Everyone is familiar, at least hand-wavingly, with the distinction between slow-twitch and fast-twitch muscle-fiber types. The former are great for running marathons; the latter are ideal for ...

TOOLBOX: “We’re all individuals” shouted the mob outside Brian’s window in the Monty Python classic ‘Life of Brian’. Nowhere is that truer than in how athletes respond to training. Two riders may look ...

When you picture different athletes—marathon runners, gymnasts, and Olympic weightlifters, for example—you likely categorize them instinctively by their height, size, and build. But the differences in ...