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If you’re anything like me, things like high-tech algorithms and artificial intelligence might give you the heebie-jeebies when you sit down in a quiet place and think about it for too long. And then in the next moment it’s possible to be fascinated by technology without feelings of fear. 

The good news is the newly redesigned CAROL Bike 2.0 falls into the “not scary” AI category, unlike ChatGPT (which, for me, falls into a strange, dark, gray area of technology). But enough about the things that keep me up at night, I know you’re here for the CAROL Bike 2.0 review—the brand’s second generation stationary bike with instant, AI-controlled resistance, and short but intense workouts.

Fitness Pros Testing Latest and Greatest

Here at GGR, our expert product testers are not just fitness enthusiasts, but fitness industry professionals ranging from Olympic athletes to certified personal trainers. 

We’ve ordered, assembled, tested, and written dozens of reviews on indoor exercise bikes from top brands like Bowflex, NordicTrack, and Peloton. OG product tester and GGR founder, Coop Mitchell has now tested not only the original version of the CAROL Bike, but the 2.0 model, as well. 

That said, we think our collective experience with cardio equipment paired with our experience with CAROL will help you decide if the CAROL Bike 2.0 is worth the investment for your home gym. 

CAROL Bike 2.0

Carol Bike 2.0

GGR Score: 4.14 starstarstarstarstar

Product Highlights

  • Commercial-grade exercise bike
  • Made for maximum training 
  • Comes with a wearable heart rate monitor
  • Multi-grip handlebar

Pros & Cons


  • 11” touchscreen with high resolution display
  • AI-controlled resistance
  • Silent belt for a quieter ride
  • Home membership allows for 8 riders


  • Relatively expensive
  • You have to buy a monthly membership for the workouts
  • Only 18 provided workouts

Bottom Line

The Carol Bike 2.0 is a high-tech bike with five grip positions, 18 different short and effective workouts, and more!

A Quick Look at the CAROL Bike 2.0

If you’ve just been newly introduced to the CAROL Bike 2.0 and you’re trying to determine what all the hype is about, let me give you a quick rundown: The CAROL 2.0 is a solid indoor cycle bike with high-tech (and hands-free) artificial intelligence-controlled resistance settings. Not only will you have the resistance level controlled for you (and it will gradually get harder as you progress) the CAROL 2.0 AI-programming is designed around reduced exertion high-intensity interval training aka, REHIT. 

Don’t worry if this is your first time hearing about REHIT—it’s not as widely known as the concept of high-intensity interval training (HIIT). According to the CAROL website, REHIT is an optimized form of HIIT training that offers full cardiovascular health benefits in a fraction of the time it takes to do a regular steady-state cardio workout (or 20 minutes of HIIT, for that matter). 

Before You Buy

  • A $15 monthly membership fee is required to access the AI-personalized workouts and metrics
  • Your membership allows you to have unique user profiles for up to eight cyclists
  • The CAROL Bike comes with a bottle holder and heart rate monitor 
  • CAROL stands for “cardiovascular optimization logic”

Carol Bike 2.0 Video Review

Is the CAROL Bike 2.0 Worth It?

The CAROL Bike 2.0 will not be the best cardio solution for every home gym owner. “The Carol Bike is much different from most studio cycle bikes, not in how it’s made,” says Coop, “but how it’s designed to be used for improved cardiovascular health in short periods of time. CAROL workouts are all about efficiency.”

That said, Coop thinks the CAROL 2.0 is worth the investment for folks who are short on time and also value the data behind their results. On the other hand, Coop’s biggest annoyance with CAROL is the monthly membership. 
“Without the membership, there’s no optimization of resistance, only the starting resistance,” explains Coop, which means you can free ride without a membership, but that’s about it. The monthly membership is $15 per month and does not feature on-demand classes (like Peloton and iFIT) but rather a collection of 18 different workouts and fitness tests.

carol bike 2.0 bike woman seated on bike

Great for:

  • Anyone who needs an option for low-impact cardio workouts
  • Individuals who need quick, time-efficient, and effective workouts 
  • People who like to track performance with high-tech metrics

Not recommended for:

  • Anyone on a tight budget
  • Folks who don’t like the idea of paying for a monthly subscription to access metrics
  • People who prefer studio classes

