Friday, January 20, 2023

Next Gen Stryd in Depth Multi Tester Review: Road, Trail, Treadmill

Article by Mike Postaski, Joost de Raeymaeker and Michael Ellenberger

Next Gen Stryd ($249 or $149 plus min 6 mos x $9.99 for personalized training content)

Introduction

In this article and in depth review we bring you the Next Gen Stryd experiences of three RoadTrailRun contributors after 2 months of extensive testing:


  • The Stryd “rookie” Michael Postask (Mike P.), a top ultra trail runner from Idaho and 2:39 marathoner who will focus on the trail side of Stryd and its use and utility there

  • Michael Ellenberger (Michael E.) a 2:22 marathoner and Stryd user since 2018

  • Finally, Joost de Raeymaeker (Joost) a 2:26 marathoner at age 51 in 2019, and 3 time age group World Marathon Majors winner and the “old pro” having used every version of Stryd since 2017 for 99% of his runs.


According to Stryd the next gen Stryd is updated to include

  • 5x improved responsiveness for the most accurate pacing

  • track lower body stress to keep healthy and sustain your performance

  • new running profiles to tailor power pacing to your workout conditions

  • sprint accuracy for tracking improvements in speed work

  • upgraded sensors

  • new advanced materials

  • next gen design

Let’s find out what the guys discovered during their extensive testing!



Mike P: I’m the Stryd newbie here, as well as the designated trail tester in our test group. Since the others are long-term Stryd users, I’ll leave it to them to cover the intro and technical details and focus on my experience as a first time Stryd (as well as power data) user. Now when I say “newbie”, I have to reiterate that I’m a true newbie in terms of both using any foot pod as well as the concept of measuring “power” itself when running. Even when I was offered to test the device, I truly had no idea about its features and capabilities. After receiving the Stryd pod, I literally had to look up and research everything about it, having no idea what to do with it. It’s been a fascinating experience, and hopefully I can highlight some of the most interesting aspects for any potential new users out there. For context, I’m primarily a trail runner, but I do hit the roads from time to time as well as the treadmill. 


Michael E’s Introduction/Background: I’ve been a Stryd user since 2018, and have written reviews for RoadTrailRun accordingly, including my first investigation into the Stryd + Apple Watch combination in 2018, which I still maintain is a top-tier running combo, and a small supplemental update in 2019. I’ve owned and used Stryd since then (and owned every Apple Watch, similar as they may be), and was thrilled to test the “Next Generation” unit. From the hype videos on YouTube to teasers on Instagram,I couldn’t wait to get my hands on the latest gadget from Boulder.

I’ll also add, because I don’t know where else to put it, that the customer service/outreach team at Stryd is, in a word, superb. Ask a question in their (hyper-active) Facebook group, and Gus will get back to you crazy fast. Pose a question on Reddit, and someone from Stryd (also Gus?) will respond in turn. Use their formal request channels - and they’re still uber helpful. I’ve never had a bad experience in posing a question (technical or otherwise) to their team, and it stands as a major reason to buy the foot pod - they support their product.



Joost: 2017. I just checked. That’s when I got my first Stryd. My original order confirmation email perfectly shows the kind of care and attention I’ve come to expect as natural from them. 

Like many others, I probably wasn’t really sold on fully converting to power for my training, but an article by fellrnr.com on the Stryd and its accuracy had me convinced. 2017 was a time I also wanted to dig a little deeper into my running, while I was preparing for my bid to podium in the Marathon Majors after my 50th birthday at the start of 2018. Apart from the Stryd, I also got the very first RunScribe pod, which provided a lot more data still, most of it numbers that hadn’t been profoundly analyzed yet as to their impact on speed and injury.


About accuracy as the main reason for getting the Stryd: It’s not that Luanda has that many tall buildings, but along the strip of land we call the Ilha where we were training at the time. There’s a stretch with very big leavy African fig trees where my pace would always be completely thrown off during my interval training. Something that didn’t rely on GPS to get speed and distance seemed like a great choice. Power wasn’t a primary deciding factor, since I was mainly training on pace and distance.


Since then, I can say that 99% of my runs have been with a Stryd on one of my shoes. I say “a” Stryd and not “the” Stryd, because this review pair will be my 5th pod. This could sound like the hardware isn’t all that great (which it is). It’s actually a testimony for the exceptional customer support I’ve been getting from the company over the years.


A short story about Stryd and me:


The one I got in 2017 was their original foot pod. It was extremely accurate out of the box, but unfortunately stopped communicating with my watch after 10 months or so. I promptly received a replacement unit free of charge at my Angolan address. Stryd 2 needed calibrating, but was great after that, until right around the time when the wind Stryd made its debut. The battery in my working Stryd started inflating to the point where the pod itself burst open. While waiting for my wind Stryd to arrive, I proceeded to perform some surgery. Opening up the first generation Stryd (the one that stopped communicating), I got its battery out and replaced the second version Stryd’s battery with that one. Stryd support was helpful as ever, even suggesting which type of glue I could use to make the rescued pod as safe as possible. It worked a charm and when my wind Stryd arrived, which I got at a nice discount because of the issues with the battery on the other one, I gifted the rescued one to a running friend. To my knowledge, it’s still working.

