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How To Update Your Training Zones In TrainingPeaks

August 26, 2026

Your training zones are only as good as the threshold figure sitting behind them. Test, then update, then train. Skip the middle step and every session afterwards is the wrong intensity.

Here is how to get your new numbers into TrainingPeaks, and into your Garmin so the two agree.

Before you start: get an accurate threshold

Threshold is the highest power or heart rate you could hold for about an hour. You need that number before anything below is any use.

If you have just done a 20 minute test, take your average power for the effort and multiply it by 0.95. So 250 watts becomes roughly 238. If you have not tested, you do not necessarily need to. Work it out from your recent rides here, which takes about two minutes and uses efforts you have already done.

Updating your power zones

In TrainingPeaks, click the gear icon next to your name.
Choose Settings, then Zones from the left hand menu.
Under Add activity, pick Cycling rather than leaving it as the default. If you run or swim as well, this keeps the sports separate.
Enter your Threshold Power, which is 95% of your best 20 minute effort.
In the auto calculation options, choose Coggan as the method and click Calculate.
Click Save and close.

Every future workout will now be measured against those zones.

Updating your heart rate zones

On the same Zones screen, find the heart rate section.
Enter your threshold heart rate.
Set the type to Lactate Threshold and the method to Andy Coggan.
Click Calculate, then Save and close.

What number do I use for threshold heart rate?

Ideally it is what you can hold for an hour, but almost nobody rides a maximal hour to find out. I use the average heart rate from a hard 20 minute effort instead, which gets you close enough to train off.

There is a lag at the start of any effort while your heart rate climbs, and that lag drags the 20 minute average down slightly. That is convenient rather than a problem, because it pulls the figure towards what you could actually hold for the full hour. Take it, give or take a couple of beats, and get on with training.

Match your Garmin to the same numbers

Worth doing, and frequently skipped. If your head unit is running old zones, the screen you look at while riding disagrees with the analysis you look at afterwards. In Garmin Connect, go to User Settings, then Heart Rate Zones and Power Zones, and enter the same threshold figures you just put into TrainingPeaks.

How often should I update them?

Every eight to twelve weeks in normal training, or sooner after a block that has clearly moved you on. TrainingPeaks will also prompt you when it spots an effort that suggests your threshold has gone up, which is worth paying attention to rather than dismissing.

A quick way to check without scheduling a test: run your recent rides through the FTP calculator and see whether your best 20 minute power has crept up. If you ride a club 10 mile time trial regularly, that effort is effectively a rolling threshold check without you having to do anything extra.