its all mind and muscle control, you dont have to have really big pecs to do it...its kinda like flexing your bicep practiced for like 3 months and i can do it to the beat of a song
work out do anything which puts strain on your pec musclesthe way to beef up muscles fast is to overload them, kee going long after you feel like you cant stop bcause when your muscles repair...
Its GREATLY affected by the surface it bounces on!If you bounce it on a soft or cushioned surface like a shag carpet, the carpet will absorb a lot of the impact, and the ball will not bounce as high....