Fitness score 49.2 · +9%
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.
CAROL Bike: your most efficient longevity tool
The shortest, most effective cardio, developed with leading exercise researchers. Two 20-second sprints, five minutes, scientifically proven results.
Minutes of effort. Years of rewards.
Developed with leading exercise researchers, CAROL Bike offers the most efficient VO2max training—boosting your cardiovascular health and fitness in just minutes. In fact, CAROL is scientifically proven to deliver superior fitness and longevity benefits in 90% less time compared to regular cardio. Making it the most efficient VO2max training tool.
What makes CAROL Bike special?
The shortest, most efficient workouts. Our signature Reduced Exertion HIIT (REHIT) workout creates the most potent training stimulus with just 2x20-second sprints. It’s scientifically proven to deliver superior longevity benefits compared to normal exercise—in 90% less 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. Only 2x20-second sprints, 3x a week 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.
How the REHIT adaptation pathway works
CAROL’s AI-personalization helps you push to your limits during the sprints. Like in a ‘fight or flight’ situation, your muscles are forced to mobilize about 25-30% of muscular glycogen—your emergency energy reserve—releasing key signalling molecules (AMPK and PGC-1a), telling your body it must get fitter and stronger.
You develop more mitochondria, your blood plasma volume increases, and your heart gets stronger. Resulting in increased aerobic and anaerobic capacity.
Get meaningful results in just 8 weeks
Get fitter. Improve your VO2max 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%.
Save time. Get all the benefits of a 45-minute run in just 5.
CAROL Bike
Starting at: £2,595 (or £216.25/month with Klarna).
CAROL membership: £19.99/month.
Highlights:
- The only bike fully optimized for REHIT
- 22+ workouts to choose from
- Fully commercial-grade exercise bike
- AI-controlled, motorized resistance applied instantly
- 45.5″ x 22″ space requirement, smaller than your average yoga mat
Looking to use CAROL in your commercial space?
Speak to a member of our team for our commercial offering.
"A groundbreaking piece of exercise equipment"
Join our 35,000+ rider community
Read real reviews from riders who’ve experienced CAROL’s benefits themselves.
From our community, who know us best.
Hear how our community of scientists, fitness thought-leaders and self-optimizers get the most out of CAROL Bike every day.
Discover how CAROL Bike is the optimal fitness solution for biohacker, Dave Pascoe.
Dave Asprey, the father of biohacking on CAROL Bike: “This is real!”
Performance psychologist Dr. Michael Gervais.
Hear from Human Performance Consultant Ben Greenfield, on the habit of working out.
Discover the power of REHIT for optimizing health with Dr. Stephanie Estima.
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.
Fast Delivery. If you live in the mainland UK, get your new CAROL Bike delivered to your door.
0% APR Financing. You can buy your CAROL Bike with Klarna. And pay just £216.25 for 12 months at 0% APR.
HSA/FSA approved. For qualified customers, use your HSA/FSA funds and save 30-40% on your CAROL Bike purchase using pre-tax dollars.
Real riders, real results.
All rider reviewsFitness score 36.3 · +52%
My CAROL Bike has been great to help me achieve greater fitness and power without the time investment but with all the fun!
Fitness score 41.6 · +12%
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!
From the community.
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It clears my head completely.
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Join our 35,000+ rider community.