Tone your abs with this highly effective super Tabata [1] workout from Equinox trainer Raneir Pollard [2]. He plays around with the length of the intervals to truly push your core. And be forewarned: he's also a comedian, so laughing is part of this workout, too.

Credits: On Raneir: Under Armour shirt [3], Rhone shorts, [4] and Nike shoes [5]. Manduka mats [6].