Instinct 2X for RowErg and SkiErg: questions

Excellent! I've weighed in on that too. Incidentally, to your question on VO2Max accuracy: I've come to the conclusion that my rowing VO2max and running VO2max are just different. They could well be, as very different muscles are involved. My rowing is north of 50 (2k time < 7:30) but my running is in the low 40's (according to Garmin). I think Garmin is very running focused, and I actually believe the VO2max. I'm not nearly as good a runner as rower, and feel the difference.

That said, I think yours is probably just too low / bad data. That's a huge difference. Give it some good hard runs and it will get more accurate. They needn't even be long.

I have Vo2 from all day activities enabled, but I don't think it does anything if you offer it better running tracks. I download data with garminconnect (python) and can see that all of the Vo2max estimates are derived from hard runs. There have been no changes in Vo2max associated with anything else.

Yeah I know that VO2max is specific to a sport so I wouldn't be surprised if my running VO2max was lower than my estimated rowing one, as I don't run at all. But that's also why I was surprised as I didn't log any cycling or running. Just curious: how do you switch off "VO2 from all day activities" ?

Sorry, I'm late to the party. I use I2X with C2PM5 via Ant-FE-C. As I'm mostly a runner, I prefer this "simple way" when I seldom row. And I think I'd prefer this if I were to plan to do structured workouts. Regarding the metrics: others were way more knowledgeable about it, than me, but I'm happy to test things if you have something in mind (if I'm capable :-D) .

Some feedback after a bit more than 1 month of usage of my Instinct 2X with my concept2 RowErg and SkiRrg.

1. I started by simply letting c2 logbook forward my workout data to Garmin Connect. This works almost flawlessly: I get accurate data for HR  (the optical sensor is often wrong, esp. when rowing, my chest strap is much better), pace, power ad stroke rate when rowing. When using the SkiErg, surprisingly, there's no stroke rate data at all (graph not there) and instead of pace there's speed (no big deal, it's more or less the same thing, but having the pace per 500m would be better, just like for rowing). Two other weird things: the HR logged by the I2X will use the optical sensor even if my chest strap is ON and connected to the I2X (ext HRM is used only when logging an activity) and while rowing does not log any step, using the Ski|Erg does log some steps (I've just switched Move IQ off but I suspect that won't make any difference). Other than that, I do get Training Effect for each session and, somehow unexpectedly, i also have a VO2 estimation (not for each session, it seems to be a weekly thing).
2. I then tried to log the activities with the I2X without connecting to the PM5: for the RowErg (activity Indoor Rowing) it's OK-ish, but the distance is zero (of course). For SkiErg I tried to used Cardio activity but that counts some steps. Using activity Indoor Rowing solved the issue.
3. Finally I tried to log activities (Indoor Rowing for both RowErg and SkiErg) on the I2X connected to the PM5: for the RowErg you get an additional grapah "distance per stroke" but surprisingly for the SkiErg you don't get any power data  (graph is there but empty) nor pace/speed data and also the distance is zero. Very weird.

Overall, I'll stick with the simpler approach: log on c2 logbook and allow it to forward to garmin connect. That's way easier to setup and provides all the important stuff. I don't see any benefit for logging on the I2X (in my case, as I log on c2 anyway).

Thanks for sharing. I'm surprised by the VO2 estimation. Are you seeing it for both RowErg and SkiErg? Is it associated with a particular kind of workout? In running you only get a VO2max estimate for a workout that has enough time at sufficiently high heart rates and (I think) can get a good perspective on the heart rate ramp up (e.g. the curve / surface of HR vs power vs time). More concretely, I see it calculating VO2Max for workouts where I either ramp up with ~4 minutes in each HR zone until some time at max effort or do intervals in zone 5. I may have one or two other workouts where it does the estimate but not enough that I am sure.

Long way of saying: I wonder if I just haven't done the right kind of workout and just need to go harder on the erg? Any insight? Thanks!

This motivated me to look at my "test piece" log ... my last one was a 5k a month before I got the watch. Hmm. I need to find some time to suffer. ;)

Hope you are enjoying the watch ...

VO2 estimation: I see it in the app (android) and online:

• App: More button (bottom bar) / Performance Stats / VO2 max: graph over 4w / 12w / 6m or current value (latest)
• Online: Reports / All activities / VO2 max: graph over 4w / 6m / 1y or current value (latest)

The values are not reported as associated to any workout/activity.

At 12w resolution in the app and 4w resolution online (weird), I see one value per week: 27 Nov, 4 / 11 / 18 / 25 Dec respectively 30 / 30 / 45 / 30 / 53.

In the app, at 4w resolution I see more points: 28 / 29 / 30 Nov, 1 / 2 / 5 / 6 / 7 / 8 / 9 / 15 / 19 / 20 / 29 / 30 / 31 respectively 40 / 36 / 33 / 38 / 30 / 41 / 43 / 30 / 45 / 49 / 30 / 52 / 30 / 53.

The dates seems more or less to match the days I've trained (e.g. the break 20-29Dec I didn't train 23-28Dec).

Huh. Don't know what to make of that! I only see entries in those VO2max reports for my running days - never erg. My plots also look very different - essentially no variation where as you see high variation. Since Sept. my VO2M has gone from 42 to 45. It goes up about .1 or .2 / week very consistently. By downloading workouts I can see the more precise (one decimal place) estimate associated with each running workout.

Garmin does advertise computation of Vo2max from "all day heart rate". It takes effect when "Smartwatch Mode is used, meaning no activities that qualify for vo2 max have been recorded in the last 30 days."

Hypothesis: My VO2MAX is only coming from running. Your watch is in all day mode (no qualifying running or biking activities). So the all day calculation is impacted by your workouts, but not exclusively. The all day method is less precise. But I'm guessing it is converging over time and getting steadily better (less variance).

I'm further guessing that you are in pretty good shape such that the 36 is way off but that the low 50's is getting to be accurate.

Out of curiosity, do you know how that estimate compares with a VO2max estimate from your best 2k time? (C2 has a table / research). IIRC it would put you in a sub 7:30 2k, but that depends on weight (IIRC).

Would be validating if they aligned!

Cheers

John

I'm gonna ask Garmin support how the VO2 is calculated in my case.

I'm a LW (72Kg) and I suck at 2K: my PB is 7:24 which according to both concept2 and rowinglevel estimates corresponds to roughly 56 VO2max.

Of my other PBs, my 5K, 10K, Half-Marathon and Full-Marathon puts my estimated VO2max at (respectively) 60, 63, 60 and 59: pretty consistent.

HornetMax said:

I'm gonna ask Garmin support how the VO2 is calculated in my case.

You do not really need to. It is described in the document My Recorded Activity Did Not Update the VO2 Max Estimate | Garmin Customer Support. If you recorded no running and no cycling with a powermeter, then the VO₂max value comes either from walking, or (more likely) from the all-day HR (most probably during the rowing). I would not rely on the value much. The estimate from the all-day HR is more or less useless.