Then came Luanda’s most epic race which usually is held on New Year’s eve, but postponed to March 2022 due to the pandemic. The start was especially chaotic and while almost being trampled, my Stryd got knocked off my shoe. After the race was over, we went back to see if it was somehow miraculously lying there somewhere, and it was. Unfortunately it was also completely mangled by thousands of feet and traffic after the race had started. So that’s how I got my fourth Stryd, again with a fair discount, and which I would still be using today if not for the opportunity to get my fifth one: the all new faster and more rugged Stryd.


So what’s changed for the people who already own a Stryd?


If your Stryd is from before the “wind era”, you’ll of course get air resistance added to your overall power (and as a separate metric afterwards in Stryd Powercenter, the company’s online platform).


On the inside, there’s 5x more responsiveness, coming from faster sampling and processing and the capability to capture lower body stress. The latter hasn’t been particularly useful for me so far, since the metric is mostly a reflection of my running stress and power output, but I imagine it could be useful at some point when there’s more data available and you can compare lower body stress per body weight with the general user base and reach some sort of conclusion.


The faster processing has the added benefit of allowing for faster reaction during sprint intervals. The ability to react faster to pace/power changes as compared to GPS was already an important reason for training with Stryd power. This has gotten better still with this update.

On the outside, quite a bit has changed as well. The back of the pod itself is now reinforced to avoid wear and tear due to clipping it in and out of its cradle. The bottom has also become patterned to help with shifting around on your shoe.


The clip itself now also has some extra patterned rubber on the top and bottom to help with this. 


It’s now possible to actually use the Stryd on a single crossed row of laces without any issues. The picture above shows the earlier wind version of the pod (the hole is where wind data is measured) on the left and this new version on the right.


Features:


Distance & elevation

Mike P: In researching the most basic features of the Stryd pod, and footpods in general, I was quite shocked to discover that they could purportedly measure distance and elevation more accurately than GPS. I had no idea about this, and didn’t quite grasp the ramifications of this immediately. I first focused on some rudimentary testing - running known routes, running with two watches (one GPS measured, the other Stryd measured), and some treadmill testing. I found distance and elevation measurements to be extremely accurate, indeed more so than the GPS on my watch. 


Aside from the pure accuracy, this is a great feature because it eliminates the need for waiting around for a GPS signal to start your run. Everyone has those moments where you stand around waiting for your GPS signal to lock in before starting. Or being in a group and waiting for that one last person to catch a signal. This is quite annoying, especially if you’re in an urban area. When I used to work in NYC and start my runs from midtown, I would only start/stop my watch in Central Park when I (usually) had a signal. I would manually log the time and distance separately in Garmin for the sections to/from Central Park. There would either be no signal at all, or it would be wildly inaccurate with all the tall buildings. If you live in an urban area or city - this feature alone is a game changer.


Even here in Boise, I find this feature great as I often run through the downtown area to get to the Greenbelt. I no longer worry about zigzagging around, passing through the occasional tunnel, going through tight alleyways, or anywhere that might lose GPS signal. On trails, the signal issue can also be beneficial if you run through forested areas or tight canyons, etc. In theory you’d also get greater accuracy as there’s less straight line tangents when running trails than on the roads. I have a few standard loops that I run - for one 4 times around a loop run I got measurements of: 2.17, 2.19, 2.19, and 2.18M.  



Elevation gain also seems to be quite accurate. Elevation is harder to judge as different watches as well as mapping sites tend to give different measurements. I’ve found my Fenix 6 to be very accurate over the years, and the Stryd pod tends to in general match it. I’ve compared some routes and sections to previous data and the elevation numbers are relatively accurate - as accurate as you would need them to be.



Treadmill distance measurement is also another great feature. On my home treadmill, I get drastically different measurements from my Fenix watch vs. the treadmill itself. For 100% of my treadmill runs, I have to make a note of the distance and then go back into Garmin and update the data manually. Once I started using the Stryd pod, I got distance measurements extremely close to the treadmill - within a 0.10 mile difference per hour of running (My treadmill is way more “accurate” than the estimates my Fenix 6 gives).


It appears to be more accurate for steady state moderately paced running. I typically do alternating running/hiking sessions and this can introduce slightly more variation in measurement, but not much. I actually think my treadmill doesn’t measure correctly the more pace/elevation switches you have. I typically do sessions like 5-6 sets of (10:00 @ 3.6 mph/15-20%, 5:00 @ 6.0/1%). Ultimately - I no longer have to manually adjust the distance for my treadmill runs. (Note- I will discuss treadmill elevation in a section below).


