Suunto 3 Fitness: Firstbeat Features, Explained by Firstbeat

The special fitness features of the Suunto 3 Fitness – adaptive training guidance, rest-recovery “Resources” measurement and sleep quality assessment – use technology coming from Firstbeat.

Firstbeat is quite interesting.Extremely interesting for someone into sports technology, in fact: It is a rather small Finnish company founded in 2002, specializing in “heartbeat analytics,” as their homepage’s tagline states. From there, they have gone on to become “the leading provider of physiological analytics for sports and well-being.

The technology is particularly interesting as it uses something as (seemingly) simple as one’s heartbeat to derive quite a lot of data from that. Scientific as it all is, or certainly sounds, there also tend to be questions around it. I sure wanted to know more…

To that end, I (GZS) spoke with Herman Bonner (HB), communications specialist for Firstbeat:

GZS: Training guidance on the S3F uses the Firstbeat “Cardio”/improving program; there’d also be a “maintaining” and “highly improving” plan.

So, it’s squarely aimed at people – as described in the marketing – who do not yet have too good a VO2max (taken as *the* measure of fitness), but want to improve it, softly. Correct?

HB: Yes, the adaptive training guidance offered by the Suunto 3 Fitness is designed with the assumption that you want to improve your cardiorespiratory fitness (aka aerobic fitness, or aerobic performance capacity), which is measurable in terms of VO2max. In other words, the maximum rate at which your body can utilize oxygen as the catalyst to transform nutrients into energy.

It is possible to prescribe training activities targeting the maintenance of your current fitness level, or to target a more rapid improvement in cardiorespiratory fitness. For the sake of simplicity, which feedback from the market supports as a ‘good idea’ – offering a simple, safe path towards improving your fitness is the easiest solution.

Naturally, there’s nothing stopping anyone from exceeding the recommendations and pushing themselves harder.

That said, there’s a well-known phenomenon of folks going hard early on in a training program, exhausting themselves and losing motivation to continue as a result.

So, if you’re going to offer guidance with the goal of creating lasting behavioral change, then it’s essential to help people challenge themselves at the right level.

Of course, to do that you also need to know something about a person’s current fitness and activity levels, which is why the introduction of VO2max detection unlocks such valuable insight for personalized training guidance.

GZS: Corollary is that people who are already athletes (or at least have such a person’s VO2max) will – as I’ve seen – not profit (as much, if at all) from that training guidance?

HB: When it comes to cardiorespiratory fitness, like most other aspects of life, the better you already are, the harder you need to challenge yourself to improve.

The lower your VO2max is when you start following the adaptive training program, the easier and more likely it will be to experience significant gains.

So, for example, a 27 year old male with, say, a relatively low VO2max of 38 might get to 42 more easily than someone with a VO2max of 52 could get to 56. So, that’s an underlying point behind that and a sort of benefit.

In a way your question almost answers itself. Because it’s a program designed to improve your fitness, the people who have the most room for improvement have the most to gain.

Of course, there are limits built into the programming, for example, the fact that the program will offer you a maximum 3-4 workouts per week. If you’re really into endurance sports, training for a marathon, triathlon or something like that, then you’re probably already exceeding the parameters of the program.

GZS: The problem for high-VO2max/fitness level people is that the plan recommends (only) high exertion sessions; it begs the question: What are Firstbeat’s “philosophical” and practical backgrounds for training planning? (I.e., you don’t seem to be fans of 80/20 Running for improving endurance but to follow an approach closer to HIIT)

HB: This is a good question, and it might be worth cracking into the constitution of a “Firstbeat Training Philosophy” at some point.

Although, it’s probably better described as a system of applying training principles using physiological data. So, for example, if you want to improve your aerobic performance capacity, you need to challenge yourself.

Now, if your goal is succeeding in a race of some specific type, then naturally you need to incorporate the elements of the relevant training programs for those events.

A program designed to improve your cardiorespiratory fitness won’t automatically prepare you to run a marathon, race 800 meters, or play basketball. Those require additional training focused on the fundamental elements of those activities.

Long slow runs can be an important part of your training program, but they don’t have the greatest impact on improving your cardiorespiratory fitness, at least from an efficiency perspective.

It takes a much, much longer time to create the same amount of homeostasis disturbance from slow runs compared to more intense efforts – which goes a long way towards explaining the popularity of HIIT these days.

GZS: Re. the “Resources”… This feels a lot like e.g. the “Readiness” score some Garmin devices give at the beginning of a training session, but it isn’t quite the same – the S3F measures “Resources / Stress-Recovery” throughout the day (with 24/7 HR tracking turned on, of course), right?

