Zwift & Outdoor Running with Stryd - Is it the same ?

[@hobscotch6161]

I purchased a mid level treadmill a few years ago as I was changing things up from doing hours of cycling each day, I found the treadmill to not just be way harder but I was also much slower over a given distance. I would predominantly do trail runs around a few forest loops that I have near me so these are never really flat but doing the same distance on a treadmill I was minutes slower. I had the treadmill setup with a 1 degree incline. I can only think that either I had hideously poor technique on a treadmill or that it was way way off in calibration, I may get it fired up tomorrow and linked to Zwift see what happens after a calibration with a Garmin foot pod, not used Zwift run before. Nice vid BTW...

[@TimGrose]

I wonder if there was an element of boredom on the treadmill ? Before Zwift, treadmill runs seemed very dull although TBH I do like getting outside when I can. I seem to recall my tests here showed that 1% on my treadmill (a Technogym MYRUN) was harder than outside so that could be another factor.

[@hobscotch6161]

@@TimGrose Thanks for the reply, I will try a few thing and adjust incline to see if it makes any difference, not had a chance to check calibration yet but will in the coming days, something fundamental had to be way off as a 10k treadmill run should be quicker than a hilly single track trail run. Boredom could also be a factor and thus motivation I guess.

[@TheWelshRunner]

Really interesting video. Thanks for sharing. As you know I am getting some bizarre readings with my Stryd on the treadmill and will do some investigation. Would love to see this repeated in windier conditions and using a shoe without offset laces. 👍

[@TimGrose]

Thanks. Yeah that would be a good follow up test. Think need to do some video analysis of my seeming different styles indoors and outdoors too. Do you see that at all?

[@davidkaplan5517]

I think it’s got to do with RPE inside with no air flow increasing exertion for less output.

[@thomasschwarz1973]

Wonderful, thank you. Great background for me, just getting into a treadmill (x22i comes on Jan 5th), and I am very interested in progressive speed training. Cool that you have chosen 13.8 kmh/ 7 min mile. Choosing a speed/ aerobic stable speed, is a wonderful way to approach both physical strength/conditioning as well as aerobic efficiency.... ...still in the gym, I just got to 11 kmh, stable for 5 minutes, but very high HR 160, so I am looking forward to that coming down and jumping into 12 KMH. My goal is 16 KMH (6 min mile) as a stable, comfortable pace....

[@TimGrose]

I recall in this video, it was picking a speed that was hard enough to get the HR up to a decent level to compare treadmill and outside but not so hard was fighting lactic and stuff. You must be looking forward to the 5th then.

[@BrendonCamm]

Now this is a fantastic idea for a video!! I've often wondered if the Stryd would give different readings depending on what shoe I'm wearing as typically (for me anyway) my gait changes depending on shoe choice. I'd love to take a look under the hood at the Stryd software to see what's going on, not sure if they even take gait into account for power readings.. The wonders of technology :)

[@TimGrose]

Yes whether the fact I get a different cadence on a treadmill could be a factor in why the Stryd measures “slow” is another thing to look into. I have 4 Stryds (1 wind, 3 of the non wind ones) and they all need quite different calibration factors to best match outdoors. They are consistent with themselves run to run but what is it in the innards that causes such variation device to device.

[@user-yl7lz1hm6r]

@@TimGrose What got you in the position of owning 3 non wind?!

[@TimGrose]

@@user-yl7lz1hm6r Like shoes - more the better :) Actually I bought one originally but the charger and spare clip got effectively nicked as was in a bag stolen from my car, so I then bought another one 2nd hand from a friend who was selling up then got another later in a similar way to help my testing for these sort of videos.

[@user-yl7lz1hm6r]

@@TimGrose you have the ultimate running toy shop!!

[@TimGrose]

@@user-yl7lz1hm6r Ha ha - I think I could do with a 2nd Stryd Wind though :)

[@jennyt2732]

I have done a little testing too, though nowhere near as comprehensive as your tests. I use Stryd speed for both indoors and out. Here are my results: Outside, 0% wind, flat, straight tarmac: 4:00min/km pace, power: 219w, VO: 8.00cm, LSS: 10.4kN, GCT: 180ms, cadence 182. Inside on 0% incline treadmill (LifeFitness), 4:00min/km pace, power: 220w, VO: 7.63cm, LSS: 8.1kN, GCT: 200ms, cadence 180.

[@TimGrose]

Ah that’s interesting as quite different. Very similar power which is promising but you had a lower VO on treadmill which was complete opposite to me. Cadence closer too but GCT quite different whereas I was the same. Did it feel about the same intensity and what shoes were you wearing? Maybe I need to try in less “bouncy” ones than NEXT%

[@jennyt2732]

@@TimGrose Yes I think the intensity felt the same. It's very rare to get zero wind outdoors and it's great for me when we do. Wind affects me a lot. I was in standard Mizunos indoors and trail shoes outdoors.