Joost: Mike covered what the Stryd can do in terms of pace and distance extensively. After all, it was also the reason I got my first ever version. Some nuance is due. 


As I wrote, my first pod was spot on. I could do track workouts and my watch would beep right on the line every single time. 


My second Stryd was a bit too optimistic, so I had to calibrate it and after that, it was as accurate as my first one. 


All my later versions have needed a bit of calibration and are fairly accurate after that. I say fairly, because ever since plated shoes, exotic foams and all sorts of different heights, drops and geometries have arrived, there has been some shoe to shoe difference, something that in all fairness is not major, even though in most Stryd support groups, people will continue to tell you that it’s very accurate and that what might be at fault is the way we measure and calibrate our devices. 


One of the issues with a distance error on the Stryd is that it will be cumulative on your run. Every km or mile will add or subtract the same amount from your total, while GPS errors are not cumulative. You might get an error running in a street full of high rises and your distance may be short, but the next km or mile, it could be long. The overall result could lead to less error with a GPS based workout than a merely Stryd based one. I say could, because normally the Stryd will be a lot more accurate in these situations. If you feel that your pod differs too much between various shoe models and you don’t want to measure and remember a calibration factor for every one, you can always set your watch to get the distance from GPS. 


Even if you use an Apple Watch, this is possible if you use the iSmoothRun app instead of Stryd’s brilliant own iOS and Apple watch apps.



But all this focus on calibration and distance kind of misses the point of one of the great reasons to use a Stryd, even if it is a couple percent points off. It is incredibly consistent, meaning that the same pair of shoes will always measure the same distance. While GPS might be short one day, it could be long the next, leaving you with no means to consistently measure and compare your efforts.




Running Power - The Idea


Mike P: I’m aware of measuring watts for cycling, but I was not at all aware of the idea of measuring watts for running. As a trail runner interested in measuring and planning my training, it’s a bit more complicated trying to come up with pure numbers or “scores” for training data. For road running it’s a bit easier, as you don’t have to factor in variations in terrain/surface. Elevation gain is usually much less for road running, and with a generally smooth surface, that can be accurately accounted for by normalized grade pacing. 


For trail running, there’s also more of a muscular component, especially when big gradients come into the equation. A while ago I found a mechanism to roughly account for these factors - essentially using heart rate as the primary measure for trail runs, and adding in an adjustment factor for elevation.


I use TrainingPeaks for my training, and as far as planning and scoring my runs, I use separate grading for roads and trails. Note: TrainingPeaks uses TSS (training stress score), while the equivalent in Stryd is RSS (running stress score).  In TrainingPeaks, for road runs I use ‘rTSS’ which is essentially based on normalized graded pace. For trail runs I use ‘hrTSS’ plus an elevation factor (10 tss points per 1000 ft of elevation gain).  It’s basically a measure of effort based on heart rate zones, then adding in a factor to account for elevation. There’s no perfect way to score trail runs, and it becomes even more dicey the more technical or difficult the terrain/conditions are. 


Using power to score runs seems very enticing as in theory it could cut through those difficulties of measuring output for trail running. Heart rate of course is not a perfect measurement due to natural variations, cardiac drift, and other factors. Then throw in technical issues with the sensor not reading properly - too dry, too windy, synthetic fabrics, etc.  For the reasons stated above, going strictly by pace on trails is not generally feasible, or at least not easy. The idea of having a relatively stable and accurate “output” measurement (watts) to measure on-the-fly and afterwards could be a game changer (if it works).



So why would you want to use power?


Joost: First of all, what is a Watt? Power is a result dividing strength by speed, so it is a measure of the force you output in a predetermined measure of time. You can measure it in Watts (Watt=joule/Second) of horsepower. It’s fairly easy to see why a metric measuring your work over a determined period of time can be useful, not only to calculate instant energy expenditure, but also to easily add up whole workouts, weeks, months, years, to get an idea of the amount of work you’ve been doing.


Unlike cycling power meters, there’s no way to directly measure power while running, unless you’re using a force plate treadmill to measure your output. 


Stryd came up with a way to measure power with an algorithm, based on the output of an internal accelerometer, gyroscope, altimeter, and wind meter. There’s also a temperature and humidity sensor inside, which are probably used to calculate some of the other metrics, but their readings are not separately available.. From what I understand, Stryd calculates pace, ground contact time, vertical oscillation, distance, cadence, form power, leg spring stiffness, wind power and of course power itself, which I always understood was calculated in Watts/kg and then multiplied by your weight to get the reading in Watts.


One important implication of this is that when using Stryd, it’s best to leave your body weight set to a certain value and not change it, unless of course you’ve gained or lost a very large amount of weight. Otherwise, all of your measurements will be off and you’ll have to start from scratch to measure your Critical Power (more on that later) again, or let the platform calculate it for you based upon your workouts, which might take a while.


So back to the why of power. It was fairly obvious Watts are a universal way of measuring work and this in and by itself is a good reason. 