CAROL Bike 2.0 Specs

Price $2,595
Footprint 45.5″ x 22″
Weight 120 lbs
Weight capacity330 lbs
User height range 4’7”-6’7”
Display 11” touchscreen
Handlebar Ergonomic multi-grip
Resistance Type AI-controlled instant resistance 
Pedals Adjustable toe cages/SPD clips
Warranty 1-year on frame, parts, and components

Workout Experience with the CAROL Bike 2.0

The first thing I wanted to know from Coop’s workout experience was what makes the CAROL 2.0 different from the original. He let me know there are quite a few similarities, but the main difference is the 2.0 is “overall a superior, more refined product,” says Coop. “The last CAROL Bike functioned well, but it definitely felt like a mish-mash of parts. This one feels like a more cohesive, well thought through product,” he adds. 

Coop also notes that the unique part about riding the CAROL Bike is the software and data. The technology gives you a hands-free experience and does not require you to touch a knob or wonder about how hard to push yourself. 

carol 2 bike in use off seat

“Essentially, you press the start button on the monitor and then it takes care of all the resistance. It’s literally plug and play, you just focus on your output,” says Coop. 

“The AI-controlled resistance that turns on at just the right time at just the proper resistance and it learns your performance over time to provide ongoing incremental difficulty is what makes it special,” he adds. 

In addition to the AI-controlled resistance, the other thing that sets CAROL apart from the competition is the signature REHIT workouts, which is a researched1 approach to drastically reducing the amount of time it takes to improve cardiovascular health and overall performance. 

In other words, researchers set out to find an even more time-efficient way to improve health that didn’t require folks to take a 45-minute run or partake in a 20-minute HIIT session, and in the end they came up with REHIT. 

The REHIT formula focuses on two bouts of 20-second sprints in all-out fashion. This allows you to complete a CAROL workout in about 10 minutes, including a warm up and cool down. 

Because of the all-out work you’re expected to do, you will have the option to start with 10-second sprints—with the AI technology incrementally increasing your sprint time as you progress, of course. 

Footprint and Portability

carol 2.0 bike moving

The CAROL 2.0 has a fairly small footprint, and will take up less than 7 square feet in your home gym (or spare bedroom). Although small in size, it’s a mighty machine at 120 pounds. 

However, when you need to move your CAROL 2.0 out of the way, the transport wheels make it fairly easy. The wheels are located on the back of the bike, behind the bike seat. All you need to do is squat down and grab the front stabilizer, tip the bike onto the wheels, and roll it out of the way.  

Durability and Construction

The CAROL 2.0 has a slightly updated look and feel with a powder-coated steel frame and a heavy-duty plastic shrouding around the pedals and flywheel. 

carol 2.0 bike pedal

Although the plastic shrouds were a callout Coop had on the original CAROL Bike, Coop mentions that the belt-drive system (versus chain drive) in addition to the frictionless, magnetic brake will lead to a durable piece of home fitness equipment. 

Just like the original CAROL Bike, the 2.0 delivers solid construction that allows you to “put all of your effort into the bike and it remains stable,” says Coop. That might seem minor, but the idea behind the CAROL is to incorporate 20-second sprints of all-out effort, so it’s worth considering the construction of the stationary bike you’re being asked to go full-out on. 

The Ergonomics

The CAROL website states that the bike accommodates folks from 4 feet, 7 inches to 6 feet, 7 inches tall—and everyone in between. This bike also has a maximum user weight capacity of 330 pounds, which allows a wide variety of riders to use the CAROL 2.0. 

To customize your riding experience, there are stepless configurations and adjustments on both the seat and handlebars, meaning there is no pull pin adjustment, you can make micro adjustments. 

carol 2.0 bike handlebars

The adjustable seat not only moves up and down but also forward and backward to help you customize how close your upper body sits to the handlebars. Speaking of handlebars—you will be able to adjust them, too—the 2.0 now features a five-position, multi-grip handlebar versus the straight bar featured on the original bike. 

The built-in pulse grip heart rate monitor is no longer part of the handlebar design, but we like the fact the multi-grip handlebar gives you more options and control over your training (and body position). Plus, the 2.0 now comes with a chest strap for heart rate monitoring, which is often more accurate. 