[@jennyt2732]

@@TimGrose My LifeFitness machine has a shock absorption system, which may explain my lower VO, lower LSS and higher GCT compared to road.

[@Thecarpenter1983]

Hi Tim, do you remember the speed of your treadmill ? I bought the strydpod and when a i run at 7.28 min/km the treadmill have to be at the speed of 9.8 km/h. In facts, it’s to fast to be a real 7.28 min/km according to my feeling

[@TimGrose]

It’s a well known issue that a Stryd will tend to measure less than what the treadmill says. They argue treadmills slow when you are on them and speed up between strides when you are not and they are sort of measuring the loaded slower speed. As you say RPE suggests you are going faster than the Stryd says. I recall my takeaway from this test is that my treadmill reported speed was pretty close to how that same speed feels outdoors.

[@Thecarpenter1983]

@@TimGrose thank you !!!

[@tyecm]

My numbers, without doing any sort of verification, appear to agree with your findings on two points. My SPM are also 6 less indoors than out, also I also appear to generate slightly more power outdoors that in. I tend to run well to the front of the TM deck, as evidenced by shoe scuff marks on the deck toe plate. In response I'm attempting to keep further back to see if my stride length/SPM change.

[@TimGrose]

Interesting Chris. I think I also run to the front of the deck but perhaps to avoid a feeling of falling off!

[@russelllipscombe6614]

Hi Tim, really interesting video. Do you have any comments on the difference in the Stryd pace inside and outside? There is a 15-20 second per mile difference which ties up with some other videos I have seen (and the Stryd website) on the difference between treadmill speed and actual speed. Do you think that this might account for the difference in power between inside and outside as effectively you were running slower on the treadmill?

[@TimGrose]

Yeah that difference seems to be a constant topic of debate. The tests I do in these videos and just my general feeling is that when am on my MYRUN treadmill then the effort needed to run at what speed the treadmill says is quite similar to outdoors and the "uncalibrated" pace from the Stryd somewhat slower. In turn pace and power seem highly correlated on the Stryd. That said not all Stryd foot pods are the same - I did another video where was using 4 and they came out somewhat different. Interestingly though the power numbers were much closer aligned suggesting they do something "clever" with power that does not necessarily align directly with the pace it effectively reports. I have rather moved away from using the Stryd as a key part of my training stats. On Zwift it is just so much easier to take the treadmill speed so they match anyway. Outdoors, most of the time, I feel pace and HR and just general RPE tell me most of what I want to know. One thing I have "learnt" is take uphill sections easier as obviously pace will decrease for the same effort. Have you got a Stryd yourself?

[@russelllipscombe6614]

@@TimGrose Not yet though I have one on order. I am trying to understand how best to use it and have found your videos very useful

[@leegod100]

Hey Tim, nice video! 👍 Surprised you didn’t use the Stryd to set the distance/pace on the treadmill?

[@TimGrose]

Hello Lee. Why would I? The treadmill gives a speed which I believe is about right as I was effectively trying to illustrate in this video. The Stryd suggests I was running somewhat slower on the treadmill but more or less "correct" outdoors.

[@leegod100]

@@TimGrose personally I would assume Stryd pace/distance to be more accurate than the treadmill.....but that aside it could have also been interesting to see the data and comparisons for 7.00/mile via Stryd both indoor/outdoor. Looks like your TM is pretty accurate though. I used a gym recently it was totally different!

[@TimGrose]

@@leegod100 Yeah the main use of the Stryd in this test was for power which Stryd themselves say is independent of whatever speed the Stryd reports. I have had this treadmill for over 2 years now. If I thought it was way off then I like to think that I would have asked for my money back and/or a replacement! Also logical for treadmill users to run according to what their treadmill says especially when it costs over £3000 and not what a £200 gadget might say - even if that might be "accurate". But therein lies another issue and perhaps another video to talk about Stryd reported speed. That is a can of worms as I have got 4 of them and "out of the box" they would all measure the treadmill speed differently so then which of those is "correct"...

[@leegod100]

Tim Grose I appreciate why you'd want to trust the treadmill! Just assume you use the same device and it measures speed consistently the same indoor/outdoor (after all, this does makes sense as it's effectively motion capture and doesn't 'know' you're actually moving or not?!).....then it would have just been interesting to see the comparison for same reported Stryd speed. Just another way of testing it. I do find it interesting how many users experience this TM v Stryd difference and rarely consider the TM first (not suggesting that's you btw). Would be interesting to see calibration comparisons on two 'out of the box' Stryd Wind. Although i think it's reasonable for any measurement device to have a calibration factor, and obviously each device would be different. I guess it's only really relevant when you start comparing it to other measurements....like TM, GPS, 400m Track. I'm not a Stryd fanboy but I do think people give it an unreasonably hard time!

[@TimGrose]

@@leegod100 Now in lockdown again in the UK, I think the treadmill maybe my best bet for my next shoeoff so will see if can include some Stryd reported pace as well.