Keep in mind though, that there is currently no standard way of measuring or watts for running, so every platform that embraces Power for running has its own way of doing so. This means that 300 Watts from a Stryd will not be the same as 300 Watts from an Apple Watch or a Garmin (unless of course you’re using a Stryd to measure power with those watches). Coros watches seem to be pretty close to Stryd in terms of power values measured with their watch.


Imagine going on a tempo run on the track without power as your main metric. You’ll run a certain number of laps around the track at a certain pace, rest and repeat. Using a Stryd, this wouldn’t be any different, except for the fact that you would be looking at Watts instead of pace. Now imagine the same tempo run on a hilly road. Going uphill, it’s usually impossible to maintain pace and still be in your required workout zone. The same goes for downhills. When using Watts, you measure the power you’re using and you can maintain your power going uphill (effectively slowing down the exact right amount to stay in your predetermined workout zone) and also going downhill (speeding up). The effort to stay in your tempo zone will be easily maintained, making for workouts that are a lot more effective and accurate. The same goes for wind and air resistance. 


Another reason to use power is for short and fast intervals. GPS usually takes a while to get the right pace dialed in as you accelerate. With Stryd, and especially this new version with faster measurements will reflect almost instantly when you change your pace.


Yet another reason  to use it instead of other metrics like Heart Rate zones is that where I live in the tropics, heart rate is always going to be higher than where we race. Power is just a lot more reliable as a measurement of output and effort.


Watts on the Run:

[Real-time watts]


Mike P: The essential idea is that when you are running, the Stryd pod generates a single power number which is a measure of your “output”. It factors in your pace, as well as elevation, and even wind. I’m sure it accounts for many other factors as far as the acceleration of your legs, rebound off the ground, vertical oscillation, etc. You can really get into the weeds as far as how Stryd determines all of that data, but in the end it’s all proprietary, and you essentially have to “trust” the end result “Watt” number that it comes up with. The best way is running with the pod for some time, paying attention to the power data, and factoring in your experience with other more established metrics such as pace, HR, elevation, etc. and determining how it feels for you. 


I think the best place to start, especially for newbie power data users, is to list out my general observations over 2 months of usage:


Steady, accurate, real-time data on the run

Mike P: I found the power value (watts) value to be very “accurate” on the run. “Accurate” in the sense that once you accept watts as a measure of your running output - changes in that value on the run seem to be in line with changes in your pace and effort generally, while factoring in changes in elevation and even wind. 



See the summary data from a trail run above - it’s 3 laps of one of my typical loop routes. I like to do loop runs often as it’s good practice to dial in pace and effort. First of all - you can see the distances of each loop are within hundredths of a mile - distance really is very accurate! Also you can see the power numbers are identical (I actually wasn’t trying to do that - I tend to have some loops so dialed that I can run almost identical times over and over without checking my watch). In any case, you can see the times of each 2.66M loop are within 1 second - with the exact same 219W value! Pretty much proving that the power data is at least relatively accurate. Also note slight HR increase at the same effort level - demonstrating some typical issues when guiding output strictly by HR. Cardiac drift is a much bigger factor in warmer temps of course. 


On the run, the advantages of using power as a guide are apparent. My loop route has no big climbs, but does have some rolling sections, and a few sections which are enough to raise your HR on the incline, and drop it quite a bit on the decline. If you were strictly looking at either pace or HR - it would be difficult to gauge the right pace/HR at any given time in order to keep effort steady over the entire run. With power data, you can just stick to a pre-planned range (or go with the flow) and try to keep the power output number generally steady over the course of the run. This would entail slowing over hills and going faster on declines, generally speaking. But in terms of guidance - the watt value is much more accurate and easier to follow (on a rolling or mixed grade course) than pace or heart rate.


You can set the display of the Stryd Zones Data Field to include lap power as well as Real Time Power. You can also smooth out the Real Time Power using 3s, 10s, or even 10s rolling averages. But I find the Real Time Value to be most accurate and not jumpy enough to be an issue. 


Note- (for a Garmin watch) you cannot simply add the power field/value to an existing data layout, you have to add a separate data screen with the full Stryd Zones IQ Data Field. 


If you try to add the Stryd Zone field into an existing data screen layout, it weirdly gets cut off/squished to fit the size of the data field display area that you choose. I was trying to get lap power, power, and add lap time into a single screen, but couldn’t figure out a way to do it on my Garmin watch. I’m not sure if other brands handle this differently or better.


Power on trails vs. roads - soft surface measurement & the super shoe factor


Mike P: A watt is a watt is a watt - right? What does that mean exactly? Basically - a watt is only as accurate as it can be accurately measured. What I found, in using the Stryd pod for both trail running and road running is that the watt values and calculations are inherently skewed towards the most accurate conditions to record the actual data, i.e. smooth, flat roads. Once you throw trails into the mix, terrain factors such as grades, rocks, sand, snow, uneven surfaces, etc. tend to lead to lower power readings. 


