Four Stryds and a MYRUN - do they measure the treadmill speed the same?

[@BobRumohr]

Very well done! Brilliant in fact. Thanks for putting in the time and effort.

[@TimGrose]

Thanks! Have you got a Stryd and if so do you see similar?

[@BobRumohr]

@@TimGrose The Stryd is on the horizon but I am getting back into running after a 10 year break. Have done sub 3hr marathon in younger times. Since retirement about 5 years ago I have been concentrating on my cycling again. Use to live in England (84-89) and rode with Ely & District CC -- worked for Northrop on the SR-71 star tracking inertial nav system at Mildenhall. So the MYRUN purchase was intended to supplement my cycling and as a way to see if my body will stand up to the pounding again. So far so good 🤪, although a nagging right achilles tendon has acted up again. If all goes well I intend to start training with power (experienced with using power for cycling) when I take running outside and the Stryd seems the logical choice.

[@movemorenowjames]

Tim, thanks for this... looking into this as use zwift a lot these days... a 4 testing system : smart !

[@TimGrose]

Stryd is definitely a good solution for Zwift. There is a lot of talk on forums that Stryds often measure "slow" on treadmills. Clearly they all do here but to differing degrees. The consensus is that they attempt to measure the speed when your foot is on the belt when typically that forces it to slow down. As I mentioned late in the video, my preference is to get the treadmill and Stryd to match (unless you are sure your treadmill is "wrong") as then it is just so much easier to see what you are doing when want to change speed.

[@movemorenowjames]

@@TimGrose thanks , good to know

[@apocreg11]

Fantastic video Tim. Thought I was going mad with my second Stryd (lost one) being slower

[@TimGrose]

Yeah I find them consistent run to run with the same one but not necessarily with other ones.

[@teamsisters1756]

Love your videos Tim, very interesting looking at all the technical data available to the modern runners. I would be interested in someone doing a heart rate strap comparison with different brands and all the extra data they show like stride length and vertical ocilation

[@TimGrose]

Thanks Liam. Good idea for a video. I have Garmin straps mainly but also a Wahoo TICKRX. Will have to remind myself what the Wahoo one can do.

[@MattSwain1]

And this is why running races on Zwift are all kinda pointless given that no 2 people are running the same distance in effect. I’ve left my Stryd Wind uncalibrated and there is a big discrepancy between it and the treadmill. One curious thing for you is that if I walk on my treadmill it matches the treadmill speed but if I walk fast enough that I can break into a jog at the same treadmill speed that immediately Stryd says I’ve slowed down by quite a lot (not far off 1 km/h). My guess is that I’m just not particularly efficient as a runner and that someone else putting out 200 watts might well be covering the ground faster than me and Stryd can’t account for that. For training purposes I don’t particularly care though, I train to the power number Stryd gives me and hopefully that will translate into better outdoor speed.

[@TimGrose]

Yeah, as I mentioned, I know which Stryd I would use in a race ha ha if you weren't "allowed" to calibrate it and, as you imply, calibration against what that is "fair" runner to runner. That said fortunately I view those "races" as more personal fitness tests. The walking thing could be that the Stryd algorithms are geared up for running. Also you start running, it may well be putting more force down through the belt and slowing it more and Stryd say they effectively are measuring your speed when you are on the belt which is typically slower than the reported average belt speed.

[@TonyJamesRunning]

Thanks for this Tim. These pods have real interested me.

[@TimGrose]

I definitely think they are good pods and indeed easily the best ones although the choice is limited. However just need to be aware that it might need "calibrating" to better match whatever baseline you want to use it against.

[@mechadriver5088]

I would be really interested in taking the same stryd, and moving it in different positions on the shoe. So, one on the lower part of the shoe (wind position) and upper part of the shoe (stryd 1 position). Have a theory that the position of the stryd affects the calibration. So potential factors affecting calibration (not proven, just conjecture): position on shoe, shoe stack, speed/pace.

