The advent of smart turbo trainers and new software means indoor training has undergone a bit of a revival in recent years, gone are the days of staring at a wall in your basement spinning aimlessly; now we are flush with options to guide you through highly targeted workouts and even video games that will keep you entertained as you suffer. So popular has riding indoors become, the UCI has introduced an e-sports world championships.
The rise of applications like Zwift, TrainerRoad, The Sufferfest and so many others, has also heralded the dramatic rise of the smart trainer. Using a Bluetooth Smart or ANT+ connection, a smart trainer will not only use a built-in power meter to measure your output, but can also change the resistance to help you get the most out intervals or simulate virtual changes in topography and road surface. At the pinnacle of the category, smart trainers can simulate rough surfaces, climbs and descents while to truly replicate the on-road feel.
Wheel-on smart trainers
Wahoo Kickr Snap
One of the most user-friendly in the category
Flywheel weight: 10.5lbs / 4.76kg | Connectivity: ANT+, ANT+ FE-C, and Bluetooth Smart | Accuracy: +/- 3-percent | Max power: 1500-watts | Max simulated grade: 12-percent | Price: $599 / £499 / AU$649
While Wahoo's Kickr direct drive trainers are likely some of the first that comes to mind (for good reason), the brand's wheel-on Kickr Snap is no chump.
With both ANT+ and Bluetooth connectivity, Wahoo makes the unit compatible with basically every training app under the sun and the Snap plays nice with iOS, Android, Windows and Mac.
At +/-3 per cent accuracy, the power measurement of the V2 edges in just above much of the competition and in the ERG mode, the Snap adjusts the resistance at the rear wheel to match what your app of choice dictates.
The frame is sturdy and doesn't feel as though you're going to tip over when the intervals get tough, but the legs are foldable for easy storage.
Kurt Kinetic Rock and Roll Control
A smart trainer that simulates outdoor riding
Flywheel weight: 12lb / 5.4kg | Connectivity: ANT+ FE-C and Bluetooth | Accuracy: +/-3-percent | Max power: 1800-watts | Max simulated grade: 10-percent | Price: $749 / £750 / AU$134
Kurt Kinetic's Rock and Roll trainer offers an indoor riding experience that many attempt to replicate with a rocker plate. The unique frame sways from side to side, forcing you to engage your core as you would in the real world. On the downside, if space is at a premium, the Rock and Roll has a massive footprint and does not fold down.
Now, Kinetic is offering the Rock and Roll trainer with a Power Control unit which features a 12lb flywheel and app-controlled interactive resistance. Even better, if you've already got a Rock and Roll, or any other Kurt Kinetic trainer you can upgrade it with the Power Control Unit.
The Kurt Kinetic Rock and Roll Control has a maximum resistance of 1800-watts and maximum simulated incline of 10-per cent. There is plenty of leg burning power on tap.
Tacx Flow Smart
A budget-friendly smart trainer for indoor training newbies
Flywheel weight: 1.6kg | Connectivity: ANT+FC-C, Bluetooth Smart | Accuracy: +/-5-percent | Max power: 800-watts | Max simulated grade: 6-percent | Price: $396 / £199 / AU$TBC
Not all smart trainers have to be expensive, and the Tacx Flow smart is one of the most budget-friendly trainers out there. Using electromagnetic resistance, the Flow Smart provides interactive resistance from the training app of your choice or the brand's own proprietary training app.
For apartment dwellers, the folding legs make for compact storage, and the elastogel core roller helps to dampen noise and vibrations, and limit the passive-aggressive notes your downstairs neighbour slides under your door.
While the Flow Smart doesn't offer quite the level of resistance, simulated grade or power accuracy as some of the more expensive units, it's also only a little more than half the price. For someone looking to get into indoor training, the Tacx Flow Smart is a great starting point.
Mid-range tyre driven trainer with good power accuracy
Flywheel weight: 2.6lbs / 1.2kg | Connectivity: ANT+ FE-C, Bluetooth | Accuracy: +/-5-percent | Max power: 1500-watts | Max simulated grade: 15-percent | Price: $599 / £500/ AU$749
Coming from the same umbrella company that brought you PowerTap is the CycleOps M2 (formerly the Magnus), which offers good power accuracy through its electromagnetically controlled resistance unit.
