The Carol smart exercise bike is a $2,400 paradox

If you had the opportunity, would you pay more in order to use an exercise bike less frequently? That is, give or take, the sales pitch for at-home spin bike. It’s the anti-Peloton, designed to be used for just 8 minutes and 40 seconds per workout. At the end of its standard program, it even tells you that you can go to the gym if you want to, rather than because you need to. But stealing back all of those hours from the capricious gods of exercise comes at a price: $2,395, plus $12 per month after the first three months. It’s up to you to decide if that eye-watering fee is worth swerving all of those cardio sessions.

Science

Carol leverages the principles of Reduced Exertion, High Intensity Interval Training (), a variation on the Tabata method of HIIT. Put simply, you’re asked to exercise at a very high intensity for a very short period of time, rather than a long period of time in a steady state. In this example, Carol says that its standard sub-nine-minute workout gives you the equivalent workout to a 45-minute jog. This involves you going all-out for 20 seconds, but then having the better part of three minutes to recover.

That 20-second frenzy is designed to deplete your body’s stores of glycogen and pushes the heart rate through the roof. The long recovery time is designed to reset your body, enabling you to grind out far more from your muscles than you would in a standard Tabata workout. And have shown that, at least in male participants, a six-week can improve their insulin resistance and oxygen consumption.

“One of the things I like about REHIIT is the long length of the recovery periods,” says Stuart Moore, trainer and owner of , a specialist cycling practice. “This enables people without a lot of experience to recover properly between bouts of hard work and then go again with another round.” He added that “all interval training can be useful,” but stressed that would-be adopters “should get the important checks with your doctor” before trying this sort of thing. “I’d prefer complete beginners to interval training try something more mild than modified versions of HIIT,” he said, “this could help with developing a base before delving into the more intense exercise later.”

Andrea Speir, co-founder and lead trainer at , added that the psychological benefits on neophyte exercisers were crucial. “Because it spikes the heart rate and improves VO2 Max, cardiac output and boosts the metabolism […] without being too strenuous,” she said. “It’s not as daunting to commit to it three-to-five times a week, which is where you really see great results,” she added.

History

It’s not often that a company founder announces that their product exists because of a BBC documentary, but Carol isn’t exactly a standard Silicon Valley story. Co-founder Ulrich Dempfle was a management consultant working with the UK’s National Health Service on behalf of firms like McKinsey and PWC. Part of his role was to look for ways to encourage people to exercise more, despite the fact they would often say they didn’t have enough time to become gym bunnies. It wasn’t until he watched 2012’s that he became a convert to REHIIT.

The documentary was fronted by Dr. Michael Mosely, who is chiefly responsible for making intermittent fasting mainstream in the UK. One of Mosely’s gimmicks has always been to look for more efficient ways to feel healthy, and this was a love letter to REHIIT. Dempfle and his team contacted the academics whose research was featured in order to get a look at their equipment. Dempfle explained that the bikes featured had their intensity controlled by one of the academics while a person exercised on them, and that the price was astronomical. It was here that the idea of building an affordable REHIIT bike was more or less born. In fact, Carol would wind up being featured in a Mosley’s 2018 follow-up documentary, , albeit not named because of the BBC’s rules against product placement.

Bike

At first glance, Carol could be mistaken for pretty much any at-home exercise bike. It has a very large, rear-slung flywheel and a beefy drive unit, which houses the system to electronically control the resistance, the secret sauce behind the REHIIT program. A pair of short handles with the customary heart rate-monitoring electrodes sit below the display housing, which holds a 10.1-inch screen. The seat height and distance is adjustable, as well as the height of the handlebars, and there are toe cages and clips on the pedals, for pro cyclists.

After you’ve registered, you can then log in to the bike, which is a process you’ll have to do every time you want to use it. After the first attempt, you can just tap on your initials on a list of stored users, but there’s no way to stay logged in by default. Given how beefy the bike is, and that it’s designed for both at-home and professional use, I feel as if this makes it well-suited to offices and gyms, more so than people’s homes. You could easily see this in the corner of a small business, with staff members getting their 10 minutes each day as they take a break from their work.

Display

When it comes to screens, there are two schools of thought dominating the at-home fitness market. Peloton’s ubiquity means that consumers may soon expect all machines to have a glossy, massive HD display as the default. Companies like Wattbike, Concept2 and others, however, are happy pushing out machines that still leverage old-school LCD head units. (On a personal note, the Polar View offered by the Wattbike PMB is one of the best training tools I’ve ever encountered).

