Studies prove: 3x Reduced Exertion HIIT (REHIT) sessions a week – just 15 minutes – is the most effective workout ever.

The stages of Reduced Exertion HIIT (REHIT)
REHIT gives you double the cardiorespiratory fitness benefits of a 45-minute run—in just 10% of the time. And that’s just the start. CAROL Bike gives you the shortest, most effective workouts possible—backed by science.
“’Lack of time’ is the most often cited reason for not exercising regularly. The short duration of CAROL workouts cannot be emphasized enough.”
Daniel Green
American Council on Exercise