Tuesday, 21 November 2017 12:19

Training Aids: What They Are and Why You Need Them

Feel on the bike is important, but it only goes so far. Getting data back from your ride is critical to training effectively, and beyond that it’s just nice to know how fast you’re going and how hard you’re working.

What is a training aid? Essentially any piece of technology that gives you information about your ride without itself making you faster. Sure, using them effectively can make you much faster, but it still requires you to do the work, unlike a set of aero wheels or a lightweight frame. The market is full of training aids, from sunglasses that tell you how fast to ride to devices giving you real time, in-depth pedal analysis. Here, however, we divide them into three main camps: head units, watches and power meters.


A head unit is a must for real time feedback on the bike, and most cyclists nowadays don’t leave the front door without one. Basic designs, just showing speed and distance, can be picked up very cheaply, but much more advanced, GPS-enabled units have become de rigeur in recent years. Garmin lead the market on this and arguably still do. Lezyne, Wahoo, and a few others have upped the competition recently, however.

What makes a good head unit? GPS features, a good screen and interconnectivity, in a word. There are dozens of products on the market that tick these boxes and so much of your choice comes down to personal preference and budget. Here, however, are some of the best:

Garmin have more cycling computers on offer than you could shake a stick at. Possibly the most popular is the Edge 520. With a 58mm display, it’s more compact than its upmarket cousins but offers many of the same features, most notably live Strava tracking. It can be connected to Garmin’s own lights, cameras and even, thanks to the latest generation of Shimano Di2, your derailleurs.

The Edge 820, meanwhile, is the goldilocks of the range. The same size as the 520, but twice the price, it offers almost all the features of the top-line models in a smaller package. It has all the connectivity you could want—ANT+ and Bluetooth—and can create routes for you to follow, offering the choice of bike paths or roads. Unlike the 520, it is touchscreen.

The Edge 1030 is Garmin’s latest and greatest head unit, offering quite the package. Its 89mm screen makes it look like a small smartphone, with a touch screen and display quality to match. It can link to your phone too, allowing you to send riding mates pre-composed messages from the saddle—something no Garmin has been able to do until now. Route planning is the best Garmin have thanks to the new Trendline Popularity feature. Essentially this takes other riders’ routes into account when planning yours, making it easier to plan the best possible route, not just the fastest one. The 1030 also boasts a massive battery life, plus the option of an external power pack.

Garmin used to have the head unit market to themselves, and they still dominate it. The Wahoo Elemnt Bolt (yes, missing the third ‘e’) has recently emerged as a direct competitor to the Garmin 520. The two are very similar in size and features, though the Bolt is somewhat more rugged, with a black and white screen that looks cheaper but is easier to read in varying light conditions. The Bolt’s trump card, however, is that you can programme everything directly from your phone. User friendly, practical and (supposedly) more aerodynamic than anything else out there, the Elemnt Bolt has brought some welcome competition to the market place.

Wahoo also offer their standard Elemnt, which sits somewhere between the Elemnt Bolt and Garmin Edge 820. Again, everything is customisable from a smart phone, and usability is king.

Lezyne also have a range of GPS head units to match their excellent tools and lights, with the Enhanced Super GPS topping the range. Cheaper than either the Elemnt Bolt or Edge 520, it offers most of the same functions whilst carrying a little more bulk. Lezyne use a smartphone app to input routes into the head unit, and you can easily change destination mid-ride. The Enhanced Super GPS can also run for up to 24 hours.


Head units are excellent for use on the bike, but not much else. If you’re a multi-sport athlete, or just want something more versatile, there is a multitude of watches to choose from. Though less elegant than a head unit, a sports watch strapped to your handlebars can work just as well.

Leading the market for serious athletes is the Polar V800. It offers GPS tracking but not mapping and is intended solely as a training aid and activity tracker. With its extremely precise heart rate monitor, the V800 can accurately map your training load and recovery time. Polar have included an orthostatic test (see our Recovery blog post ) as standard, as well as a progressive ‘fitness test’ that tracks improvement over time. Each session’s data can be automatically uploaded to TrainingPeaks and similar services, giving an in-depth picture of your training over days, months or even years. As you get used to the watch, tracking data becomes second nature.

Watches are normally aimed at triathletes or runners. As such there are myriad brands and options to choose from, though again, Garmin lead the way when it comes to GPS. Suunto too produce excellent multi-sport products, and tech giants Apple and Samsung are constantly working to refine their models to suit the athlete’s needs.


