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Accurate Recovery Time or HRM issue?

bt50
over 7 years ago
Hi,

Im doing lots of "junk" miles to get ready for a long multiday kayak trip so most days I do a 22-35 mile paddle (for a couple/few weeks) - I understand long distance everyday isn't the best for fitness improvement, but I'm doing it more for equipment testing/comfort and nutrition.

Anyway, I've been getting weird results from the HRM while kayaking see attached(this workout was done on a windy day so my heartrate and speed wasn't consistent at all if that matters). The results I get when running make perfect sense so I don't think the HRM is defective, just maybe bad connection in the sitting position? This is the first HRM I've had this issue with.

Even when the HRM results make perfect sense I'll get really short recovery time (the attached workout gave me a recovery time or 2 hours - I thought 6 hours was the min) and low training effect. Is this just from doing the same workout everyday? My calories burned daily has dropped from like 2-3k to 1-1.5k per kayaking session. I'd love it if recovery time and calories burned are correct because it means multiple sessions a day and packing less food on the trip. But I'm guessing I'm just throwing off the firstbeat algorithms by doing the same workout a lot and having other much higher intensity activities?

To maybe complicate things I'm doing most harder runs at night so my typical kayaking hr would seem pretty low to garmin connect.

Does it seem that the recovery time and calories burned is probably accurate and I'm just over (or maybe under) thinking the reults?

Thanks ciq.forums.garmin.com/.../1334052.png
  • 0 over 7 years ago
    Every metric other than time, distance (determined by GPS) and heart rate (measured using electrocardiography, e.g. a chest strap HRM, and not photoplethysmography) – and their direct derivatives such as speed (i.e. distance over time) or average heart rate – are just estimates, of which there is no practical way of ascertaining the accuracy, so it is unwise to treat the figures such as calories burned or recovery time as either gospel or objective fact.

    Every estimate is based on methodologies (implemented in technology) that makes a number of assumptions. I doubt there is a mode or activity profile on your Garmin fitness device that was designed and tested for outdoor kayaking, especially when it comes to Training Effect and Recovery Time using Firstbeat's algorithms. (I'd imagine, as with cycling, the algorithms would need data on power and not speed to determine your physical workload in kayaking to calculate VO[sub]2[/sub]max, TE, etc.)

    If you're using the running profile (or ‘app’) on your watch to record what is actually a kayaking activity, then you cannot reasonably expect aerobic TE and Recovery Time to be accurate even if the metrics are reported.
  • 0 over 7 years ago
    Interesting situation. At first glance, I would absolutely expect a workout/HR chart like the one you posted to be well north of TE 1.2 (that's barely moving the needle).

    1. TE and Recovery feedback is always contextualized based on your cardiorespiratory fitness (VO2max) and activity history. If you are in truly exceptional shape, then you'll need some pretty severe efforts to actually improve your fitness level. Your TE and Recovery feedback should be scaled to account for that.

    2. Speed shouldn't be a factor as it isn't used for anything outside of running and walking activities. There are simply too many things happening with an activity like kayaking to utilize speed as a reliable measure of external workload. That said, external workload data is absolutely necessary for VO2max detection, but certainly isn't necessary for Training Effect and Recovery Time - so not a factor here.

    3. Keep in mind that the Training Effect feedback and related Recovery Times are specifically telling you something about the impact of your activity on the development of aerobic performance capacity, which means you need to be challenging that particular aspect of your body...as a practical matter this requires some intense efforts that rev your engine. Longer lower intensity efforts provide some benefit, but not nearly the accumulated benefit as higher intensity efforts - that said, the confusing bit is from the picture you shared, it looks like there certainly should have been enough sustained intense effort to produce a higher TE.

    All things considered, does look like something fishy is going on... might be worth a visit over to www.firstbeat.com and having a chat with someone in our support team.


  • 0 over 7 years ago
    Interesting situation. At first glance, I would absolutely expect a workout/HR chart like the one you posted to be well north of TE 1.2 (that's barely moving the needle).

    1. TE and Recovery feedback is always contextualized based on your cardiorespiratory fitness (VO2max) and activity history. If you are in truly exceptional shape, then you'll need some pretty severe efforts to actually improve your fitness level. Your TE and Recovery feedback should be scaled to account for that.




    Thanks. Maybe from having done this particular course sooooo... many time maybe it's getting downgraded a good bit?

    I was wondering if maybe the HRM has a flag that it sets if the data is erroneous and sends that along and that bit of data is excluded from the calculations but being displayed. I haven't set anything manually (other than height, weight, and age) and use "other activity" for kayaking (and rowing and weights) and "running" for anything running. The attached image mostly in zone 3 was a run with a te of 3.7 and the other image was from the kayak workout I've been doing a lot (typical ranges) and got a te of 1.2. Seems odd to me!

    I was thinking the exact same course was discounted due to body/hr adaptation. Maybe I'll create a new account and see how it behaves (I have years of data w and w/o HRMs and a variety of watches so maybe it's choking on some data set?). I've been playing around with different aspects of this and if I do my typical course with say 16x500m intervals at the end my TE will still be around a 1.2-1.5, but if I break the intervals out into their own activity that activity will get a much higher TE (3-4.?). For a 30 mile paddle (in the 4+ hour range) it is showing that I'm burning about 1200 calories wearing the HRM and if I'm not wearing the HRM that number is closer to 3000.

    I don't expect the kayaking/paddling activity in garmin connect to be accurate (even talking to "high" level flatwater kayakers they estimate totally different calories, excepted vo2, power, etc...), but I was expecting different results than I'm getting based solely on my HR. Kayaking has an annoying amount of dynamic variables.

    I'm actually more interested in why the te and calories are so different from first time doing this course vs now (much slower and lower hr the first time I did this workout and the te was 4.5). I also just like seeing high TE's after a long uncomfortable workout...

    Maybe I'll create a new account and ONLY record this one activity and see what the trend does.

    Thanks!

    p.s. Maybe the result is actually accurate since at this point I probably am just "maintaining" (probably actually decreasing?) my fitness doing the same body breaking distance day after day.