Carol splits this difference by offering a 10.1-inch color touchscreen that offers the same sort of data you’d find on an LCD set, but cleaner and more colorful. The UI flashes an angry red when you hit the high intensity phase, and the visualizations showing your power output are great. A software update, too, came through during my review that has made the UI a lot cleaner and smoother than it was before. And, even better, you can use the display to live stream classes from Peloton’s own app, although you’ll need to subscribe to them separately.

Boot the bike up for the first time and you’ll be greeted by a Lenovo splash screen because Carol’s display is quite literally a Lenovo tablet in a housing. On paper, this is genius: An Android tablet should last longer, is more affordable and should be easier to replace than a custom solution. Plus, you can (and Carol does) leverage Google’s pre-built accessibility features for adjusting screen fonts and voice overs that it would take time and money to copy for little-to-no upside.

Not to mention that, because it is an Android tablet, you can run third-party apps through the Play Store, albeit only ones that have been sanctioned by Carol’s makers. So far, that’s just Peloton, but there’s no technical reason that your favorite fitness, or entertainment, app couldn’t wind up on this screen as well. But, for all of those positives, slamming an Android tablet onto a bike and calling it quits still feels a bit lackluster for a bike costing two thousand four hundred dollars.

In use

Once you’ve answered the medical questionnaire, you have to go through six taster sessions for the bike to gauge your overall fitness level. After that point, you’re free to sample the delights that the bike has to offer, including four different REHIIT workouts. I pretty much stuck to the standard program — the reason anyone would buy a Carol bike — but there are other options available. This includes an Energiser ride, which offers shorter, 10-second sprints, as well as 15-minute or 25 minute Fat Burn program, with 30 or 60 sprints, respectively. You also get the option for a Free Ride, with power controlled by yourself, or an Endurance ride with the resistance slowly ramping up beyond your ability to cope with it.

Once you’ve chosen a program, you’re asked to choose from a series of generic audio options but, again, I was advised by the company’s representatives to stick with the default. (This was probably for the best, because the other options are essentially musak.) In it, a calm voiceover talks about how neanderthal man never jogged, they either walked slowly, or ran like their lives depended on it. At the same time, the on-screen coaching tells you to breathe in for four seconds, hold for a beat, and then exhale over six seconds, which is hard to coordinate if you’re bad at multitasking. All the while you’re asked to cycle at a very low level, never exceeding an output of 20 watts or so.

There’s a countdown timer on screen (and a timeline), so it’s not as if you’re not told when the sprints are about to begin. But the narration treats it more like a surprise, talking about the vista when, suddenly, she tells you that there’s a tiger leaping out at you!, and you have to pedal for your life. The screen turns red three seconds before the sprint begins, letting you spool up as you prepare to go hell for leather to escape your predator. Because the resistance is calibrated to your fitness level, it continues to go up after your initial burst of energy to ensure that you’re nicely wiped out by the end of the sprint. Hell, I found that I was flagging at the 10-second mark, and could never get back to my first output peak no matter what I tried.

You may scoff at the idea that biking for just 20 seconds can wipe you out and make any positive impact on your fitness. You begin to feel your legs go as your body suddenly starts to wuss out, and the final quarter of the sprints have you running on fumes. As effective exercises go, the system makes good upon its promises, and you need that long recovery time to restore any sense of humanity you may have had. The screen will graph your output (and compare it to your output on the second sprint, when you hit it) and let you see how far you’ve dropped between runs. Although the on-screen display’s promise that you won’t sweat is mostly true, it’s not entirely fair for boys like me.

Wrap-up

In the period in which I was using Carol, I think my fitness did improve, as did my mood when I was trying to complete one of these more or less every single day. (The bike repeatedly advises you, as does its representatives, to only do a single sprint session in a 24 hour period and only three times a week to avoid injury.) You certainly start the day feeling more energized, and I can’t complain that this has eaten a big chunk of my day when it hasn’t.

But I’m finding myself hamstrung by the price, especially given the fact that it’s designed to do one job, one fitness program, to the exclusion of most others. Do I want to spend $2,399 plus an additional $12 a month on an appliance I’d use for 30 or 40 minutes a week? Yes, that’s less than you can spend on a or Peloton Bike+, but it’s still a lot. In that philistinic sense of knowing the cost of something but not its value, the numbers make my eyes water.

It’s a bike that does one thing, really, and it does it well, but I feel in my gut that I’d have an easier time singing this thing’s praises if its price was just below the $2,000 mark. It’s a weird psychological barrier for sure, and maybe you’re scoffing at my imaginary parsimony. But as much as this thing is designed for a mainstream audience, right now, it’s priced at the level where only enthusiasts can buy it.