In my testing I found that the softer the surface, the more wattage seemed to be “sapped” from the output readings. This makes sense if you think about it, because if you’re running in soft sand for example - the pod can measure it, but it can’t necessarily tell if you’re putting more effort out into softer ground, or if you’re just running slower (measured via longer ground contact time and likely shorter stride length).  Now, I’m not here to say that the pod is necessarily measuring “wrong” - I’m just saying that there’s some obvious limitations to what it can tell about conditions, and a lot more so on the trails vs. the road.


[A snippet from a trail run - at this point I had a defined Critical Power of 336W - based on a road 5K. I was trying to run somewhere above 300W for 30:00 to see how it felt on trails in comparison to the road. The trail conditions were not ideal that day, but I was going pretty full out under the (non-race) circumstances, and I couldn’t get near my modeled 331W value which was based on road running]


Once you scroll down below - you’ll see that the main determining runs in my “Critical Power” (read on) are all road runs - and in fact, in the Nike Vaporfly Next% 2’s. So an important consideration to keep in mind is that when using power as a training guide, power numbers should be taken in context of runs of a similar type, on similar terrain, in similar conditions, etc. (even in similar shoes).  I.e. you should be careful not to use power numbers from road runs as a guide when running out on the trails.


Running hills - ups, down & power hiking

Mike P: If the goal of a run is to maintain steady effort throughout - we all know we need to slow down on inclines. But, I found it astonishing how much and how fast the power number went up even on moderate inclines. A big advantage of the Stryd pod is the instantaneous feedback of the wattage whenever the grade changes. It’s once again much more advantageous than pace or heart rate. Using pace - on an incline your pace may slow drastically in relation to your intended average pace, making it difficult to gauge an even effort, especially for less experienced runners. Heart rate has the obvious disadvantage of lag - your heart rate may not respond until you’re well into the hill, making it practically useless as a gauge in the initial stages of an incline. 


On the other side (downhill) - the power number definitely drops. This makes sense and is obvious in terms of much lower effort needed to run downhill (muscular damage notwithstanding). I’d say that this is just something that you need to be aware of when using power on your runs. If you’re looking to stick to an exact output number during a run over varied grades - I find it makes sense to go a little above your target watt number on the inclines, so you don’t have to pound out descents to hit your target average. But this tends to come naturally the more you get used to running with power.



For ultra running, there’s definitely periods where power hiking is a major component of both training and racing. When hiking steep grades, you will definitely see much lower power numbers in relation to running the same inclines, even if running very slowly. I found a very technical explanation of some of the complications of using power data for ultra runners here -


If you are so inclined, you can really get into the weeds of using power data there - much more so than I would be able to explain in this review. 


At a very basic summary level - for trail and especially ultra runners, you should expect to become familiar with different power values for flat running, inclines, descents, as well as power hiking. I do admit that it may seem daunting, but most runners have likely gotten used to doing the same evaluations already with other metrics, i.e. pace or heart rate.


Analysis of data:


Mike P: Critical Power is the main number which is calculated by the Stryd pod. From that number, similar to pace zones or heart rate zones, Stryd determines “Power Zones” for different running intensities. You can then use your power data on the run to guide your different types of training runs. For a detailed explanation of what it exactly is, reference Stryd’s website here -


Essentially, the point at which you reach your Critical Power wattage value, is the top of your threshold zone. This seemingly corresponds with the lactate threshold. If you look at my generated Power Duration Curve below, the 336 value corresponds to the 17:30 - 18:30 duration range. 


Your critical power value is calculated based on max effort runs over the past 90 days. If you check out the link above, you’ll see those determinant runs range from max effort sprints up to 40-60 minute efforts. Performing max effort runs over these varied ranges fills out the power curve model most accurately. This is a key point to understand - the determined CP and Power Zones ranges are not based on some magic formula or guesstimation - they are strictly based on your actual effort and actual completed runs.  



In my case, after receiving the pod, I had a 5K Turkey Trot lined up. The course ended up being short, but I ran 15:00 at 5:18/mi.  This was enough for Stryd to initially set my CP value to 336. My CP value actually hasn’t changed since then, as that was my highest output run closest to the CP duration range. I’ve annotated my curve above with the other key runs determining CP. The white line in the chart is the modeled curve, which Stryd calculates as your maximum achievable value across the duration range. 


Once again to clarify - it’s all based on your input data - if you run faster than your modeled value at any point on the duration curve - the curve will be adjusted accordingly. As you can see, I did a (nearly) 10K race which was close to the modeled curve - which was about accurate. It was a difficult course with a big hill and a dirt section. It was also 20F outside. My 60:00 tempo run was also expectedly lower, especially towards the lower end of the duration curve (~40:00). This was expected due to the fact that it was not a race scenario and I was focused on steady output for the entire 60:00. 


