Running SmO2 from BSXinsight with STRYD power !? Prep for North London HM

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Power Run SmO2 HR BSX Insight STRYD 920XT V800
Yellow=Power, Teal=SmO2, Red= HR with dropouts

This image was from last night’s ‘fun’ run. What you are looking at is power, HR and muscle oxygen (SmO2) – from running. Not the most promising of graphs admittedly!

Purpose: I’m tapering, the taper requires a few short HM paced intervals. Also I am testing out weird combinations of kit. Just because they were there to be tested (and I might use this kit combo in this weekend’s North London Half Marathon).

Session: Straight into easy pace – slower than 5:00/km then 4x 40 second intervals at 4:00/km with 2 minutes 20 easy pace recovery. The stops were for very brief  periods going through gates.

Execution: the slow pace was a bit slower than planned and the fast was a bit faster than planned. There or thereabouts.

Kit: STRYD paired with Polar V800 in cycle mode showing running power and HR. Garmin 920XT paired with BSX Insight. 920XT showing SmO2 and tHb.The BSX recording SmO2 and tHb. Garmin not showing proper instant pace as the BSX takes the footpod channel grrrrrrrr!. (I could have used the Suunto for the power running, that would have been fine but the Suunto isn’t ANT+ so it can’t talk to the BSX)

Challenge: Knitting it all together.

The data merging challenge here was tricky. Originally I’d hoped to get it into SportTracks but that has proved difficult without a FIT file source. The data I had was .HRM from the Polar and .CSV from BSX.

At present no Garmin device will RECORD SmO2/tHb into a FIT file (May 2016? Q1 officially). So I used Golden Cheetah. That read and merged the .hrm and .csv files easily enough. I was then unable to export FIT format from Golden Cheetah (eg to SportTracks).

BSX recorded the tHb and SmO2 well enough BUT the subsequent export to CSV currently only exports SmO2 so I was left missing tHb.

Hopefully that process is clear to everyone ! (As mud)

Well, I thought it was quite neat to compare muscle oxygen data and running power. A bit of a technical challenge to do it. Now all I have to do is understand it.

I suspect with indoor cycling it will be an easier technical challenge as I believe that Golden Cheetah will record live data with an ANT+ stick and that may well be the two muscle oxygen measures…we’ll see.

What did I learn from all this? Not a lot!

I learnt that changing my running shoes seemed to noticeably impact on running power with STRYD. Which is handy to know before the London Half as I was going to try and pace by power.

I don’t really have any proper baselines for muscle oxygen yet, so it was just a case of seeing it go down a bit in the short intervals and then up a bit as I warmed up but then not down as I wasn’t going THAT fast.

I suppose I could just turn up and run? 🙂


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Do you see any use of BSX on running or cycling that aren´t intervals?


warm up is good.
Never thought about that.


How do you like the STRYD? From what I can tell it calculates power based on pace (accelerometer) and grade (barometric altimeter). Does the power adjust if you’re running against a headwind or running on softer surfaces?


Nevermind, I found my answers in your review!


“I suppose I could just turn up and run?” Great conclusion. ✌


Haha, yesss. It’s really strange with all these gadgets – I hatelove ’em.

( I find them quite useful to work on my own “judgment”. I use “tons of metrics”, but I decide by my gut feeling. LOL, weird.)