With 1500-watts of resistance and 15-per cent simulated grade, there is plenty to push up against as you race up Zwift's Epic KOM mountain or chase down breakaways with Sufferlandrian Director Sportif Gunter Von Agony telling you to ride faster.
When it comes to connecting your bike to the trainer, the M2 has three quick settings for typical hub spacing on both road and mountain bikes, and a two-inch roller for up to a two-inch tyre in 650b, 700c, 26in, 27in, and 29er.
BKool Smart Pro II
Unique mid-range wheel on trainer
Flywheel weight: N/A | Connectivity: ANT+ FE-C, Bluetooth Smart | Accuracy: N/A | Max power: 1200-watts | Max simulated grade: 20-percent | Price: $589 / £499 / AU$899
Spanish outfit BKool’s Smart Pro II doesn't look like any other smart trainer on the market. The resistance unit is reminiscent of a giant tennis ball which has been chopped in half and the pressure on the rear tire is regulated by your body weight rather than a tension knob or lever— though others have used this method in the past.
While the resistance unit might appear to be bright and friendly, it can deliver a leg-burning 1200-watts of resistance and simulate up to a 20-per cent grade. BKool has also upgraded the Smart Pro’s resistance unit to offer smoother transitions between gradients and make less noise.
With both ANT+ and Bluetooth connectivity, it’s compatible with the brand’s own training app (and comes with a 12-month premium membership) as well as Zwift, TrainerRoad and The Sufferfest too. However, be warned if your bike uses a rear thru-axle, you’ll need to purchase an adaptor.
Direct drive smart trainers
Wahoo Kickr Core
Compact and quiet direct drive trainer
Flywheel weight: 12lbs / 5.4kg | Connectivity: ANT+, ANT+ FE-C, and Bluetooth | Accuracy: +/- 2-percent | Max power: 1800-watts | Max simulated grade: 16-percent | Price: $899 / £699 / AU$1199
Wahoo's Kickr Core sits in the just under the brand's flagship direct-drive Kickr model. It's a few hundred dollars cheaper, and the main differences are the lack of folding legs, height adjustment, the slightly smaller flywheel at 12lbs / 5.4kg (the same size as the 2016 and 2017 Kickr), and you’ll have to supply your own cassette.
What the Kickr does offer is universal training app compatibility, 1800-watts of electromagnetic resistance, a simulated grade topping out at 16-percent and claims of a +/- 2-per cent power accuracy. Once you've installed your cassette, it works with quick release, and thru-axle rear ends and offers smooth transitions in resistance and a surprisingly realistic road feel.
Should you want to take your indoor riding to another level still, it’ll work with the Kickr Climb and Kickr headwind too.
Kurt Kinetic R1
Direct drive trainer with rock and roll feature
Flywheel weight: 30.9lbs / 14kg | Connectivity: ANT+ FE-C, Bluetooth, USB | Accuracy: +/- 3-percent | Max power: 2000-watts | Max simulated grade: 20-percent | Price: $1050 / £999 / AU$1699
The first lime green direct drive trainer from Minnesota-based Kurt Kinetic; the R1 combines the features you'd look for in a direct drive trainer smart trainer with a bit of rock and roll flavour. It’ll work with several axle standards and cassette, offers interactive resistance from your favourite training app, but then you also get about 15-degrees of side to side sway to keep your core engaged.
With a sizable 30.9lbs / 14kg flywheel, the R1 claims a power accuracy of +/- 3-per cent accuracy, offers 2000-watts of resistance and maximum slope simulation of 20-per cent. Swapping the freehub also requires no tools, and the R1 will accept Shimano and SRAM cassettes with a replacement freehub required for SRAM XD and Campagnolo.
The trainer requires a wide stance to prevent you from tipping over, the legs fold away for compact storage, and there is even a handle to help you move it around your house.
Tacx Neo Smart 2
For the dedicated Zwift lover, if you can afford it
Flywheel weight: 125kg / 275.8lbs (virtual) | Connectivity: ANT+ FE-C, Bluetooth | Accuracy: +/- 1-percent | Max power: 2200-watts | Max simulated grade: 25-percent | Price: $1,399 / £1,199 / AU$1,899
If your pockets are deep enough, the Tacx Neo smart trainer is a Zwift or Rouvy lover’s best indoor companion. Offering a degree or two of movement in the freewheel the Neo 2 can also recreate road surface sensations with some clever electronics.
