The shortest, most efficient workouts
“A groundbreaking piece of exercise equipment.”
“After two weeks of riding the CAROL Bike, I ... love it.”
“For those short on time, it’s worth the investment.”
“If you’re looking to revamp your at-home fitness lineup, CAROL Bike is here.”
“It’s a game-changer for busy people.”
“Engineered to give you the most effective workout in the shortest time possible.”
The results
CAROL Bike's short, efficient workouts are scientifically proven to get you superior health and fitness benefits compared to regular exercise—in 90% less time.
Beyond REHIT, CAROL is a fully customizable indoor bike: Free Ride with control over timing, resistance and target power, plus Zwift, YouTube and Netflix integration.
Inside the ride
Developed by leading scientists, Reduced Exertion HIIT (REHIT) is designed to provide the shortest, most efficient workout. Just 2x20-second sprints create the most powerful training stimulus. With CAROL's AI-personalization making it suitable for any age and fitness level.
Pedal slowly for up to 2 minutes to prep for your first sprint.
AI applies Instant Resistance. You push to your limits for 20 seconds, forcing 25-30% mobilization of muscular glycogen, releasing key signaling molecules.
Pedal slowly for 3 minutes, clearing lactate and preparing for your second sprint.
Push again to your limits for 20-seconds to activate the signaling molecules released in Sprint 1. This tells your body it must get fitter, stronger.
Light pedalling for 3 minutes, so blood pressure, heart rate, and breathing go back to normal.
From our co-founder
REHIT and AI-personalization make CAROL Bike unique. Just 2x20-second sprints create the most powerful training stimulus. Giving you by far the most efficient intervention to increase your cardio fitness.
The hardware
CAROL Bike offers all essential features to make REHIT easy, effective and safe. All components have been meticulously engineered to provide the optimal riding experience.
AI-controlled motorized resistance, applied the moment your sprint starts — no dials, no guesswork.
Every ride calibrates to you, from your very first calibration rides onwards.
Quad speakers with Dolby Atmos, WiFi 6E, Bluetooth 5.2.
Zwift, Kinomap and Peloton Digital, plus Netflix, Disney+ and YouTube on board.
Heavy-duty steel frame, silent poly-V belt drive, friction-free magnetic brake. Built for professional gyms, sized for home.
The future of fitness
CAROL Bike's short, AI-personalized programs are designed to get you fitter, faster. It's the ultimate fitness tool for anyone seeking better results in less time.
Our signature REHIT workout creates the most potent training stimulus with just 2x20-second sprints. It’s scientifically proven to deliver superior health and fitness benefits compared to regular exercise—in 90% less time.
−90% timeCAROL 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.
Any fitness levelCAROL Bike is scientifically proven to improve your cardio fitness by 12%—in just 8 weeks. That’s like turning the clock back on your age by 10 years.
8 weeksDeveloped with leading exercise researchers and scientists, CAROL Bike’s range of scientifically-proven workouts make it the world’s most effective exercise bike.
22 workoutsThe offer
Experience the shortest, most efficient workouts—backed by science.
Try CAROL Bike at home risk-free for 100 days. Not for you? Return it for a full refund.
Delivered to your door, ready for your first calibration ride.
Pay just £216.25/month at 0% APR, with Klarna.
Commercial-grade build, plus a free heart rate chest belt in the box.
Rider results
Our riders are at the heart of everything we do. Discover the real impact of CAROL Bike straight from those reaping the benefits every day.
All rider reviewsI’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.
My CAROL Bike has been great to help me achieve greater fitness and power without the time investment but with all the fun!
In just 4 months, my VO2max has increased by about 12 points, and my heart rate has decreased by 10 bpm. For someone with a history of heart issues, these improvements are huge!
Dropping 2.6% bodyfat in ~8 weeks for someone who prioritizes a healthy lifestyle is no easy feat. I’d go so far as to label it as a gamechanger.
It’s easy to fit a quick 5-minute workout in, especially if you don’t need to shower after your workout!
I get more cardiovascular benefit in 5 minutes than I used to get from 30-minute runs, and my recovery is faster too.
Trustpilot
Read real reviews from riders who’ve experienced CAROL’s benefits themselves.
Exercising smarter with CAROL is improving my health week after week. The AI personalization takes any guesswork out of my workouts, so I continue to be challenged and exceed my goals. I am a powerful example of CAROL Bike’s effectiveness!
The most significant barrier for me and my busy clients is TIME, and CAROL removes that; in just 5-10 minutes, you get a cardio workout equivalent to 45 mins. Absolute game-changer!
CAROL has been a game changer for me. The REHIT Intense ride is revolutionary in the fitness realm. It’s the most effective way to get the fittest, the fastest.
This will help anyone get into the habit of exercising and will also support high performance athletes in reaching higher levels of strength and fitness. I recommend the purchase of CAROL without any hesitation!
The transformative impact on how my body feels has made CAROL my undisputed go-to for cardio workouts. As a sports medicine practitioner, I highly recommend it.
The REHIT program accelerates progress. The built in programming and recording of events creates the ideal feedback loop.
The community
Hear how our community of riders and fitness thought-leaders make the most of every workout with CAROL Bike.
More from the community
Biohacker ApprovedDave Asprey, the father of biohacking on CAROL Bike: “This is real!”
“I love my CAROL Bike!”Performance psychologist Dr. Michael Gervais.
Benefits of a 45-minute run—in just 5Hear from Human Performance Consultant Ben Greenfield, on the habit of working out.
From injury to peak performance“How CAROL Bike helped me regain fitness and reach the top.” — Shauna’s success story.
Before you order
Try CAROL Bike at home for 100 days. And if it’s not for you, return it and get a refund. Trial details
No. CAROL’s AI calibrates every ride to you, so REHIT is suitable for any age and fitness level — your sprints are always yours, never someone else’s numbers.
Delivery from £99. Our team will confirm timing when you order. Delivery details
You can buy your CAROL Bike with Klarna. And pay just £216.25/month at 0% APR. Financing details
