Garmin

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StuH Sep 2020 1:20pm, 21 Sep 2020 3,910 posts	StuH I've certainly found the all-in-one Garmin straps to be more reliable. I think with the removable sensors, the connectors were often the point of failure due to corrosion.
larkim Sep 2020 1:26pm, 21 Sep 2020 12,012 posts	larkim (Edit - just trawled back to an older one where the value wasn't quite 292.5 divisible, so perhaps the relationship isn't quite as linear as I thought. But I'm sure someone will be able to reverse engineer it!)
StuH Sep 2020 1:35pm, 21 Sep 2020 3,911 posts	StuH Which Runalyze VO2max figure are you looking at Larkim? Standard or one of the corrected values?
larkim Sep 2020 1:41pm, 21 Sep 2020 12,013 posts	larkim Neither Stu. The "Vo2Max (by file)" values which (according to the RA developers) are read straight from the .fit files rather than calculated by the RA site iteself. You can select them to be viewed by adding them from the dataset menu. Most Garmin watches that calculate it will show it but mine doesn't, so that's the only way of seeing it (currently).
larkim Sep 2020 1:43pm, 21 Sep 2020 12,014 posts	larkim A bit more sleuthing and the algorithm seems to be divide by 1024 and multiply by 3.5 So in my case, a .fit file value of 16342 is reported on RA as 55.86. So 16342/1024 = 15.959 (rounded to 3dp), x3.5 = 55.86 (rounded to 2dp).
SPR Sep 2020 2:06pm, 21 Sep 2020 31,546 posts	SPR I know Fetch is looking at VO2 Max on file as he has a file from me. These calcs might be useful if the constants are the same for everyone.
StuH Sep 2020 2:20pm, 21 Sep 2020 3,912 posts	StuH From one activity on RA; 14106(msg79,field0) / 1024 * 3.493 = 48.12 VO2max on file
flanker Sep 2020 3:09pm, 21 Sep 2020 19,418 posts	flanker value of 12576 in 79/0, VO2Max of 43.60 from RA 12576 / 1024 * 3.5 = 42.98 Not sure the bit about RA just reporting the values in the fit files tallies with this field, as they'd have to do some sort of manipulation to get from the large number to the VO2Max
SPR Sep 2020 3:11pm, 21 Sep 2020 31,548 posts	SPR There RA VO2 Max and there's VO2 Max from file. You probably haven't got VO2 max from file showing.
larkim Sep 2020 3:51pm, 21 Sep 2020 12,017 posts	larkim Some interesting outliers there. Stu - what is the value that RA would report? Mine were bob on - except for one entry from a few years ago which was out by a similar margin to flanker's one above. The / 1024 * 3.5 conversions I've got from the code for fit4ruby which is github. Wonder if there is any more nuance to the calculation. RA do "just " report the values, but from a thread I participated in with their devs a while back they grabbed the calculation from another helper. For just about all of the raw fields in a .fit file there is some calculation required (e.g. converting time stamps to dates) so having a conversion factor that goes from 16105 to 55.1 wouldn't be unusual.