HB: Interesting connection you’ve drawn there. I suppose there’s some similarity in the presentation, but the underpinnings are remarkably different and unrelated.

I think the Garmin feature you mention is the “Performance Condition” feedback which is actually quite closely related to the VO2max calculation, in that it’s comparing internal (HR-derived intensity levels) with external (running/walking speed, or watts from a power meter for cyclists) workloads, and comparing that analysis with your historical baselines.

The Resources display is essentially revealing an offsetting comparison between the presence and magnitude of sympathetic and parasympathetic activation within your autonomic nervous system.

Physical activity and stress responses (sympathetic dominant activity, fight-or-flight) deplete your body’s resources, while rest, recovery, sleep – especially sleep – (parasympathetic dominant activity, rest-and-digest) replenish your body’s resources.

GZS: That also means that I get a running score for this all throughout the day, but what is that score built on / representing?

I’m currently explaining it – to myself – as HRV, with low variability meaning sympathetic nervous system is more active, body is stressed, whereas higher HRV = parasympathetic nervous system is active, “resources” are building up… but is that how/what it is?

HB: That’s a good way to think about it. It’s a bit like a bank account, with deposits and withdrawals, or a battery that charges and drains.

GZS: And what is the (best) use of this, really? Does it reflect recovery/restedness, really, or just activity, or maybe even biorhythm?

HB: I’d suggest that the feedback has a handful of particularly helpful applications.

From a training perspective, performing physical activity when your body has the resources it needs to adequately support your efforts opens the door for getting the most out of your effort – this is especially true of strenuous efforts.

It’s not just about being able to gut through and survive the effort, but your body’s ability to respond positively, bounce back, and adapt as a result of your exertions to better prepare you for the next similar challenge.

There are, of course, great applications for this type of feedback in daily life as well.

You can assess the ability of your overnight recovery to support your daily needs. You may be able to see and understand how different routines and schedules impact your body’s ability to cope. I’ve heard numerous examples of folks catching the impact of illnesses and treatment in this particular type of feedback.

GZS: And what does it tell me if I never seem to get above a 48% score?

HB: Without trying to be coy, interpreting that type of feedback is a little difficult without knowing what you’re actually doing.

GZS: The third Firstbeat feature in the S3F is sleep quality assessment… and in that, it’s not just the “deep sleep” = I didn’t move, that other watches show, but it’s also based on an HRV measurement, throughout the night, is it?

HB: Yes, feedback on your sleep quality is a product of a combination of movement and HRV-measurement data.

Historically, sleep data from wearables hasn’t been particularly informative. This is largely because, for the most part, devices have relied exclusively on accelerometer/movement data – which doesn’t necessarily say anything about the restorative quality of your sleep.

In an extreme example, you’ll see cases where someone consumes a large amount of alcohol and lies down to sleep. They may move very little – if at all.

From a movement perspective it may look like deep sleep, which is associated with excellent quality. If you look at the physiological data, you’ll see a significant reduction in the restorative power of sleep after alcohol consumption.

Here’s a recent article on precisely this: (Disclosure: the data and some of the contributors are from Firstbeat).

There are a great many things that impact sleep quality, including diet, timing of physical activities, natural dispensations… etc.

GZS: Does the sleep quality assessment work similarly to the “resources” measurement, then? In which way?

HB: Yes, it’s essentially the same information, but segmented and reported separately. This makes a lot of sense if you think about the massive role sleep plays in physiological recovery and adaptation.

Logically, the ability to look at sleep quality for recovery insight is the same as looking at workout for physiological impact.

Yes, there are constant ups and downs throughout the day and night, but these are the big events where you might want to take an extra look.

That’s it for this deep dive into the Firstbeat functions on the Suunto 3 Fitness. I’m currently testing the “Lifestyle Assessment” from Firstbeat, which is similar to the “Resources” measurement in a way, but goes quite beyond that.

I’m already curious, but we’ll have to wait and see what comes of it all.

Time for another, public, Thank you! to Herman Bonner / Firstbeat for the information!

More on the Suunto 3 Fitness’ Firstbeat features here; more about the watch on Suunto’s website here.

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  1. Anonymous

    Hi Gerald
    Did he say something about periodization in the adaptive training guidance ?


    • I have been told that it exists (or should exist)… Wanted to have a closer look at the suggestions, but they don’t work too well for my high VO2 max 😉

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