A power meter is perhaps the ultimate training aid. Knowing your exact power output regardless of gradient, wind, other riders or anything else is fundamental to any serious training programme (for more on that see our training blog). Power meters work by measuring the force of each pedal stroke with a strain gauge, then multiply this number by the cadence to give a reading in Watts. The strain gauges can be mounted in any number of places depending on the brand: crank arms, pedals, axle and elsewhere.

The SRM power meter has been around for a long time and remains the gold standard when it comes to consistency. The German company produces its own head units too, though these aren’t quite as up to date as the latest kit from Garmin and Wahoo. An SRM will, however, pair with any ANT+ enabled device. Due to the delicacy of strain gauges many power meters produce warped results when exposed to big variations in temperature, especially extreme cold. SRM lead the bunch here, giving consistent data no matter the conditions. This, combined with excellent battery life, makes for perhaps the most reliable power meter on the market.

PowerTap have also been in the game for quite some time. Their G3 measures power at the rear hub, offering highly accurate data with very little weight penalty; the G3 can weigh as little as 56g more than a normal, high-quality rear hub. Installation, meanwhile, couldn’t be easier. PowerTap can sell the G3 pre-laced into a choice of rims, so all you need to do is change your cassette. The P1s, meanwhile, are a pedal-based system. Installation is a trump card here too, since they can be moved about between bikes with minimum fuss or planning.

Power meters used to cost as much as, or even more than, a top-end groupset. Prices trickled down as the technology became more widespread but it was Stages who lit the touch paper of a pricing battle that has raged ever since. Good news for the consumer. Stages’ power meters are joined to the left-hand crank, with an option for just about every crank you can think of, and are amongst the lightest on the market. Their Shimano 105 option became the first ever ‘cheap’ power meter when released several years ago, though prices vary considerably depending on which crank you choose. Stages’ simplicity is limiting, however. Only having strain gauges on the left side, they take the power reading for your left leg and double it, assuming you are perfectly balanced specimen when in fact few of us are. Still, these power meters are reliable, tough and practical. Team Sky’s choice.

Quarq are a subsidiary of SRAM—perhaps the most innovative component manufacturer in cycling (there’s a reason so many of our clients choose SRAM Red Etap for their Dassi Interceptor). Quarq have really stepped up their game in recent years. Their latest power meters, the DZero and DFour are SRAM and Shimano compatible respectively, boasting a range of innovative features. Like many manufacturers, Quarq do not measure power for both legs, but nevertheless manage to get independent left-right readings. They do this by measuring power across the whole pedal stroke, then calculate how much is being produced by either leg by taking the position of each crank into account. The final reading is very accurate and deals with temperature change excellently.

Keen to dominate the market, Garmin produce a power meter too. The Vector 3 pedals, now in their third generation as the name would suggest are a marked improvement on anything Garmin have produced before. The previous models came in two pieces: the pedal and a ‘pod’ housing the strain gauges, which sat between the pedal axle and crank arm. Because of the design, they had to be torqued very precisely, making installation tricky and essentially undoing one of the Vector’s main selling points. Now, however, the pods are gone and the vector looks very similar to a normal pedal. Switching between bikes couldn’t be easier. When combined with a Garmin head unit, moreover, the Vector 3s unlock a host of features to give you extremely in-depth power readings. Altogether a neat, practical, high quality offering.

4iiii (pronounced ‘four-eye’) are a Canadian company who pride themselves on customer service and accessibility, though their products are still cutting edge. Their Precision unit weights just 9g and is attached to your left-arm crank. 4iiii can attach this for you if you ship your crank to them, or alternatively can pre-install it to a crank of your choice. The Precision Pro is the same deal, except installed to both the chainset and left crank, giving power readings for both legs. Both units are extremely accurate—all the more impressive for their ‘entry-level’ price. In January 4iiii are releasing their newest model, the Precision Podiiiium.

We’ve only just grazed the surface when it comes to power meters. Power2Max bring the best of German engineering to the table, with their products designed for Team Movistar. Rotor, meanwhile, produce a range of power meters to accompany their famous chainrings and brand new UNO groupset. Shimano too have a power meter to accompany their newest groupset. Anticipated for a long time, it has only just hit the shelves. On the other end of the spectrum to this Japanese giant, Watteam have recently released a cheap, high-quality system that curiously requires home installation.

Training with power is by far the most efficient way to improve. Because of this, more and more manufacturers are coming to the table, forcing prices down and quality up. Good news for all concerned, really.

To conclude, then, we’re spoilt for choice when deciding how to track and record our rides. Big data is becoming increasingly popular in all sports, and the technology to collect this is available to the masses, not just elite professionals. Where next? Real-time feedback on your drag coefficient? A head unit that tells you when to attack and when to stay in the bunch? What do you think?

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