Suunto ZoneSense (DDFA) – thoughts after a threshold run
The multicoloured line on the chart is Suunto’s new ZoneSense from a Suunto RACE Watch. It’s a complex mathematical calculation (DDFA) based on HRV that dynamically and persistently determines your physiological state…green is aerobic, yellow is anaerobic up to the threshold, and red is over the lactate threshold (VO2max). The algorithm correlates to LT2 (LTHR), VT2 (ventilatory threshold), and LT1 (aerobic threshold).
Run Overview
Before this run, I was pretty well warmed up.
This run was probably a 97% maximal effort for me over a flat route. I had little fatigue coming into the run and was well prepared for it; I also took Maurten 100 bicarb gels, which I mentioned as they may have reduced lactate build-up. I also had a maximal caffeine dose, which raises my heart rate by 2-5 bpm.
I did a reasonable job and paced to a constant perceived effort with a consistent cadence. The graph above shows heart rate (black) and power (grey). The recorded pace and power were reasonably consistent, with a slight drop off in power/pace as I got tired. My heart rate steadily rose to about 160 bpm (0:35) and was then constant until I upped the pace toward the end (1:14). I wouldn’t be surprised if you said 160 bpm was my current lactate threshold heart rate when consuming caffeine.
ZoneSense DDFA Chart
A few thoughts come to me from Suunto’s ZoneSense curve.
- It might have an excellent link to my LTHR
- However, it seems to be at a constant level throughout the run (fair enough), but I thought DDFA was supposed to recalculate the threshold during individual workouts. Perhaps the chart software cannot colour a particular line?
- It might have been interesting if I also had SmO2 data from TrainRed or Moxy (I do have the sensors and thought about wearing one)
- There is a strange initial bump in the DDFA curve. Maybe this indicates I wasn’t as warmed up as I thought or that something else in my physiology was adjusting.
- The DDFA chart doesn’t seem to react to a marked increase in effort toward the end. I would have expected it to peak higher. DDFA is not supposed to respond to shorter efforts like that.
- I started the watch before the run to keep the 10-minute automatic calibration period out of the data. Maybe that was a mistake if it needs exercise-level RR data.
There are some interesting observations from @Brad here on DCR’s site where he finds good links between measured lactate and ZoneSense.
A similar chart from Suunto
This chart is similar; I think it comes from a Suunto employee in a half marathon race. Superficially, my effort seems shorter, more challenging and more consistent.
Take Out
I’m not sure what conclusion you can draw from my chart other than it reinforces my belief that it was a near-maximal threshold effort.
I had the same ZoneSense feedback on the watch app during the run. I frequently looked at the ZoneSense assessment but didn’t feel the need to change anything in my running.
One helpful point is that zoneSense should automatically consider factors that might otherwise affect HR – such as carried-over fatigue and caffeine use. Even the threshold values you measured two days ago in a lab could be significantly wrong with fatigue and caffeine.
Musing: perhaps this data might prove more helpful in determining training load.
I’ve used the watch app more for pacing to the lower threshold, where I’ve specifically trained to rein in my efforts on easy/long runs, keeping aerobic. It has been helpful for that.
Thoughts?
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Thanks for trying this. I’m still on the fence about zonesense. Seems like an interesting development but on the other hand it’s early days and it seems no one really knows how actionable this new data is. But I agree with you, for now at least useful to keep runs aerobic when that’s what the plan calls for.
It’s an interesting innovation and one bound to move the needle for athletes.
After using it a few times I’m still uncertain about it usefulness for me at least. I’m neither professional nor anywhere approaching elite! I have noticed though that ZS has reported different heart rates for some zones, so I will change them accordingly to see what happens.
ZS Works perfect but people needs to understand it. Traditionally people have been told that you have Zones like if that was something written in a stone, and that you can work towards moving them (simple version of it)
ZS comes to show us , what science is being telling us since years, not every day your hearth can perform the same what counts its the stress you put in the heart , and the bpm are a variable of it. each day can be different. If you are a trail runner, perhaps you can understand it better, as we run on rpe internally more than bpm, I don’t even look at pace or bpm.
The latest winner of the UTMB in an interview , describes how he used power to measure his performance in 19h , why? because its a metric that it’s constant independently of your HR and reflects if you can put the same effort hour after hour.
