A decade ago, a muscle physiologist named Brendan Gurd published a study comparing sprint interval workouts with longer continuous endurance workouts. Some people responded best to the intervals; others responded best to the continuous workouts. The implication was clear: to get the best training results, you need to figure out what type of workout you respond best to.
Those results fit in with a broader push in sports science to move beyond “average” responses and provide personalized training advice that would maximize each individual’s response. But last month, Gurd and his colleagues at Queen’s University in Canada published another paper, the culmination of a long journey in which they concluded that they were wrong—that the individual variation they observed in that 2016 study was a mirage.
Their new conclusions, which mirror the results of numerous studies from multiple research groups around the world studying both strength and endurance exercise, are hard for scientists and athletes (and, to be honest, journalists) to accept. After all, isn’t it obvious that some people get a bigger bang for their…
