In the 1930s, a German coach named Woldemar Gerschler came up with a novel idea to help runners better manage their time. He discovered that they could accomplish more in a given stretch if they broke it down into discrete chunks of running, followed by brief breaks. For instance, you’ll run faster, farther, and with better form if you run hard for six sets of seven minutes, each one followed by three easy minutes, than if you run for 60 minutes consecutively. Gerschler used this style of training to guide multiple runners to Olympic medals, and it wasn’t long before it spread throughout running and eventually into just about every other sport as well. By the 1960s, Gerschler’s method — what came to be known as “interval training” — was the predominant training system across elite sports, and it still is today.
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