CAROL exercise bike

A buddy of mine picked up this bike at the recommendation of a personal trainer friend of his. To me it appears a bit gimmicky? It claims an AI approach to training to get the most out of a workout. When i watch the review videos, it appears to just be low intensity workouts with some super sprints. That doesn’t seem like its laying out any new ground physiologically. And while it does seem to produce “results” (one must define goals before one can claim to achieve them), I’m not convinced it’s anything other than an AI sticker slapped onto an expensive bike.

Does anyone else have an opinion on this bike? Is it just the new hotness, or is there something else there, technology wise, that I’m missing?

I saw some information and looked at the science some and I can see how it ‘should’ work.
My question is can’t TR make a workout that does the same thing?

From their web site:

Our scientifically-validated REHIT workout is 8 minutes 40 seconds, total. That’s two 20-second maximum intensity sprints, plus warm up, recovery and cool down time.

Your ride is completely controlled and personalized for you by CAROL’s AI. The resistance is set and automated for you — so you can hit your maximum intensity and get faster results.

The question is - why do you have to buy a bike or AI to do this workout? Go walk/jog for 5 minutes, do a 20 second all out sprint - walk for another 3 minutes, repeat 20 second sprint. You are done and it didn’t cost you more than a pair of sneakers that you probably already own.

I’m sure there are SIT studies that show the effectiveness of 20 second sprints on sedentary people. And I’m sure it’s a million times better than doing absolutely zero exercise.

I had a CAROL bike also.

I was coming out a marriage where my pre-marital exercise penchant had been somewhat crushed, and I wanted to re-acquire fitness lost in my marriage as fast as is scientifically possible.

To this end, or for people who don’t have time to exercise and want to stay healthy (in the true sense of the word), then CAROL is an excellent choice.

No, I don’t think TR can mimic it, because it requires deducing what somebody’s peak wattage is over the first 3 seconds or so of a sprint, and ensuring the resistance jumps from a paltry 20 watts or so, to whatever their peak is. They then need to maintain as much of that as possible for the remaining seconds of the 20 second interval.

So what’s so great about that? Well, as I understand it, the CAROL program is a further development of a training program used by the British Olympic Track cycling team, as shown in a BBC program by Dr Michael Mosley, whereby the British team did a light 3 minute warmup, and x3 30-second sprints all-out, followed by 2 minute light spinning. Some research went in to tweaking the protocol and AFAIK this resulted in the CAROL protocol.

Can you achieve the same via running sprints? No - you just cannot load up the leg resistance enough to deplete all the glycogen in the legs, which is key. And trust me, if you truly do go all out on CAROL, your legs are basically jelly at the end of the 20 second sprint. You are spent, which is why it’s spin is at a paltry 20W, which might seem eerily hard after the sprints. In a few short weeks, my near 50 year old untrained sprint went from about 600W to 1000W with the ability to keep it above 600W over the entire 20-second sprint. The point here is: the magnitude of the stimulus relates to the magnitude of the adaptation, and thus it forces certain improvements in various health factors.

It does not however, help you gain the ability to perform long efforts at near FTP. The adaptations are somewhat geared to health/fitness improvements that you can measure in terms of RHR, blood pressure, diminishing insulin resistance, and so on. Trying to make you a better cyclist it is not.

CAROL does have some interval sessions for fat-burning, which I found effective.

But little of it helped prepare or improve my real-world cycling (except for sprinting of course). There’s an element of truth in that you should train doing you want to be good at. You wouldn’t practice pole vault if you want to be a marathon runner because the training stimulus to your body and the sport discipline mismatch. So in this sense, CAROL was not good for being a cyclist. It could make you a good sprinter, or good attacker due to intervals, or even a very healthy and generally fit individual, but that’s it. The programs were fixed durations, and you couldn’t connect it to any services like TR or Zwift and use it for general cyclist training. I couldn’t bridge that mismatch.

My bike also failed 3 times in 6 months with some servo that adjust resistance as you cycle the programs. After the 3rd time, I requested my money back because it was clear the bike had ongoing issues that needed some redesign to mitigate failures. That, or I was truly unlucky. They did oblige.

Of ourse, I wanted to get in to cycling and be a better cyclist, so I then got a Wahoo Kickr and started out with Sufferfest/Wahoo Systm, then moved over to TR.

I had made great improvements with TR given my weight and lack of cycling history, but then ended up moving and having a lot to sort out before I could resume using TR, including a bout of pneumonia. It’s now been 9 weeks since returning, and I’m seeing rapid improvements even in such a short period. FTP up 3.6% after 1 week, and am about half way across the available progression levels since then. with a new FTP detection. IDK what sort of FTP gain that will translate to. I figure I’ll try an FTP test or AI detection once I max my progression levels.

So there you have it. It comes down to your need. I think very few people would spend the CAROL bike price to regain fitness as fast as the research says is possible. But that’s what it’s for and some fat burning, maintaining optimal health when you don’t have time to do any other exercise, but not much else. I believe it should be redesigned to be flexible enough to adopt a proper cycling posture like Wattbike allow, while also connecting to services like TR, Zwift, etc. Only then could it be considered worth the asking price in my view. So if one wishes to become a cyclist, look elsewhere (Wahoo, TACX, Wattbike, etc) and use something like TR.

You should interpret this as:

  1. CAROL is not a gimmick, but it has a specific niche that well-heeled people might wish to pay for and the effects it has are science-backed (some of it can help athletes train less often but at maximum intensity should they want to)
  2. It’s not going to make you a cyclist, you need to provide stimulus of doing the type of cycling you want to be good at in addition to training sesions that elicit particular neuro-muscular effects.
  3. The British Cycling Teams training using a similar protocol matches their sport: glide around a track slowly and then suddenly go flat-out ballistic until the finish line is crossed, which also matches what CAROL could be used for - track cycling.
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