Exercising for fitness and corporate success

New York

AT 6am sharp, Strauss Zelnick's posse assembles at a building on an anonymous block in Midtown Manhattan. It's late May, and we're going to see Rafique "Flex" Cabral, an instructor Zelnick and his crew first met when Cabral was teaching at Equinox Fitness. This morning, Zelnick is paying Flex for his tyranny, meted out in short bursts of jumps, squats, and pushups.

On paper, a session of "high-intensity interval training" - HIIT to the people who love it - seems basic an…