[@TimGrose]

As mentioned in other replies, I have tried moving them around in the up to 4 years have had some of these and not seen any massive differences - certainly not enough to make my "fastest" Stryd no longer so etc etc. Position I think is more important for the air port on the Stryd Wind however to avoid it being blocked and getting "false" Air Power readings. I recall Stryd themselves saying it is "resilient" to pod position for measuring speed and indeed in my video the power from the Stryd Wind with much lower speed was actually the same as the other ones give or take the odd watt.

[@Teddy_J]

Thanks for all the research. I just ordered a Stryd the other day. One of the big selling points for me was the "accuracy", but based on your results that does not seem to be true. If I calibrate the Stryd based on treadmill speed will that throw off the accuracy outdoors? I would rather just trust the treadmill vs messing up the Stryd for outdoor calculations.

[@TimGrose]

I mainly use the Stryd to see what power I get. As I mentioned in the other reply, I don't have great problems with GPS. If you want to calibrate, probably best to run somewhere outdoors where you know the distance like a running track. In that case you would set the Garmin to always take pace and distance from the Stryd, run a number of laps and compare the distance the Stryd gets with how far you actually ran. You could also just use the auto calibration feature. It won't probably be quite so precise as kind of assumes GPS distance is "correct" but I find it is close. That calibration is unlikely to work the same way on the treadmill because Stryd say they are trying to measure your pace when you land on the belt and so slow it down. So if I apply the calibration for the Stryd Wind I get outside (102.5% works fairly well on that Stryd for me) to the treadmill, it is still slower than the treadmill. Stryd claim that is the "correct" speed but I am not entirely convinced as my treadmill speed feels about right - as I showed in a few other videos. I would need about 105.0% calibration with my Stryd Wind to match the treadmill. If you did the calibration procedure in Zwift it would be trying to get the Zwift and your belt speed as reported by the treadmill to match as close as possible. As I mentioned in the video that probably gives you the best practical experience in Zwift.

[@mechadriver5088]

You may want to check out fellrnr.com's pages on calibration and the stryd. This is a specific section on treadmill vs. outdoor calibration. Ultimately, he suggests a different tool for more accuracy on the treadmill that is more accurate and less painful then trying to calibrate the stryd for indoors.

[@Teddy_J]

@@mechadriver5088 Thanks Roger.

[@IRunThings]

This is a really interesting experiment. 🤔 I wouldn't have thought they would differ. When I wear my fitbit and my garmin outside they don't differ to much

[@TimGrose]

Yeah it is a bit surprising. You can of course "calibrate" each one and get them to run similarly but it is not always obvious if you only have one what is "correct" especially on a treadmill. When you say Fitbit and Garmin what metric are you talking about - pace by GPS? If so that is one plus point for GPS in that it you can't "calibrate" it and, short of being under heavy tree cover or near very tall buildings it generally works well for me.

[@keithmclean3151]

Hi Tim, just seen this video now as the link was passed to me by Stephen Cousin during a Zwift chat. Great work you have done here however I do have some thoughts and hope that you do not mind me expressing them. Excluding the Styrd Wind, the other four Styrd were assumed to be manufactured identically from the factory with no adjustments made (Correct me if I am wrong). The receiving equipment (laptops, tablets etc) were not identical. So we cannot know if each receiving device is processing it's received information the equally to each other over a given time. If the test was redone pairing the four Styrds' (excluding Styrd Wind) to different receiving devices from the first test, then that would be interesting to see. I am also concerned about the potential for discrepancy due to RF interaction of the Styrd footpods being so close together and would not be ' electrically shielded' from each other. Maybe as 'Roger L' has suggested, retest with them in different positions. We know that the 2.4GHz spectrum is very crowded (congested) so the integrity of any data sent over the bluetooth platform should always be questioned if we consider bit errors, dropped packets etc. To date I am very impressed with the performance of the Stryd footpod considering its performance compared to other footpod I have tried. In view the cost of it and comprehensive app, I would be surprised if Stryd's quality control was not 'tighter' than this. However, I am not a 'seasoned' runner like you guys so I do welcome your view. Kind regards :-)

[@TimGrose]

Hello Keith - yes I saw that reference on the Zwift Runners FB group - thanks for watching. I have one Stryd Wind and 3 of the older Summit ones so 4 altogether. Obviously I have no idea how they were manufactured and I am just using them as is as it were. I have had all these now sometime and they have always done what I showed in the video and, over time, have worn them in all sort of foot positions and with different devices running Zwift so I would certainly largely discount any such factors. There has been some talk that Garmin watches were processing Stryd data "differently" over BLE to ANT+ but I have never found that myself. Despite the "out of box" differences for pace/speed, I found they are very consistent for me run to run so applying a calibration factor does allow you get close to whatever you believe is the true speed and, interestingly, the difference in the power numbers out of the box is not significant which is good being its USP.