Technology Benefits and Conveniences

CAROL not only has AI-controlled resistance levels, the AI technology also learns about your performance and provides the right amount of resistance for you based on your current fitness level and makes it more challenging over time (how cool!).  

Keep in mind that all these incremental changes to resistance are being done without taking your hands off the handlebars—CAROL’s AI processor is powering the changes for you. CAROL predicts when to dial up your resistance and for how long to keep that resistance going. 

The AI technology also manipulates your workouts based on past performance, which means the more you use your CAROL Bike, the more data can be stored about your progress and influence how difficult future workouts will be. 

Coop warns that your baseline starts very low, but it’s necessary to go through these beginning stages so that the CAROL Bike learns your individual output. In addition to CAROL delivering harder resistance levels, here is an overview of other metrics you will see when using CAROL and the monthly membership:

  • An overall fitness score
  • Heart rate (using the included chest strap) 
  • R-R intervals (small changes in the intervals between successive heartbeats)
  • HRV (heart rate variability) measurement
  • Peak Power
  • Energy Output
  • Local and global leaderboard stats

In addition to all the metrics you receive from your CAROL membership, you can also choose to connect to third-party apps like Zwift and Rouvy on the 11-inch high resolution touchscreen.

CAROL Bike 2.0 vs Keiser M3i vs Peloton Bike 

The CAROL really sets itself apart from other bikes like the Keiser M3i and Peloton with under 10-minute workouts. It’s different from the moderate-intensity continuous training offered by a manual free ride or a studio class from Peloton. The CAROL is designed to deliver effective workouts in just minutes. 

However, if you’re not convinced that the AI-powered workouts are right for you, here is a comparison on CAROL’s top competitors:

CAROL Bike 2.0Keiser M3i Indoor BikePeloton Bike
Price $2,595Around $2,450 Around $1,450
Footprint45.5″ x 22″51” L x 26” W x 49” H 59″ L x 23″ W x 53″ H
Weight120 lbs92 lbs135 lbs
Weight Capacity330 lbs350 lbs 297 lbs
ResistanceAI-controlled instant resistanceMicro-adjustable100 levels of micro-adjustable resistance
PedalsAdjustable toe cages/SPD clips Adjustable toe cages/SPD clips Delta-compatible aluminum pedals
Warranty1-year warranty3-year frame warranty, 90 days labor warranty 5 years frame, 12 months touchscreen, components, pedals, and labor

Keiser M3i Indoor Cycle

Keiser M3i Indoor Cycle

GGR Score: 3.6 starstarstarstarstar
Community Score: 5 starstarstarstarstar

Product Highlights

  • Comfortable for people of all heights
  • Durable
  • 350-lb weight capacity
  • Only costs $6.99 for interactive programming
  • Very smooth

Made in USA Made in USA

Pros & Cons


  • Adjustable seat that accommodates people from 4’10”- 7’
  • 350 lb user weight capacity
  • Only $6.99 per month for interactive programming access
  • Extremely smooth ride


  • More than $2,400
  • No built-in screen to view interactive programming on
  • Primitive and small display

Bottom Line

A time-tested exercise bike that lacks modern conveniences but delivers a challenging cardio workout every time.

Peloton Bike

Peloton Indoor Exercise Bike

GGR Score: 4.33 starstarstarstarstar
Community Score: 5 starstarstarstarstar

Product Highlights

  • 21.5" touchscreen for immersive training
  • Live classes and on-demand cycling sessions
  • Leaderboard-style competition
  • Adjustable screen, seat, and handlebars
  • 5-megapixel front-facing camera
  • Bluetooth connectivity

Pros & Cons


  • Immersive experience
  • Access to thousands of classes, challenges, and a large variety of workout options
  • Compact footprint
  • Sleek design
  • Financing options
  • “Try before you buy” option


  • Disappointing warranty
  • Membership is required to use bike
  • Expensive
  • Shipping is not included

Bottom Line

One of the more expensive options for virtual biking, the Peloton Bike is designed to be an all-in-one fitness solution on a high-quality cardio machine. You’re paying not only for the bike, but the unique training experience it makes accessible from the comfort of your home.

