Three minutes of sprinting can do something that 90 minutes of moderate exercise apparently cannot: dramatically reshape the molecular contents of the bloodstream. Rockefeller researchers comparing different intensities of exercise found that six sets of 30-second, all-out sprints altered nearly a quarter of the proteins measured immediately afterward. Moderate, continuous cycling for 90 minutes altered fewer than one-quarter of 1%. And while moderate treadmill running changed more proteins than cycling, it still altered far fewer than a quick sprint.