[@paulcain1285]

Interesting, i use Stryd Wind outdoors; hopefully treadmill arrives after 5th Feb. Will look into this as it’s a big discrepancy. I’ll probably have to calibrate for Zwift. But agree ultimately it’s extra mileage, but I’d still like to know it’s in the ballpark

[@TimGrose]

It easy enough to calibrate in Zwift to your treadmill speed if you are happy that feels about right. The good thing is the Stryd is very consistent across all paces so a simple scaling (if needed) works well enough.

[@TomvdS86]

The main question for me is what the "ground truth" is. Have you ever considered the NPE Runn sensor for your treadmill? I personally use it as my go-to treadmill sensor and consider it to be the true speed of the belt since the distance between the two sensors is set by the factory and is thereby independent of user calibration.

[@TimGrose]

I have got the now obsolete TreadTracker from RunSocial which works in a similar way - direct belt measurement. I did a similar test to this a while ago and it came within a few seconds of my treadmill over 10K but the Stryds lagged - as here. I have got the Runn but because the sides of my treadmill "slant" rather than being flat I kind of struggled to get consistent readings but it seemed "in the ballpark" for sure. Might have another go and also try and measure my "loaded" speed as it is now commonly known that treadmill belts slow as you land on them and speed up when not and the treadmill reported speed is effectively an average.

[@TomvdS86]

@@TimGrose This variation actually differs quite a bit for my treadmill, at an average 3.46 min/km (1% grade) it reports between 3.52 min/km and 3.41 min/km. Given that I'm not the heaviest of runners, I can imagine this increases with increasing weight of the runner. To capture this I've attached multiple stickers to the belt.

[@TimGrose]

@@TomvdS86 Yeah I have seen that sort of thing. Guess it also depends what, if any, smoothing is going on. Don't think Zwift do any. Current pace on my Garmin Forerunners via GPS is clearly smoothed as otherwise it would be all over the place.

[@Running_Ste]

Great video. Don’t us the treadmill that much but have noticed my Stryd is also about 1-1.5km/h slower than treadmill speed. My old Garmin footpod used to measure about 0.5kh/h quicker than the treadmill. Short answer I really have no idea of what I am actually running when on the TM 😂😂

[@TimGrose]

Remember my Garmin one always used to come up quick as well. I think, regardless of what the Stryd is actually measuring, if you feel your treadmill speed is about right then I would calibrate against it. Bit depressing otherwise going so much slower than you think you are.

[@Running_Ste]

@@TimGrose little experiment tonight. Same run on treadmill in 50 minutes: Stryd reported 10.4km distance: Stryd calibrated with treadmill belt reported 11.4km and Garmin Footpod showed 12.4km

[@TimGrose]

@@Running_Ste Umm some difference but not surprising from my experience. Did it "feel" like you had actually run 11.4 K ?

[@jarsa81]

Hi Tim, your videos always so helpful 👍 I did yesterday 6 x 1000m treadmill 2 rep 4:00/km 3-4 3:52/km and 5-6 3:45/km but Stryd shows first two about 20sec slower and then different was even more treadmill pace 3:52 and Stryd 4:18 & 4:17min/km And last 2rep 3:45min/km Stryd 4:11/km and 4:13/km why even slower last one ? I really don’t understand. My Stryd is wind version i using Garmin Calibfactor 100 but seems like Stryd shows really crazy speed numbers. I have done many intervals outdoor track and road and i can say effort and speed (feeling) not much different than outdoor, i mean i believe treadmill is quite accurate in this point.