[@novagaski7007]

Good info and appreciate you giving this a try! I’m new to Stryd but have been interested in Stryd pace indoors on Zwift vs Stryd outdoors so I can do race-specific testing and training on the treadmill. I have an older treadmill so I doubt its as accurate as yours and looking to Stryd to try to keep virtual efforts consistent with live as much as possible.

[@TimGrose]

If you are uncertain about your treadmill speed accuracy then using whatever Stryd says is probably sensible especially if you have calibrated outside against a known distance. You probably won't be going artificially "fast" if so. Remember if say the calibration is on a Garmin watch then Zwift won't know about that and may want to use Zwift's own calibration procedure for foot pods which you can access from the Run pairing screen.

[@livegreatalways]

Wow... Your HR is so low for the speed, any tips to share how you do it? My TM always say I'm faster vs my Stryd. To get the same speed in Zwift, I have to always set 0.7km/hr more. At lower speed the difference is lower at 0.5km/hr. I always thought the Stryd is the accurate one but you seems to suggest otherwise. Tq for the Video, Tim. Happy new year to you and family.

[@TimGrose]

Sadly my low HR these days is more reflective of my 54 year old self! 220-Age max HR works quite for me. Back in the day I got to 193 in my late 20s. These days 164 is highest have seen of late and even that is very rare for me to get to. Yeah it seems most people get slower speeds with Stryd "uncalibrated". They will tell you your treadmill is "wrong" and/or it is measuring your "actual" speed and not that of the belt but, for me, I think my treadmill reported speed is "about right" and I am effectively trying to show that in these sort of videos. At the end of the day as long as it is "near enough" then that's fine for me. Treadmill is just another training environment for me after all. Happy New Year too.

[@livegreatalways]

@@TimGrose no worries, we all aged and you are stil damn fast, 10-20 years younger still can't beat you. BTW, really like the frame photos the wife gave you. Awesome lady!

[@jennyt2732]

@@TimGrose The actual speed you achieve on a treadmill would depend on the strength of the treadmill motor vs. your weight, so two people testing the same treadmill could get different real speeds. I have tested Stryd over 14k outdoors together with GPS and got a difference of only 30m, so I am pretty happy about that.

[@TimGrose]

@@jennyt2732 Good point. May have to do a video to try and test that!

[@MaxwellMcKinnon]

Cool thanks for the video! Have you figured out the cadence difference?

[@TimGrose]

Thanks and well reminded. Not really to be honest. That said, I have noted a slight tendency outdoors for my cadence to increase slightly as I get more tired. Perhaps when fresher I am striding out "better" and more like on a treadmill with the "perfect" surface. Maybe also an element of slightly higher VO on a treadmill. Probably need to do some comparison filming for a closer look. Could do with "finding a friend" to film me for longer outdoors too when lockdown is eased. Any thoughts yourself on this?

[@MaxwellMcKinnon]

@@TimGrose i have no idea. I was surprised it was so close to begin with. I thought treadmill running is like picking the legs up and down (same cadence and recovery stroke) but the push forward part of the stroke is way different since it’s really the belt pulling the ground foot back. I don’t though though, I’m just a kid.

[@leonal2680]

Were you running at 1% incline on the treadmill? When i run on the treadmill I experience the same 'more bounce' feeling which is independent of the shoes that I'm wearing hence I believe this results in longer strides and requires less cadence to maintain the same pace

[@TimGrose]

No 0%. I did another video where I found it “harder” compared to outside at 1%. Interesting your shoes don’t seem to contribute to your “bounce”. I was however in the NEXT% which are obviously bouncy!

[@josephgonzalez_]

Could the difference in cadence be correlated to the vertical oscillation? Yeah, not a huge difference between the treadmill and the road in your test but definitely slightly more effort required outside. As you imply, I think on a windy day the effort level would go up further. I’ve just ordered a stryd power meter - looking forward to using it!

[@TimGrose]

Yeah not sure whether the higher VO is causing the lower cadence or vice versa. Higher VO seems “helpful” on a treadmill as then let the belt run under you more! Will have to check with much less “bouncy” shoes like say Streak LT4 or Adios 5.

[@josephgonzalez_]

@@TimGrose my hypothesis is that the inherent bounciness of the treadmill (relative to the road) is causing the higher VO which in turn is influencing the cadence. And yes I guess added bounce from shoes would amplify the effect. Better get your white coat and clipboard and get testing 😁 👍

[@TimGrose]

@@josephgonzalez_ Ha ha. Maybe time to get the Streak LT4 out again. Very little “bounce” in them!

[@sebastianocabras8931]

buon giorno vuole calibrato? Quando si usa con zwift? grazie

[@TimGrose]

Hi. I think you are asking about calibration of the the MYRUN treadmill with Zwift. You don't need to as the speed of the treadmill is picked up by Zwift over Bluetooth. So whatever speed the treadmill is going at, is the speed I go in Zwift.