong exercises are a meditative exercise forms. In many Chinese martial arts shows, (eg: the shaolin shows) meditative exercises are done before the ternal qi gong acts. These internal exercises mostly for show. You only do them to clear our mind and concrate on what you are going to do to, but they don't create some extra secret power. But yes, concentration is important.