Instead of using a belt to spin the freewheel like most other direct drive trainers too, the freehub Neo Smart 2 turns the flywheel, which Tacx says allows the trainer to offer +/- 1-per cent power accuracy without calibration—Tacx is so sure if this, they don’t even provide an option to calibrate. The Neo Smart 2 also offers advanced power metrics like left/right balance.
Using electromagnetic resistance, Tacx says it can simulate up to a 125kg flywheel and offers 2200-watts to fight against and a max incline of 24-per cent.
Great for those with big engines
Flywheel weight: 20lbs / 9kg | Connectivity: ANT+ FE-C, Bluetooth | Accuracy: +/- 2-percent | Max power: 2000-watts | Max simulated grade: 20-percent | Price: $1199 / £1000 / AU$1699
With a substantial 20lb flywheel to drive, the H2 combines real-world inertia with electromagnetic resistance to offer 2000-watts of interactive resistance from your favourite training app.
The H2 sees integrated speed and cadence (and of course power) sensors and offers smooth transitions in power. Further, CycleOps tests each unit using a PowerTap before it leaves the factory to ensure accuracy.
The legs fold away, and there’s and carry handle, so you don’t throw out your back trying to move the hefty trainer. It comes with end caps to suit most modern rear ends (bar Superboost).
Elite Drivo II
Trainer for the data nerds
Flywheel weight: 13.2lbs / 6kg | Connectivity: ANT+, Bluetooth Smart | Accuracy: +/- 0.5-percent | Max power: 2300-watts | Max simulated grade: 24-percent | Price: $1199 / £1199 / AU$1599
Elites Drivo II takes power seriously, with an accuracy claimed to be within +/- 0.5-per cent. The Italian outfit says the built-in Optical Torque Sensor takes measurements from 24-points and can even measure the smoothness and roundness of your pedal stroke.
With 2300-watts of resistance, up to a 24-per cent simulated grade, the Drivo features built-in speed and cadence sensors too. It does require a bit of assembly out of the box, and the fold-out legs provide for a stable pedalling platform and essential caveat if you’re trying to crawl up a 24-per cent virtual incline.
The trainer plays nice with a host of third-party training apps, and the trainer comes with a 36-month membership to Elite's My E-Training app.
What to look for in a smart trainer
There are two types of smart trainers these days, wheel-on/tyre driven and direct drive. Just as the names suggest, wheel-on places a roller against your rear tyre to provide resistance while direct-drive uses a cassette connects directly to your bike and is wheel-off.
The most significant factor in determining which smart trainer is best for you will be how much you're willing to spend, with the wheel-on variety being more budget-friendly.
Of course, there is a trade-off, however. The wheel-on trainers are usually louder and don’t offer the same accurate power measurement their direct drive cousins do and most direct drive trainers require power calibration before each use, generally in the form of a 'spin down.'
There are of course still 'dumb' trainers which have no electronics which these can be used with most training apps provided you have a power meter or speed and cadence sensors for virtual power. With these, however, you miss out on the interactivity, and as they can't take commands from apps like Zwift and Rouvy they also lose a bit of their entertainment value.
Smart trainers can also offer ERG mode where the trainer will tailor the resistance curve to help you hit your target power. For example, let's say you're riding using TrainerRoad and your target power is 200 watts, ERG mode will provide the right resistance for 200 watts regardless of whether you're pedalling at 60RPM or 150RPM.
This means you can focus more on the pedalling and less about shifting, cross chaining and blowing your interval because you got a bit too involved in whatever you were watching on Netflix.
When it comes to communication with your device, almost every trainer can connect via Bluetooth Smart or ANT+ and now, ANT+ FEC. While Bluetooth Smart has been able to broadcast data and control your trainer from the outset, ANT+ only transmits data and ANT+ FEC allows for your device or training app to send orders to the trainer.
As of around 2016, virtually every trainer on the market was dual-band, meaning they worked on both protocols, so no matter if you're using a Garmin head unit or your laptop, your smart trainer should be able to speak the right language.
Bikes use a variety of axle and free-hub standards these days it's also essential to make sure you've got the right adaptors. Most direct-drive trainers come with a variety of end caps to suit multiple axles; however, wheel on trainers may require a special axle, either one from the respective trainer company or a third-party universal option from The Robert Axle Project.