“I’ve been training for a half marathon and since adding CAROL Bike to my daily routine, my VO2max has gone up 5% in 2 weeks.”
Everett Myers3 months
CAROL Bike — CRO redesign prototype
The world’s first home REHIT bike
The bike that gets you fittest, fastest.
The health and fitness results of a 45-minute run—in just 5 minutes. The shortest, most efficient workout, backed by science.
100-day home trial
0% APR with Klarna
Delivery in 7–14 days
Rated 4.5 “Excellent” on Trustpilot
Reduced Exertion HIIT
5 minutes. That’s the whole workout.
Developed by leading scientists, REHIT delivers the shortest, most efficient workout there is. Just 2×20-second sprints create the most powerful training stimulus—and CAROL’s AI personalization makes it suitable for any age and fitness level.
Discover more about REHIT
One ride · 5:00
Warm up
Sprint · 20 sec
Recover
Cool down
Short
The most efficient workout in just 5 minutes—easy to fit into your life.
Smart
AI-personalized workouts tailored to you—simple to perform at any age and fitness level.
Scientific
Proven to deliver superior health and fitness benefits in 90% less time than regular cardio.
The science
Your results, backed by science.
CAROL Bike is scientifically researched and proven to improve your fitness and health—just 3×5-minute rides a week.
12%
improvement in cardio fitness in just 8 weeks.
10 yrs
improving VO2max by 12% is like turning back the clock on your age.
−62%
reduction in the risk of type 2 diabetes—and blood pressure down 5%.
15 min
burns more calories than a 30-minute run.
The only bike built for REHIT.
Every component is engineered for the optimal ride—suitable for any age and fitness level, with more versatility and choice than most other smart bikes.
AI-personalized
CAROL’s algorithm calibrates every moment on the bike to you.
Instant resistance
AI-controlled, motorized resistance applied instantly.
Commercial-grade
Heavy-duty steel frame, built for professional gyms.
Silent brake
Friction-free magnetic brake—quiet enough for any room.
From £199.58/month at 0% APR with Klarna · £300 off with code LABORDAY
Beyond REHIT
One bike, every ride.
In Free Ride mode, train as you would on a traditional indoor bike—full control over timing, resistance, intensity, and target power. Premium membership adds LES MILLS and music-driven classes.
ZwiftKinomapPeloton DigitalNetflixDisney+YouTubeLES MILLS
Hear it from our riders.
Rated 4.5 “Excellent” on Trustpilot.
Everett Myers3 months
“In 4 months my VO2max is up about 12 points and my heart rate is down 10 bpm. With a history of heart issues, these improvements are huge.”
Matt Nguyen4 months
“Greater fitness and power without the time investment—but with all the fun.”
Dr Gabriela Moreno1.5 years
“Dropping 2.6% body fat in ~8 weeks for someone who already prioritizes a healthy lifestyle is no easy feat. A gamechanger.”
Peter Bauman9 months
“The ultimate biohack. More cardiovascular benefit in 5 minutes than my old 30-minute runs—and faster recovery too.”
Germany Mayfield9 months
Real riders, real results.
Our riders are at the heart of everything we do. See the real impact of CAROL Bike from the people riding it every day.
From the people who know us best.
Scientists, fitness thought-leaders and self-optimizers on how they make the most of every workout.
Biohacker approved
Dave Asprey on why CAROL Bike is the smartest workout for self-optimizers.
“I love my CAROL Bike!”
Dr. Michael Gervais on building a habit that compounds with high-performance routines.
A 45-minute run, in 5
Ben Greenfield on the science of REHIT and maximum cardiovascular benefit per minute.
“Most Innovative Exercise Bike”
Garage Gym Reviews on why CAROL stands out from every other smart bike, 2022.
Good habits start here.
Order CAROL Bike, try it at home, and build a habit that lasts.
100-day trial
Try CAROL risk-free for 100 days. Not for you? Return it for a full refund.
0% APR financing
Buy with Klarna and pay just £199.58/month at 0% APR.
Delivery from £99
Arriving in 7–14 days.
Fitness advisors
Every expert holds an MSc in Exercise Science—here to help you reach your goals.
CAROL BikeSave £300 · LABORDAY
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