Getting the most out of your turbo

Updated: Oct 21, 2020

As winter ramps up, now is maybe the time to invest in a turbo if you don't already have one - it's one of the most effective ways to get fit on the bike fast.

>> See my blog on what to think about if you're considering buying a turbo.

>> If you're new to turbo training then check out my Introduction to Turbo Plan

>> Or if you prefer live, coached sessions then check out Club Feel Fit with weekly, live turbo sessions via Zoom

Whilst I’m a massive fan of riding outdoors - it’s invaluable for developing skills and bike handling, as well as the mental health benefits and sheer joy of riding outside – in most cases the turbo is far more effective and time efficient at building up fitness.

- You can be onto the turbo and working hard within a few minutes, whereas a bike usually involves an element of faff finding all your gear, getting the bike ready to ride, and for most people, getting past the traffic to somewhere you can train effectively

- When training effectively you’re pushing your body hard enough (but not too hard!) that it's forced to adapt to the challenge of the training session so that it’s more able to deal with that demand the next time. And so you want to be specific about what you’re asking your body to adapt to (which energy systems you’re using) and, over time, increase the amount of time you’re spending in that zone (so that you’re always asking your body to do a little more than the time before). On the turbo you can do structured intervals where you to hold a specified power for a certain amount of time, rest, repeat, building up the time you can hold at that intensity for increasing amounts of time, whereas (for most people in the UK at least) it’s very difficult to hold constant power, given the constantly changing terrain, wind and traffic, plus the fact it’s a lot harder to follow a structured workout when you’re busy looking at the road.

- Many people have more access to data when training indoors, and this allows you to get used to what a certain effort should feel like, or for example check what your heart rate is at a certain power (if you don’t have access to power outdoors) to then apply to racing or outdoor riding.

- It’s a great equalizer – on an outdoor ride people worry about getting dropped, having an accident and mechanicals. On a turbo there’s far less barriers to entry and because a set is based on your level of fitness, Bradley Wiggins and my gran could both be doing the same session, and if I say work at 9/10 level of effort, whilst they’ll be putting out very different power, they’re both working as hard as each other, relative to their level of fitness.

- You don't need to worry about the weather!

Defining and measuring intensity

You’ll get far more out of your workouts by training at set intensities, established with regular testing. Here’s some different ways to measure what you’re doing (in order of ‘sophistication’ and cost).

1) Feel or perceived effort (RPE, or rate of perceived effort) – the most important metric but the hardest to calibrate. If I say ride at 5/10 effort for an hour you’re likely to put out far more power at the beginning when you’re fresh, than at the end when you’re tired. So if the whole session is at 5/10 effort, it should feel more like 4/10 effort at the beginning, and 6/10 by the end.

Even if you’re training by power or HR, you should still pay attention to RPE, both to check that your zones are set right, and so that you become aware of what it feels like, so that you’re able to ride in feel rather than being tied to watch screen, especially if you don’t have access to these other metrics when riding outside.

2) Cadence – cadence isn’t a measure of intensity, it’s how fast your legs are moving (in RPM, revolutions per minute). But power (how we measure intensity) is a product of torque (in simple terms, what gear you’re in or resistance is applied by the trainer) x cadence, so if you stay in the same gear/ resistance and increase leg speed then you’re working harder. If you don’t have any other metrics available then a cadence sensor is pretty cheap and it’s a good proxy for effort, and many sensor and training apps such as Zwift can then calculate that ‘virtual’ power.

Cadence is also important because we can limit risk by staying within a safe cadence range (from about 60rpm – 100 rpm, depending on the person and experience) and can work on developing our technical skill by cycling at different cadences.

3) Heart rate – Another key metric, this shows how hard your body is finding the effort, in the same way as RPE changes for the same power effort (rather than how hard you’re working), which is both an advantage and disadvantage. A disadvantage because the most efficient way to train is to keep constant power (not effort) and because it be affected by things like caffeine, sleep or stress and most significantly fatigue, so you’ll get a different reading for the same power. An advantage because it can warn you is things are off course (if your heart rate is higher than normal for the same effort, then it’s an indication something might be wrong, for example you’re getting ill or are over tired or stressed, and need to adjust your training). It’s also an advantage because a heart rate monitor (HRM) is loooot cheaper than a power meter so even for those with a smart trainer, might judge effort when outside with a HRM. Bear in mind, if training by HR a strap is usually more accurate than a watch.

4) Power – the gold standard (ish). This measures the actual power and therefore doesn’t change as you get more tired. This means you’ll go easier at the beginning of an interval so that you can finish it strong, rather than tiring half-way through. Given it’s much more precise you can follow more structured intervals which can keep the training more engaging, and builds accountability. However you need to check that power meters are calibrated (check manufacturers instructions) and be aware two metres may give very different readings so don’t rely on a turbo reading to set your power out on the road. If you thinking about buying a turbo or currently have a standard/ non smart trainer, and are thinking of investing in power, personally I would get a power metre for my bike, rather than a smart trainer, so that you can also use it outside.

Setting your training zones