Forget about phone HRV apps. There is no need to invest a 1000 $ for the top of the line Garmin Fenix 6X pro solar with chest strap. I bought my girlfriend a much cheaper Garmin Venu for 150 $ without chest strap and it has almost the same capabilities and software as its bigger brother. Including an oximeter and alarm function in case of a fall. And if you are consistently wearing and using it the software knows for years how you trained and how you slept. No need for manual input. And if you are not prepared to invest in such a technology then why did invest in the Mountain Training Group a bigger amount? The UH site and the 7-hour video tutorial will give you more info to start with. And the coaches can not help you if your metrics is wrong.

I have been using for 20 years top-of-the-line Suunto watches and I miss the real-time EPOC calculation on which the Training Effect is based. But Garmin is superior in regard to software integration. Both use in the background the Fisrtbeat algorithms for HRV analysis developed by a Finnish institute. Hope my advice helps!

For those interested in how the most advanced technology works I suggest looking at the Fistbeat page here: https://www.firstbeatanalytics.com/en/features/ This is what good wrist-top computers like Garmin and Suunto are using. I strongly doubt that other smartwatches more inclined in transferring the phone to the wrist are paying to the Fisrstbeat, who are developing the technology in the past over 30 years. Probably some 20 years ago I purchased the Firstbeat Athlete software which uses EPOC (Excess Post Exercise Oxygen Consumption) as the main metric for the aerobic load. It was good software because it suggested what training should I do in order to improve my aerobics without overtraining. Training peaks go one step further with their hrTSS. They multiply the load by the duration, something that EPOC sortwares does not do. In EPOC-based metrics, a 30 min HIIT training on an elliptical would give me a higher value than a multi-hour ascent in Zone 2. Which is not true of course. Thanks Chantelle for linking the Scot’s post about modifications to the hrTSS depending on e.g. the backpack load. However, in my humble opinion, this is not entirely correct. Higher backpack load results in exertion which will be reflected in both HR and HRV. The steepness of the climb, which can be derived from the GPS and barometric data and again should be reflected in your HR and HRV data. The problem with the TP is that they do not use HRV directly in any way, which is a step backward. So, I would suggest, use the TP to monitor load but also look at what your Garmin is telling you about sleep quality, the necessary time for recovery, etc. Third-party software, which was commented on in Steve’s post is not that reliable, I agree with that. But just look at the source, in the Garmin or Suunto watch which is backed by over 30 years of science and research in the Firstbeat company and institute.