[@TimGrose]

I rather came to a conclusion on the treadmill that it is just “easier” to note the treadmill speed/distance and use that either directly (my MYRUN transmits its speed over Bluetooth so likes of Zwift can pick it up) or adjusting the calibration of a Stryd to get a good approximation. Stryd will say they are measuring your actual speed and not the belt which typically speeds up slightly when you are in flight as it were. However, as you say, if you take the Stryd pace uncalibrated you feel are going too slow as it were.

[@jarsa81]

@@TimGrose Yes 😎 Thanks.. I am training now for Sevilla marathon next february so have to do almost all speed work on treadmill because slippery~snow and cold outside 🥶 i training by effort but also sub3 goal so nice to know speed atleast that direction 😎 I’v been using Stryd before that only outdoor and with my GPS

[@TimGrose]

@@jarsa81 Ah might see you in Seville as I have entered as well. Trying to see if I can do another sub 3 but got a lot of work to do! I was out doing mile intervals in the cold this afternoon and it was a bit icy so may have to get back on my treadmill as well if gets any worse.

[@jarsa81]

@@TimGrose Nice 👍😃 hope to see you there 🏃‍♂️and good luck for you training.

[@BrendonCamm]

Very interesting video, Tim! Did you have a fan blowing? Perhaps the stryd wind was registering that as a strong headwind and incorrectly adjusting speed? I think I'll need to do some calibration on mine, I may be faster than I think.... Wishful thinking :)

[@TimGrose]

Yeah a Wahoo headwind - but pointed at my chest! I don't seem to get much Air Power even outdoors and not yet seen any indoors!

[@TheMassif]

I’ve found your video while looking for more info on the MYRUN, and watched it for the test…really fun! How do you find the treadmill? Did you have any problems? Anything annoying worth mentioning? thanks!

[@TimGrose]

Thanks. Generally very pleased with the MYRUN. The running experience feels quite similar to much more expensive treadmills have used in gyms. If I had to be picky then it does shake a bit when I get up to the top speed 20 kph but these days I can't hold that pace for a very long at all! When I first got it (about 3 years ago) there was a fault that caused occasional dead stops but that particular issue got fixed although rarely I do sometimes get the odd one. I kind of think a new version of the MYRUN should be around the corner as think it dates from 2015 so perhaps now I might question the price as it certainly isn't the cheapest home treadmill. However the Zwift connection and the low to the ground minimalist design suits me especially being 1.95m tall and needing all the headroom can get.

[@livegreatalways]

I'm having the latest Stryd Wind. And I have to increase my TM speed by between 0.5km/hr to 0.8km/hr faster just to match the Stryd speed on Zwift. The faster I go, the more variance I need to adjust the TM to catch-up. I always thought the Stryd is more accurate as it is attached on my foot whereas the TM speed is measuring the belt speed. Should I calibrate using theZwift app or just leave it? Tqvm.

[@TimGrose]

Yes it seems my Stryd Wind is doing similar. This is a bit of a controversial topic. It seems Stryd is measuring your speed when your foot is on the belt and so slowing it down hence the typically slower than treadmill speed. For me I find this is "too slow" compared to outside based on HR and just general RPE. So it is largely up to you and whether you are "happy" with the speed the Stryd gives. Personally I find having my treadmill speed and Zwift matching so much more "convenient". As I mentioned at the end then, for me, running on a treadmill is a lot better than sitting on the couch and doing no running and all good training whatever speed it shows.

[@livegreatalways]

Thanks for your comment Tim, I will stick with the Stryd speed, I kind of like used to it by now, always adjust faster on the TM. You are right, it is all good running whatever the variances. I'm a believer that there is no such thing as junk miles.

[@TimGrose]

@@livegreatalways Yeah if you are consistent then that is the best thing. Also agree on "junk" miles. By and large the more miles I do, the fitter I am.

[@josephgonzalez_]

Ah, so if I ever get round to running on Zwift I should put in a big upward calibration factor on my Stryd and then I can compete against Sir Mo on his Woodway! Seriously though, are you completely confident your treadmill is accurate? It’s possible the Stryd Wind was the most accurate?

