By Founder and Head Coach, Matteo Cigala

As power meters are getting more affordable, more athletes are training with power than ever before. As with any training tool, power meters come with some questions – including the topic of calibration.

The calibration of the power meter is essential to have greater reliability and therefore train with the almost total certainty that the power is equal to that of previous workouts.


As far as this aspect is concerned, in some power meters, there is the automatic calibration option, but I suggest to always carry out the manual option.
At the following links, you will find how to calibrate your power meter, whether you have a Garmin or a Wahoo head unit:

Click here for WAHOO

Click here for GARMIN

Additionally, if you are using a smart trainer, it is also essential to perform a calibration. Especially important if you are racing on ZWIFT to ensure that racing is as fair as possible, for you and for your competitors.

For a smart indoor trainer, a calibration once a week, is enough, as normally the trainer is always kept in the same room under the same conditions.
However, for wheel-on smart trainer, it is always better to calibrate before each ride, or at least before each race.

Click HERE to see how to calibrate your smart trainer on ZWIFT.


Calibrating your power meter should become a regular routine because it can heavily influence the effectiveness of a training session if we decide to rely on its data.

When not calibrated, the power meter can easily be 20 watts out; underestimating or overestimating power output by that much compared to your previous work-out.

To some cyclists, those numbers may seem small. But more experienced riders will know it’s enough to ensure you’ll be training outside your training zones. This can lead to you spending time and effort inadvertently working on different metabolisms. You could be above the zones you think you’re training at and so you’ll be risking overtraining. On the other end of the scale you could end up training, maybe for a long time, with the handbrake pulled; below your required zones. And that means you’ll be training without experiencing improvements in those areas your riding is supposed to be working.


It is advisable to calibrate the power meter before each session since the time it takes to calibrate is minimal.

My recommendation is to start your cycle for 1 minute. Stop. Calibrate. And start your session.

If you are more ‘lazy’ you can avoid calibrating it in the days when you’re doing a very easy ride. On those rides, you won’t be watching your power data as closely and it’s not as important. But you should calibrate on all other days. This is especially so when the conditions you’re training in vary from day to day.

For example, during winter the bike is kept in a room where the temperature is higher compared to outside. In this situation, before setting out on your ride, I advise you to leave the bike outside for a few minutes. That way, the power meter will adjust to the outside temperature; that one you’ll be training in. Once this is done, switch to the usual calibration process from your head unit.

These are small details but it will ensure your power meter is as accurate as it can be every time and you’ll be comparing like with like data as you do your sessions over the weeks, months and years.

Matteo Cigala
Founder & Head Coach