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For the cyclist or triathlete looking to train in a more structured way, indoor training is a must. It allows you to ride hard without interruption, worrying about road surface or other road users.

There are two primary options available for indoor training. One the one hand we have the ubiquitous turbo trainer. This is a device you mount your existing bike onto, providing resistance and power readings. Most modern turbo trainers are also what we call “smart” turbos. These change the resistance for you based on both manual input and that from a 3rd party app.

Next up we have the smart bike. These are a relatively recent invention, with the first Wattbike released in 2008, designed for use primarily by track cyclists. This was updated more recently with the Wattbike Atom, a bike designed for integration with modern training apps. In recent years other manufacturers including Wahoo, Stages and Tacx have launched their own smart bikes to rival this, seeing a gap in the market.

So, which option is superior? A turbo trainer or a smart bike? Of curse, it’s not quite as simple as that, but there are definite pros and cons to each. Let’s start by looking into each in a bit more detail.

Turbo Trainers

Wahoo Kickr Turbo Trainer

When you purchase a turbo trainer, you will be choosing between one of two options, wheel on or wheel off.

With a wheel on trainer you can simply mount the whole bike onto a trainer using a clamp, however there’s a bit more to it than that. You have to make sure the drum the tyre presses against is at the correct tension and the tyre is at the correct pressure. The trainer will also place a lot of wear on your tyres. To get around this many cyclists buy a second wheel to place an indoor specific tyre on, which they will swap out when they ride indoors. As many cyclists will look at wheel on trainers to avoid having to remove their rear wheel, this removes much of the appeal.

Most turbo trainers are wheel off trainers, where you remove the back wheel and place the bike on the trainer itself. The advantages provided by these trainers are a greater potential for creating resistance, quieter operation, improved accuracy, more realistic ride feel and smaller unit size. The only real downside is if you plan to share the trainer with another rider whose groupset isn’t compatible with yours, as the cassette lives on the trainer. A cassette swap is a five minute job with a bit of practice, but it’s a barrier to getting your workout done, especially if you’re not feeling motivated that day.

One downside of all turbos is that by riding your bike indoors, you are putting wear on it. All components have a shelf life, and riding a turbo trainer will place wear on your components. Making sure your drivetrain is clean before placing it on the turbo trainer, and regularly checking your chain length can help with this.

Some frame manufacturers don’t cover turbo use under their warranty, so you may find yourself out of pocket if your bike is damaged on the turbo trainer. Damaging a bike on a turbo trainer is incredibly difficult, and as long as you attach it to the turbo tightly, the chances of damage are incredibly low unless you do something silly.



Next up, we’ll look at what you can expect from a smart bike

Smart Bikes

The Wattbike Atom Smart Bike

There are two very noticeable differences between turbo trainers and smart bikes. The size, and the price tag.

While many turbo trainers can fold up and fit behind your sofa if you are tight on space, a smart bike needs a dedicated space, perhaps even dedicated room to use. They also come in at over twice the prize of a top end turbo trainer. So, what do you get for your money?

Smart bikes are almost silent, due to the absence of a moving parts. While the latest turbos are whisper quiet compared to classic trainers which would give jet engines a run for their money, you still have the mechanical nose of the chain, which smart bikes remove. There will still be some humming as you put down the big watts, but if you have a sleeping baby in the house or live somewhere with thin walls/floors, this could justify the purchase of a smart bike over a turbo trainer.

Smart bikes also require less calibration, due to not only their ability to self calibrate, but the fact they don’t get moved around as often as a turbo trainers do. This means your power readings will be more accurate, if you are using the Smart bike’s power meter. I encourage everyone who uses a power meter outside to also use it inside, overriding the power meter on your turbo/smart bike for more consistent readings, so this won’t be as much of an issue for many.

The big downside to smart bikes for me is adjustability. While you generally have a great degree of freedom to get yourself in the right position with smart bikes, 1mm can be the difference between a great ride and a painful one for some cyclists, so replacing your position fully on a smart bike is an ongoing battle for many. A little higher, a little shorter, try a little lower again, the tweak are often endless, especially if sharing with another rider and you have to adjust each time you ride. One client I’m working with was using a smart bike, but the fixed crank length on his model meant it exacerbated a hip issue. As a result, he had to sell his smart bike and buy a turbo trainer.

Getting the basic measurements (reach, saddle height, frame size) right can take a bit of work, but once you look at replicating a TT position on a smart bike, you’re in a world of pain. TT positions are incredibly difficult to get comfortable in at the best of times, let alone replicate on another piece of machinery. Getting the stack height, length of bars, angle of bars and gap between the bars millimetre perfect on two separate bikes is maddening. Some smart bikes allow you to use your own handlebars, but the front end of triathlon bikes are not cheap, you’d be looking at around £500 minimum to replicate the cockpit of your aero bike onto your smart bike. When you consider you’re already paying a premium to be riding a smart bike in the first place, any extra expense to get comfortable on it seems difficult to justify.

Some bikes will also have features such as showing your pedalling technique, and automatic adjustments to gradient or road feel. If a manufacturer develops both smart bikes and



Next up we answer the question you came here for. Turbo trainer vs smart bike, which ones wins out?


For my money, the downsides to a smart bike do not outweigh the cost. You may save yourself money on components, but if you consider a chain costs around £20, and you’re paying a premium of around £1000 to upgrade to a smart bike, it’s probably something of a false economy. Getting the position right on them can be incredibly difficult, and they just don’t feel as good to ride. The purchase of a smart bike should come down to the following question:

Will it make you a faster triathlete?

The answer here, compared to to a turbo trainer, is an emphatic ‘no’. Smart bikes have the potential to provide some convenience, but their features don’t justify the price for my money. If you’re primarily an indoor cyclist, are a road cyclist less sensitive to position, or are just looking to get fit at home, smart bikes may well be the product for you.

None of the professional triathletes I know have switched to a smart bike and they’re not aggressively marketed in triathlon media. You may see lots of triathletes on Instagram riding smart bikes, or hear your club mates taking about their flashy new indoor bike, but the root of this is the assumption that the most expensive option is the best option. If money is no object and you want to be the best athlete you can, the £2500 option must be better than the £1000 option. That’s how it works, right?

If you’re torn between a turbo trainer and a smart bike, make the decision that’s right for you, your budget, goals and lifestyle. I don’t want to tell you what to do. However if you’re a happy turbo trainer user, wondering if a smart bike will take your training to the next level, the chances are it won’t justify the investment.

I hope this article doesn’t come across as too negative, I have a lot of love for all the manufacturers of smart bikes, I think they’re great products which do the job they’re designed to do incredibly well. However, the demands on triathlon just don’t line up with the functionality of the bikes, and it won’t be an easy problem for manufacturers to fix.

If you had already justified a smart bike to yourself, you could instead consider some race wheels, an aero helmet, or some coaching. All of which are almost guaranteed to provide more bang for your buck.

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