Michael E’s Analysis: I discussed briefly above how I use the pod, practically, but I will also lend my thoughts on Stryd’s PowerCenter and (what I find relevant) race approximations. Anyone with a Garmin watch will tell you how massively inaccurate the race predictors on that side can be (the day after running 2:22 in Chicago, I got an update that my updated prediction was 2:47 - thanks!), but Stryd is by far the most accurate race predictor I’ve found. It’s not perfect, but it is quite good - in a short build, I took another stab at sub-2:20 in Houston… the race was a miss for me (2:25), but Stryd had my prediction at 2:23:14, which would would have been similarly reasonable on that hot day. Even more telling - I didn’t wear the footpod at Chicago Marathon (was too late in changing shoes in the warmup area), and it predicted a 2:22:30 when I checked the app that day (I ran 2:22:18). In all cases, I would like to be a bit… faster, than what it’s predicting, but it’s orders of magnitude more accurate than Garmin, which is a really nice benefit (and a testament to the quality of data it collects).




RSS/TSS/TP Scoring


[42 day average line shown in white]


Mike P: Stryd charts a Running Stress Score (RSS) from your runs which can be monitored and tracked in their PowerCenter dashboard. It’s along the lines of TrainingPeaks’ TSS where you can monitor your progress and keep an eye out if you’re overdoing it in relation to your current training load. I didn’t pay attention to this too much, as I already use TrainingPeaks, which has the primary advantage of logging and tracking workouts across different disciplines. I’ve been doing a lot of indoor cycling, as well as uphill skiing, with this being the offseason, so I need to factor that into my training load. 


If you’re strictly a runner, or if you are interested in strictly tracking your running load only, the RSS data could be useful. Also if you’re not already using a more full featured platform for training, RSS may be more insightful than the typical Garmin or Strava metrics. I can’t comment on that though, as I don’t use those platforms for training/planning.

[My experimental Power score adjustments are in the far right column - this is only for the purposes of evaluating my workouts in TrainingPeaks, as well as analyzing how power data works across different types of runs]


I’m a data guy, so I did thorough testing and analysis of the Power data in relation to the output data that I typically rely on - pace and heart rate. I mentioned earlier that I’ve dialed in my TrainingPeaks TSS scoring for the combination of road and trail running that I do. Now having the Stryd power data, I created a spreadsheet (see above) charting pace/heart rate/power values from workouts of various types. 


I won’t bore you too much, but if you have any questions, feel free to fire away in the comments section! Basically I determined Power (Watts) to be a very accurate scoring gauge for my purposes. BUT - I had to create certain factors to adjust the training scores based on terrain and elevation. This is all in an effort to normalize scoring across different types of runs - road, trail, and treadmill. Keep in mind that the Stryd Power Zones are determined based on fast road running. So generally speaking, trail runs of similar effort produce lower power values than on the road. The goal for me is to get an accurate picture of my training - so I can accurately plan and analyze my training.


Joost: After Mike’s excellent explanation of all of the Powercenter features, I can only add what I use it for: mainly keeping track of my CP, and Running Stress Balance, in order to check if I’m not overcooking myself at any given point.


As a part of our testing, we also got a subscription so we could check out all the extra content you’re getting when you subscribe. I have access to some of it for being what Stryd calls a “Pioneer”, or a customer from day 1. I’m a coach myself, so I haven’t applied any of the training plans, but I checked out a couple without actually doing them and they’ve gotten a lot better over the last year or so. I also particularly like the workout collections where you can find all sorts of classic workouts like the Michigan, adapted to power based training.


One of the main features of power based training is actually letting go of distance and pace and doing your workouts for x amount of time at y percentage of your CP, but the collections have lots of “classic” distance based workouts and also a collection of treadmill based workouts, where you change the treadmill incline according to the step in the workout.


If you’re a Training Peaks or Final Surge user like myself, you can create your workouts on those platforms for yourself or your athletes and they will sync with Stryd twice daily (you can also force a push). You don’t need a subscription for this.


Impact Loading Rate, Lower Body Stress


Mike P: During my testing, Stryd introduced two new metrics. The purported goal was to quantify a level of stress directly on your body as opposed to overall training load stress. This does seem interesting at first glance, but ultimately I didn’t find it very useful. Impact Loading Rate is the value that is determined in real-time, which you can see in the chart of each run’s data. Those values are put together, similarly to RSS, to come up with a Lower Body Stress score (LBS) which you can see in the chart below. 


I found that in my training, it doesn’t look much different than the RSS chart - in fact they are roughly the same. There are minor differences in cases where I did runs with a lot of descent, which is to be expected. But that’s the point - I expect if I run a lot of downhills, my “lower body stress” would be higher. I just don’t see how it’s telling me anything I don’t already know.


[Lower Body Stress is a new feature - no 42 day average yet]



Below you can see a snippet from a run with some climbs and descents - with only the Impact Loading Rate graph enabled. You can see the spikes during downhills. Duh, this isn’t really telling me much. Downhills = more impact. I supposed you can keep track of this if you wanted to dial back impact during a pre-race period, but again, this is something you’d naturally do anyway.




