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Feel the beat—championing heart health

Build a healthy home for your heart and promote longevity through Reduced Exertion HIIT—the most efficient way of improving VO2max. Get there quicker with CAROL Bike. Giving you the shortest, most effective workouts.

Matters of the heart

Worldwide, heart disease and strokes are the leading causes of death. But at the heart of it—80% of all cases of cardiovascular disease are preventable. It’s time to take control.


Reduced Exertion HIIT (REHIT) helps you improve your VO2max (the maximum amount of oxygen you use during exercise) most efficiently. And this improvement lowers the risk of cardiovascular disease, as well as promoting longevity.


CAROL Bike workouts give the most effective cardiorespiratory exercise and can help you increase your VO2max by 12%—in just 8 weeks.


A public health problem

Physical inactivity is the biggest public health problem of the 21st century. Insufficient physical activity is the 4th biggest killer worldwide. Low cardiorespiratory fitness (CRF) leads to more avoidable deaths than smoking, diabetes, and obesity combined.

Up to 5 million estimated deaths per year could be averted if the global population were more active.

Graph showing avoidable deaths per category

REHIT promotes heart health

As we’ve established, REHIT is the most efficient way of improving your VO2max, the key measure of cardiovascular fitness. The higher your VO2max, the better your capacity for consuming oxygen becomes—allowing your heart to do more in fewer beats.


Studies have shown that the risk of cardiovascular disease and early death is much lower in people with a high VO2max, compared to people with a low VO2max. Meaning that people who improve their VO2max over time will lower their risk of disease—and live longer.


REHIT helps you live longer

Research has indicated an inverse association between cardiorespiratory fitness and coronary heart disease and all-cause mortality. Meaning the fitter you are, the longer you are likely to live.


A 10% increase in VO2max can reduce the risk of mortality due to cardiovascular disease by 20% and add 2 years of healthy life expectancy.

Graph showing survival probability based on VO2max—the higher your VO2max, the longer you are likely to live.

The most effective workout

Improved VO2max comes with sustained aerobic exercise. But less than 5% of the population meet the recommendations for aerobic exercise. Why? A lack of time. But there is an answer…


CAROL Bike was designed to get you fittest, fastest. And by doing our signature 5-minute workout 3x a week, you can increase your cardiorespiratory fitness by 12%—in just 8 weeks. Improving your heart health and adding 2 years of healthy life expectancy to your lifespan.

CAROL’s AI algorithm learns to push you to your limit, so every second matters.

Got a question? Let's book a call.

All our experts have MSCs in Exercise Science, and they’re here to answer your questions. Whether it’s about these workouts, or the science behind CAROL Bike, whatever’s on your mind—we’re here for you.
Get Fitter

Improve your fitness by 12% in just 8 weeks.

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.

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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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