[@TimGrose]

Accuracy of a treadmill is kind of a can of worms. It reports the speed the belt goes at on average but, on landing on it each time, the belt will slow then speed up again when you are "mid air". Stryd have said they are basically measuring that speed when you are on the belt (which they assert is your "real" speed) so hence why all the Stryds were slower than the treadmill - albeit some a lot more than others. You have probably seen some of my videos when I attempted to compare the effort at a certain treadmill speed (according to it not the Stryd) to outdoors at same speed and I was reasonably satisfied it was fairly equitable - certainly enough to think am getting similar training effect even if treadmill running is a bit different - e.g. I tend to be 6 spm lower cadence on a treadmill to outdoors at same speed.

[@josephgonzalez_]

@@TimGrose just had a quick look at that video - yes I do remember it. “Debunking the 1% myth”. Basically you compared heart rates and found them to be nearly identical for the same paces on and off treadmill. Fair enough. I’d need to check my treadmill for myself as I’m not sure. I think I’d measure the belt length and number of revolutions in a minute and work out the speed from that. Then I could calibrate my stryd wind accordingly.

[@TimGrose]

@@josephgonzalez_ Yeah that's one of them for sure. Never going to be exact but anyway, as I mentioned, I feel a treadmill run is a lot better than no run! Do you use your treadmill much? Possibly not as you might have felt the need to try Zwift by now as not sure how I could stand the boredom otherwise.

[@josephgonzalez_]

@@TimGrose you’re right, I don’t use it that much. Well, hardly ever. Even when it’s raining and windy out I still go outside. I seem to use it more for easy runs when on double running days - which tend to be when I’m in a marathon training cycle. But I do keep thinking I should give Zwift a go, but I’d only want to run easy. When coach Kev sets me sessions they tend not to be of suitable for Zwift events I think.

[@TimGrose]

@@josephgonzalez_ There quite a few events which are a set distance (or time) but "run as you feel" bit like parkrun. The "problem" is that you can get sucked into "racing" especially late on but that is just discipline and sometimes "stretching your legs" is not the end of the world.

[@Peakabike]

9:35 how was the power for that section ? It seems strange that the power would the same for the 4 Stryds given the significant pace differences. Now the Wind would show more power due to Air Power but the other 3 should not match given the different pace.

[@TimGrose]

Fortunately it seems (and Stryd say this themselves) power is not computed as a simple of function of pace. In fact Stryd seem to imply the pace it gives does not impact power at all. Clearly power and pace are "correlated" - so I get a lot more power at a notional 15 kph than 10 kph. I think this test did largely prove their point as the power with the Stryd Wind was within 1 or 2 watts of another Stryd reporting a somewhat higher "raw" speed.

[@Peakabike]

@@TimGrose Can you share the numbers for that zoomed in section ? It sounds too good to be true for the Power to be "correct" and not the pace, if they can dial in the power it should be easy enough to back into the pace with some simple formulas...Now the position on the shoe might provide some type of explanation. Maybe you can redo the test one day with the positions switched.

[@TimGrose]

@@Peakabike Can check it out at analyze.dcrainmaker.com/#/public/df5cf11e-0382-419e-7a41-b75477818799

[@Peakabike]

@@TimGrose Thanks, yep, power can't be any closer !

[@mattbarrett6186]

Did you switch the positions of the Stryd round? Did it make a difference or were they repeatable out by the same amount? Between my stryd on track (summit and wind) they are very out for actual distance and I need to use a calibration 97.x but for treadmill, mine is curved manual self powered I need to change to 1.2x calibration to come anywhere close to road pace for heart rate

[@mechadriver5088]

This makes sense based on my experience. On a treadmill, I seem to be working harder, but my paces are much slower than expected (since I am still using a calibration of .98 from an outdoor track session). Did you calibrate based on comparative heart rate data? I actually believe the treadmill displayed pace is more accurate than my non-recalibrated treadmill stryd. So maybe add another factor to my comment prior of things (conjecture) affecting pace values: position on shoe, shoe stack, speed/pace, outdoor/treadmill.

