That's not the only new gear involved. In addition to the pull-up bar, free weights, elastic bands and ample open space of the old series, you'll also need several medicine balls, a large, inflatable ...

Yet here I am, 30 days into it, raring for more and astonished to have surpassed so casually my initial goal of two weeks. For those who haven't heard of it, P90X is a series of exercise videos ...