Other calculated data


Mike P: There’s a laundry list of metrics that the Stryd pod calculates - it’s really a lot of stuff for such a tiny device!  These include: Pace, Distance, Time, Elevation, Cadence, Form Power, Ground Contact Time, Leg Spring Stiffness, Vertical Oscillation, Air Power, and the above mentioned Impact Loading Rate. Some of these you probably have a general idea about, and I find most of them to be a bit esoteric, at least in terms of using them in any capacity as a guide. If you’re interested, there’s a very good and detailed explanation here.


Most of the metrics are just that - metrics, nothing you can really change. I suppose if you were new to running and/or somehow transitioning from very deficient to efficient running form, you may see some notable change in values, but I don’t think there’s much to really pay attention to for 99% of users. 


Subscription features - training plans, preset workouts


Mike P: This is an area that I didn’t really delve into much. I manage my own training plan and have everything set up already in TrainingPeaks.  I tend to set a general planned schedule ahead of key races in my TP calendar. Since I use a Garmin watch, I set up the specifics of any particular workouts in Garmin. I don’t think that introducing another platform into the equation would be beneficial for me. But, if you’re just starting out with structured training plans and you’re new to using Power, it could definitely be a good place to start.


Stryd does offer full training plans as well as a library of different workouts. Those are features that you’re either interested in or not. I’ll just mention one issue that I came across (before Stryd provided us with test subscriptions). The set of non-paid workouts is very limited. When I was trying to test some treadmill hiking workouts (see more details on accounting for treadmill incline below), I discovered that there is no way to manually create even a basic custom workout without paying for the membership. I do think that’s a bit of a miss by Stryd. As you’ll see below - accounting for treadmill incline in Stryd is a bit cumbersome. I think there should at least be some way to create a preset workout and preset your inclines.


Issues/drawbacks/limitations


Wind (headwind)

Mike P: The pod does have a small port at the front of the pod which takes wind measurements. Supposedly it factors in headwind when generating the power output value (running the same pace into a headwind = more power than in calm conditions). There’s obvious limitations with this - location of the sensor on your foot, accounting for tailwind?, how much can really be measured in that tiny port?  From my observation, I did notice a slight wattage increase when running into a direct, steady headwind. But in crosswinds, or lighter wind situations, it doesn’t seem to affect much, or at least it’s a negligible amount. I guess I’d conclude that it does work to some extent, but there’s really only so much they can do without strapping a weathervane to your body.


Joost: The hole is very easy to obstruct on certain shoes, but otherwise works very well. The Stryd has been extensively tested and reviewed in wind tunnels, so I figure that within certain limitations (like Mike indicated: crosswinds etc.) it makes for an accurate reflection on actual increase in power output in windy conditions. Tonight at the track, there was a bit of wind, and during my warmup, the Stryd app on my Apple Watch alerted me right away that I was going over my set power limit for my warmup.


Treadmill running (accounting for incline)


Mike P: One notable difficulty is accounting for power when using incline on treadmills. The pod is not aware of incline when you are running on the treadmill, so you will see drastically lower power values if you use high inclines on the treadmill. This makes sense as you are not actually gaining any elevation as far as the pressure sensors are concerned. There are a few workarounds for this - either way you need to manually tell Stryd what the incline setting is. 


Option 1 is to record your workout via the Stryd app on your mobile device. You can use one of Styrd’s pre-programmed workouts for this, or you can create a custom workout (this option is available only with a subscription).  You can also start a manual workout and toggle the incline value on the phone as you go. This is of course not ideal as you have to set the incline both on the treadmill and the phone while you’re running. But it does the job of accounting for the incline and getting an accurate power reading.


Option 2 is to use the Stryd Workout app on your watch itself. It also allows the option to set the incline manually as you go, as well as follow Stryd-created workouts. I found this option not useful as I prefer to set up my workouts in Garmin and also to use all my regular workout data screens on my watch. But it can perhaps be useful if you’re doing a more open-ended workout - you can more easily set the incline directly on your watch and not worry about using a phone.


[Stryd mobile app - interface for manually recording a workout and inputting incline]


Ultimately I use Option 1 for my treadmill run/hike workouts. I usually do run-hike segments where I alternate the incline between 1% and 15-20%. I follow a preset Garmin workout on my watch as usual, but then I start up a manual workout in Stryd on my phone and input the incline as I change it during my workout. I can see the “real” power output in my phone, while my watch shows the incorrect (lower) value (incline unaccounted for). Note- if you want to integrate the correct power data into a unified workout file, you’ll need to use an external tool such as StravaTools to merge your workout files here. It’s quite a handy tool, and useful for other issues with activity files.