I have been doing 100miles races for many years, I know the UTMB course, and I am puzzled by Vincent’s comment about looking at power. He does not really say much about it, eg here: https://www.advnture.com/news/vincent-bouillard-on-gps-watch-for-winning-utmb , but I assume he must have been looking at long averages. Maybe even just an average across the whole race. Averaging over the big climbs and downhills. But in that case, the average pace gives about the same information. Thus I slightly suspect that it was a head game which worked better for him with an average power number instead of an average pace number.
He’s probably using it more to keep his power stable during long climbs, maybe helping him decide when he should jog or power walk a certain uphill segment. At least that’s the way I used power during trail races, just when climbing. On the flats I just went by feeling, when descending you go at what speed seems safe and try to minimize muscle damage.
Reading the article I feel it’s just a marketing piece, tying some behaviors with some features of the watch (eg. I look at the training load to guide my weekly effort, etc).
Well starting from the point of , what a performance. But after listening to him and seeing him run, I run with him 2 weeks ago. He , first of all , has an incredible endurance and it’s as well really really fast for very very long distances. What he said and I understood is , my HR varies too much when I look at my power I can tell that I’m putting the work that I want independent from my HR as a limiting factor. ZS allows you to do that , you HR it’s perhaps 2h in zone 5 (it happen to me) but in ZS you are in high aerobic or low anaerobic ( green yellow) means you can push and push , and it works. I would have never base on pace and HR try to go at 171-175 thinking that I can last 3h but , surprise for me , yes I can . I put my trust on it , and it seems even crazy to see that you are at 150 and in ZS in low aerobic … but it’s true , if I look at my body in barely walking in rpe
This is a very interesting take…if true.
ZS certainly appears to behave in that way, I’m not sure that my body works in the same way (it might!!!)
So we might say that ZS ignores the false LT2 from hr and power.???
Thank you for your review,
Do you have any comments on Suunto new privacy policy?
i’ve not seen it. in what respect? I know The Verge has started to include comments about Privacy Policies and the number of contracts that must be agreed to before we are allowed to use vendor’s ecosystems and products. a good idea but a bit dry.
in general the only sports tech company i vaguely trust for security and privacy is Apple and the only financial companies I trust are AMEX and my legacy UK high street bank.
as a result it’s not really important to me what suunto or coros or anyone else puts in their contracts. other than location data, I am unconcerned about the data they hold on me.
that said, I appreciate very many other people have different (and valid) concerns to me.
Thank you for your reply,
Recently, Suunto updated the privacy policy in the SuuntoApp, in summary, the users data will be shared with in liesheng group in China.
This is the discussion on Suunto forum https://forum.suunto.com/topic/11866/suunto-completely-fuse-to-china-new-agb
This is the discussion on Reddit:
https://www.reddit.com/r/Suunto/comments/1g60rie/suunto_changing_its_privacy_policy/
Thank you for your reply,
Recently, Suunto updated the privacy policy in the SuuntoApp, in summary, the users data will be shared with in liesheng group in China.
This is the discussion on Suunto forum forum.suunto. com/topic/11866/suunto-completely-fuse-to-china-new-agb
This is the discussion on Reddit:
http://www.reddit.
com/r/Suunto/comments/1g60rie/suunto_changing_its_privacy_policy/
hi
Yes: https://www.reddit.com/r/Suunto/comments/1g60rie/suunto_changing_its_privacy_policy/ seems to summarises the issues and frustrations very well.
All chinese companies, I believe, are REQUIRED to defer to the CCP when asked. The CCP will get your data if it really wants to whether it’s in Chongqing, Copenhagen, Chicago or Cornwall.
I won’t cover Huawei products in general as aspects of their organisation are deemed by my government to represent a national security threat to matters of key national infrastructure.
Me making comments like this miraculously results in a spike in hacking attemtps and some Chinese companies won’t work with me.
After the run, how well did the DDFA measured zones that show up when you press (i) next to Zones under the Analysis chart, correspond to your own experience of anaerobic and aerobic threshold? For me, ZoneSense have measured those threshold very closely to my long term experience of my zones
Lower than I think they are, lower than I feel they are, but they might be right
I need to ask what the hypothesised physiological cause is between the correlation of lt2 and the hrv calcualtions they perform.