This has got to be the stupidest thing I've seen in years.
So this is a new and improved way to workout? Yeah right.
You won't be able to do anything when your compound fracture your ankle. Not to mention when you do fall off screwing up your back so bad you can't stand straight up for 6 months.
I've seen stupid shit like this before but not as dangerous.
It's just GIMMICKS, GIMMICKS, GIMMICKS.
Wait till someone really fucks themselves up bad and end up suing the trainer, the gym, and the Swiss Ball manufacturers and ends up with millions.
Then and only then will people get smart about stupid gimmickry fads like this shit.