Customer Experience 

Firstly, if you decide to invest in a CAROL Bike, you’ll have a 100-day window to try the bike and make sure you’re totally happy with your purchase. And if you’re not, you have over three months to return for a full refund. The return details are not explicitly listed on the website, but from our experience with other brands, you’ll need to make a request so that your return is officially acknowledged by the company. 

Secondly, the warranty for the CAROL Bike misses the mark completely. Industry standard for a good warranty on exercise bikes typically starts with at least 10-15 years on the frame. The CAROL Bike offers a 1-year warranty, which includes everything from the frame to the parts and electronics. This is disappointing and one area that we hope the brand improves in its next iteration.  

It’s also worth noting that CAROL is a U.K.-based company. But don’t worry if you live in the U.S., there is a customer support line for both U.S. and U.K. customers on the brand’s contact page. You can also contact customer support via email at info@carolbike.com

Ordering and Assembling the CAROL Bike 2.0

If you’re ready to add the CAROL to your cart, you will have the option to choose 0% financing for up to 12 months through Affirm if you qualify based on your credit history. This option will be presented after you’ve filled out your shipping information, when you’re prompted to enter your billing information. CAROL offers free shipping (for the continental United States), which is an added bonus when you’re about to drop over $2,000 on a cardio machine

overhead view of carol 2.0 bike

If you want to have your bike professionally assembled, it will cost you an additional $199, but it could be worth it so that your bike is ready to use right out of the package. However, if you decide to skip the professional assembly, you might like knowing that the flywheel, plastic shroud, and the frame’s upright come pre-assembled. You will just need to attach the stabilizers, handlebars, and wire the Android tablet. 

Customer Reviews

It’s worth noting I first went to Amazon to find honest customer reviews, but the CAROL Bike is not sold on Amazon. So, I went back to the CAROL website and clicked through the brand’s featured customer reviews on TrustPilot. 

Customer reviews turned out to be overwhelmingly positive, with 199 reviews and a 4.7-out-of-5-star overall rating. Most of the frustrations I read about were not really for the bike itself but with the technology, app, and WiFi connection. 

Final Verdict of Our CAROL Bike Review

While REHIT might not be everyone’s cup of tea, I think the CAROL Bike 2.0 offers a lot to home gym folks who are truly limited on time and looking for the best exercise for cardiovascular health and most efficient use of their time. 

We know CAROL also has a hefty price tag, which does not make this investment suitable for everyone. That said, here are some benefits we see to buying a CAROL Bike:

  • Hands-free AI-controlled resistance
  • Super time-efficient workouts
  • Metrics like over output and power
  • Accommodates taller and heavier folks
  • Low-impact training for all skill levels

CAROL Bike 2.0 Rating

CAROL Bike 2.0

Find out how home gyms now have the chance to work smarter, not harder in our CAROL Bike 2.0 review.

Product Brand: CAROL

Product Currency: $

Product Price: 2595

Product In-Stock: InStock

Editor's Rating:

CAROL Bike 2.0

Footprint and Portability – 4.5
Delivery and Setup – 4
Durability – 4
Customizations – 4.5
Adjustability and Ergonomics – 4.5
Tech Capabilities – 4
Conveniences – 4
Dynamic Programming – 4.5
Customer Reviews – 4.7
Value – 3.5
Warranty, Financing, and Returns – 3.5
Customer Service – 4
Buy Now

CAROL Bike 2.0 FAQs

Can you use CAROL Bike without a subscription?

Without a monthly subscription, you will not have access to the AI-controlled resistance and incremental progressions, which is what sets this bike apart from the competition.

What is the warranty on a CAROL Bike?

The warranty on the CAROL Bike covers a mere one-year period and can be upgraded to a two-year period for an additional fee.

What are the benefits of a CAROL Bike?

One of the main benefits of the CAROL Bike is the CAROL workouts designed for reduced exertion high-intensity interval training (REHIT). This type of training is quick, efficient, and won’t take more than 10 minutes of your time.


  1. Cuddy TF, Ramos JS, Dalleck LC. Reduced Exertion High-Intensity Interval Training is More Effective at Improving Cardiorespiratory Fitness and Cardiometabolic Health than Traditional Moderate-Intensity Continuous Training. Int J Environ Res Public Health. 2019 Feb 7;16(3):483. doi: 10.3390/ijerph16030483. PMID: 30736402; PMCID: PMC6388288.

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