i cant help but wonder everytime how the guy got himself positioned on the swissball like that, especially with 135 on his shoulders...that's a feat in itself.
Oh, and Sean, you've got a point when you're saying he isn't doin that for massive quads, but there are many better& SAFER excercises for balance, rehabilitation and motor unit recruitment than squatting on a swissball...wouldn't you agree?
Peace
D