If you've heard your riding mates carrying on about Zwift and smart trainers but you have no idea what they're talking about, let us help.
A smart trainer is a tool you mount your bike on that offers resistance like a normal trainer, but with the added benefit of allowing the resistance to be controlled by cycling apps such as Zwift.
What's the point of a smart trainer?
The boom of indoor cycling apps such as TrainerRoad, Zwift, RGT Cycling and The Sufferfest have created a cottage industry of smart trainers for the simple reason that the tool makes indoor cycling so much more engaging.
When riding a virtual course on a smart trainer, if you begin to climb a hill the resistance ramps up and you have to pedal harder (or change to an easier gear!), just like when riding outdoors. This works with real-life POV video on apps such as Rouvy and FulGaz, as well as digital worlds like Zwift.
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When doing group rides or races on Zwift, the resistance gets easier when you are riding in a group, simulating a draft, and harder when you are alone in the wind.
Similarly, when doing structured workouts, a smart trainer automatically sets resistance to the exact prescribed wattage, so you don't have to worry about gauging or pacing your effort.
So, there are key reasons to use a smart trainer: to make indoor cycling much more fun and more productive.
How a smart trainer works
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Smart trainers communicate on ANT+ and Bluetooth. ANT+ is cycling's standard wireless frequency, so most bike computers, heart-rate monitors, power meters, speed/cadence sensors and such work on ANT+. Bluetooth is native on smartphones and many tablets and computers.
You can 'drive' a smart trainer with a newer bike computer, such as a Garmin Edge 530 or a Wahoo Elemnt Bolt. With this method, you can set the resistance at a particular wattage, complete a workout or ride a previous course.
What is a lot more interesting for most folks is to 'drive' the smart trainer with a cycling app.
With this method, you load the app on your smartphone, tablet or computer, then connect it to your smart trainer via Bluetooth or ANT+.
I recommend using Bluetooth for this connection because it is often more stable and it doesn't require an ANT+ dongle. (The latest Samsung Galaxy has native ANT+, but most phones and computers do not.)
With most smart trainers, you need to plug them in — another difference from a standard trainer. How smart trainers generate resistance varies by model, with many using a combination of a flywheel (like a standard trainer for good road feel), magnetic resistance and an electronic motor/brake.
What you need to use a smart trainer
To get in the virtual cycling game, you need:
- A computer, tablet or smartphone with native Bluetooth or an ANT+ USB dongle
- Good WiFi
- A smart trainer
- Your bike
- A big fan!
Two types of smart trainers
Smart trainers fall roughly into two categories: wheel-on designs and direct-drive models.
Wheel-on smart trainers look most similar to a normal trainer, where you clamp your bike at the rear axle and then tighten a drum against your rear tire for resistance.
This design is relatively lighter (sub 40lb / 18kg), relatively cheaper (models start at £279 / $349) and relatively easier to store, as the legs often fold up.
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On the downside, wheel-on smart trainers require calibration each time you put your bike on them, which includes a 10-minute warm-up. And often, the power accuracy isn't quite as good as on a direct-drive model.
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Direct-drive smart trainers, like the Tacx Neo 2T Smart and the Elite Suito, are sturdy units that effectively replace your rear wheel. After installing a cassette, you pop off your wheel and mount the trainer on the direct-drive trainer.
Benefits of this design include stability, accurate power measurement and no need to warm-up before calibrating. The downsides? Cost and weight. Prices start at £699 / $899 and most of them weigh about 47lb / 21.3kg.
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Lastly, For those who take their indoor cycling very seriously, there is now also a wide range of smart indoor bikes. It's fair to say they cost a lot, weigh much more and take up a greater amount of space, but they do offer advantages over standard smart trainers which the dedicated indoor cyclist will appreciate.
Which smart trainer should I buy?
Good question! Our expert testers have reviewed a wide range of smart trainers and have compiled a list of the best ones on the market right now.