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Shortest, most effective workouts

CAROL: the best exercise bike on the market

Developed with leading exercise researchers, CAROL Bike offers the shortest, most effective workouts—backed by science. It’s the world’s first home REHIT exercise bike. Delivering the same results as a 45-minute run—in just 5.

What makes CAROL Bike special?

The shortest, most effective workouts

Our signature REHIT workout creates the most potent training stimulus with just 2x20-second sprints. It’s scientifically proven to deliver double the health and fitness benefits compared to normal exercise—in 10% of the time.

Personalized to your fitness and goals

CAROL Bike's AI-personalization means it's suitable for any age and any fitness level. Our AI learns to push you to your limit, applying automatic and instant resistance, to ensure your workouts are most effective for you.

Significant results in just 8 weeks

CAROL Bike is scientifically proven to improve your VO2max by 12%—in just 8 weeks. That's like turning the clock back on your age by 10 years.

A simple habit that works

5 minutes, 3x a week. CAROL Bike workouts are scientifically proven to be the most effective cardio workout—and so easy to fit into your routine. Giving you back time for the things that matter most.

Get meaningful results in just 8 weeks

CAROL Bike's short, effective workouts mean you can achieve double the health and fitness benefits of regular exercise—in just 10% of the time. And the best part—it’s all backed by science.

Get fitter

Improve your cardio fitness by 12%—in just 8 weeks.

Live healthier

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

Lose weight

Burn twice as many calories on CAROL Bike than regular exercise.


Starting at: $2,595 (finance options available through Affirm).

CAROL membership: $15/month.


  • The only bike fully optimized for REHIT
  • 18 workouts to choose from
  • Fully commercial-grade exercise bike
  • AI-controlled, motorized resistance applied instantly
  • 2K resolution, 11″ touchscreen for sharp image quality
  • 45.5″ x 22″ space requirement, smaller than your average yoga mat
  • Compatibility with a wide range of third-party apps (e.g. Peloton Digital, Zwift, Netflix)

Joel Evan
3 months

"The most significant barrier for me is TIME, and CAROL removes that; in just 5-10 minutes, you get a cardio workout equivalent to 45 mins. Absolute game-changer!"

Joel Evan
1 years
Fitness score
Everett Myers
3 months

"I’ve been training for a half marathon and since adding CAROL Bike to my daily routine in the past 2 weeks, my VO2max has gone up 5% already."

Everett Myers
Fitness score
Dr Gabriela Moreno
3 months

"My CAROL Bike has been great to help me achieve greater fitness and power without the time investment but with all the fun!"

Dr Gabriela Moreno
Fitness score

Join our 20,000+ rider community

Read real reviews from riders who’ve experienced CAROL’s benefits themselves.

Good habits start here.

Order CAROL Bike now, try it for yourself—and build a habit that lasts.

100-Day Home Trial

Try CAROL Bike at home for 100 days. And if it’s not for you, return it and get a refund.

Free Delivery

If you live in the mainland US, get your new CAROL Bike delivered for free in 7-10 days.

0% Financing

You can buy your CAROL Bike with Affirm. And pay just $216.25 for 12 months at 0% APR.

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