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CAROL Bike increases the maximum amount of oxygen you are able to use during exercise – your VO2max – by 12%.

VO2max is the main measure of fitness. The higher your VO2max, the fitter and healthier you are.


A study by Western Colorado University split participants into 2 groups. Group 1 did 3x short Reduced Exertion HIIT (REHIT) workouts on a CAROL Bike each week; while Group 2 did 5x 30-minutes of moderate-intensity continuous training.


In just 8 weeks, the CAROL Bike group increased their VO2max by 12.3%, the other group by only 6.9%. That’s close to double the improvement—in 90% less time.


Read the full study here.

Live Younger

Improving your VO2max by 12% is like turning the clock back on your age by 10 years.

Live Healthier

Reduce your risk of type 2 diabetes by 62%—and blood pressure by 5%.

Next-level HIIT

Why Reduced Exertion HIIT (REHIT) is the most effective workout.

Time to thrive

Make the most of your time with CAROL Bike's short and efficient REHIT workouts.

Maximum Metabolism

You’ll burn more calories on a 15-minute CAROL ride, than a 30-minute run.

Boost your brainpower

Get fit, stay sharp: how high-intensity exercise and BDNF benefit your brain.

12 benefits of cycling

Regular cycling can help strengthen your heart and lungs, reduce the risk of certain types of cancer, and more.

Demo: How to do REHIT on CAROL Bike

Explore a hands-on guide to doing REHIT on CAROL Bike, showcasing its efficient, effective workouts tailored for every fitness level.

What is a REHIT workout?

Explore REHIT, the game-changing workout that redefines time-efficient training with just 2x20-second sprints.

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