[@TimGrose]

I have had these Stryds between 2 and 4 years and have previously had them all in different positions and have never detected any signficant differences to alter the general theme of this video that they each need different calibrations to measure the same thing. In other words my "fastest" Stryd is always that and slowest one slowest etc etc. I do find each one very consistent with itself which is probably the most important thing as then you can apply whatever calibration you find works best for your use case - as you rightly seem to do.

[@mattbarrett6186]

@@mechadriver5088 as is self powered it’s difficult to confirm the pace but speed is displayed on the screen. However the treadmill reported speed is completely out when compared to the npe runn, RunScribe and Stryd pods. I use stryd on calibration based on the npe runn and heart rate. It does vary based on position or rather position and stack when comparing any shoe and the 4%

[@mattbarrett6186]

@@TimGrose thanks Tim, mirrors me too but I’ve only had two pods so confirmation from you is good. they are both consistent where on the shoe or it up side down. The only shoe the calibration changes is the 4% and self powered curved treadmill.

[@Teddy_J]

Also, when running outdoors do you have Stryd provide the speed, cadence, and distance info to your Garmin or do you rely on Garmin's GPS data?

[@TimGrose]

I just use the GPS. Where I run it is not usually particularly challenging for GPS and, as you saw this video, working out calibration factors is a bit of a pain and not convinced they apply universally with different paces, shoes, terrain of which I change a lot. I also tend to use lap pace outside if I am really that bothered about knowing it.

[@ratemut]

Interesting topic. Well done 👏🏻. I’m surprised that the different Stryd’s differ so much 🧐. I use a calibration of 1.018 on my Stryd Wind and then it match both my treadmill and the 400m lap at the track very well. I do however experience a small difference between different shoes. Maybe another test you could do ? . Test if the Stryd meassure different on different shoes ?

[@TimGrose]

Yeah my Stryd Wind is fairly similar - about 102.5% is certainly "better" than uncalibrated. I have had all of these Stryds for some years now and tried in various positions. They may well be some differences but my "fastest" Stryd is always the same one regardless of where I put it.

[@stevenjohn9378]

Do you fancy selling a stryd? I’m after one for my treadmill 😬

[@TimGrose]

Thanks for asking but I tend to hang on to my "tech" in case want to repeat these tests! I had a look on eBay and saw several used Stryd currently for sale.

[@stevenjohn9378]

@@TimGrose I’ve not got access to eBay anymore. I hadn’t used it for ages and for some reason I’m blocked on it. They Won’t give me an explanation as to why. I honestly didn’t knowingly do anything wrong. Quite frustrating. Thanks for the reply ….. I’m trustworthy honest 😬😆

[@ZwiftRunChannel]

I hope you don't mind me adding my similar test here from last year. I only used two Stryds against the MyRun treadmill in a similar MeetUp but not a race. I had similar results re the Stryd Wind being the 'slowest'. kzbin.info/www/bejne/hIiTlJRqgpd5r9E

[@TimGrose]

Sure! I wondered if you had done one but could not remember and you have been busy running with Eddie "all day" :) Will go and watch now. I used a meetup as thought easiest way of ensuring we all set off at the same time and with the "private" feature could just see the 5 "runners" of interest in "Riders Nearby" and not other runners and riders.

[@RunForPeace-hk1cu]

That's like $1000 worth of Stryd pods. 😬

[@TimGrose]

Ah I did buy one "second hand" and got one given to me so perhaps half of that in overall expenditure :)

[@PoetWithPace]

Let me guess......they don't measure the same? :-)

[@TimGrose]

Spoiler alert but correct - no - not without "calibration" which did not do here to illustrate the point.

[@PoetWithPace]

@@TimGrose i doubt any form of calibration would make it 100% accurate, if my experience with tech and treadmills is anything to go by. According to my calibrated Garmin i am often running 2:30/km pace on a treadmill :-)

[@xelionizer]

You will not get the same reading when you mount the pods the way you did (over/under). If you want to do an honest comparison, you should mount them side by side on one shoe only! The data you are comparing is non-sensical!

[@TimGrose]

Well thanks for your "confidence"! This is obviously not meant to be full on scientific research but I can assure I you that I get similar results to what I got here however I mount them.