Michael E’s Treadmill Thoughts: I really rely on this little foot pod for pace and distance both outside on urban runs, and (extremely frequently, this winter) indoors on the treadmill. And here, I’m happy to report that Stryd is hyper accurate! Even uncalibrated (Stryd offers a calibration option, but doesn’t require it - and I rarely need it), the foot pod is within 5 seconds/mile of my treadmill pace, and often is 1:1 (consider, also, that treadmills traditionally run slightly slow - the belt will turn out the proscribed pace, but the runner’s footstrike can cause the belt to slow! One of many reasons I trust the foot pod and not the off-the-mill data. Plus, if you run on enough treadmills, you’ll notice that many are uncalibrated messes…) Regardless, the Stryd is a godsend for anyone who wants accurate, homogenous treadmill data.


But, the caveats are there, as Michael P points out. For one thing, I do wish there was a way to estimate treadmill income natively on the footpod. Presumably it could be calibrated to a 0% grade and estimate (even approximately) whether your treadmill is set at an inline or not using a gyroscope, but for whatever reason, Stryd does not allow that. You can follow either of the methods described above, but if you record natively on Garmin and use only the Stryd Zones data field, then you’re out of luck.


Joost’s Treadmill Thoughts: I haven’t run on a treadmill in a very long time, so I’d forgotten about the incline. Both Mike and Michael covered it very well. As far as I can remember, the main reason you don’t get an incline reading on the treadmill is because you’re not really going up, so there’s nothing for the altimeter (probably barometric) to record.


For Zwift users, there’s a little iOS app called RunCline which will allow you to either manually set incline on the app while running or controlling some modern treadmill’s inclination automatically when you change it in the app or program a workout with incline information included. It will also read your heart rate from your Apple Watch and transmit all of this information to Zwift.


Battery life (for long ultras)

Mike P: I’ve heard the reports of the battery life to be in the range of 15 to 20 hours or so. This wouldn’t be enough to cover some very long ultra races. But, on the flip side, you could effectively extend the battery life of your watch by lowering GPS sampling rate (or turning it off entirely) - since the Stryd pod more accurately measures distance and elevation. This of course assumes that you don’t need navigation and don’t care too much about having an accurate map of your run after completion. But it is an option.


Physical pod must be exposed (for elevation?)

Mike P: Another minor issue, relevant to trail runners - the pod itself needs to be exposed to the air to get the most accurate data. There’s an actual opening for the wind at the front of the device, and pressure readings for elevation changes would likely be most accurate when exposed. This could be an issue if you use a gaiter, which I typically do for racing. 


Garmin IQ data integration - using workouts seems to trip up summary data

Mike P: Unfortunately, the integration with Garmin does not seem to be fully ironed out. I can’t say if other devices have better integration, but I’m a long-time Garmin user, so I’ll describe the issue here. As previously mentioned, I often use preset Garmin workouts which allows me to easily see summary data for workouts. This is helpful to easily analyze main sections of workouts, as well as averaging out data from interval reps separated by recovery sections.


I find that when I use Garmin workouts, the summary data that shows up in Garmin Connect is not displayed properly. First, for comparison- a regular (non-workout) run:


[Regular road run - summary data in Stryd PowerCenter. Notice Power average for each split]


[Same run as the previous screenshot (manual splits, not a preset workout).  In Garmin Connect - lap average data is shown, but curiously, there is no way to see the total watt average (212W) ?!?! ]


The following screenshots are from a Tempo workout where I set up a workout in Garmin which I follow on my watch. I typically use workouts for all of my runs, even easy runs. This way I can easily see summary averages for the main portion of my run, omitting the warmup and cooldown periods. The Stryd data is clearly and accurately measured and displayed in the graphs.



[Simple workout created in Garmin - broke up a 60:00 tempo into 15:00 periods. See the main highlighted line in yellow where I get accurate summary data for other metrics - time, distance, pace, HR, etc.]

Scrolling to the right to the far end of the same table - power data for the main workout laps is not displayed ??? Even the other laps are not accurate ?!  For the highlighted summary line (yellow), I see a value of 233W which is way off. The correct value was 297W - which I determined by highlighting the section in TrainingPeaks (or I could manually average the lap values - in either TP or Stryd PowerCenter)


There is literally no way in Garmin to determine the power values for those 15:00 laps. Furthermore, the power average for the entire workout (269W) is not displayed anywhere. This is very annoying for post-analysis because I have all other metrics summarized in one line except for watts. If I want to figure out an average watt value across different sections of a workout -  I need to break out a spreadsheet or calculator and figure it out manually. I’m not sure if this is a Garmin or Stryd issue, but until resolved, it’s definitely a big annoyance. 

[Same run in Stryd PowerCenter - I can clearly see power values for each manual lap, although I don’t have a summary value for the 4 x 15:00 sections.  That is why I use the Garmin workouts (for pace/HR). In this case it’s simple to add up watts and divide by 4, but in many other cases the lapped sections are different lengths so not easy to figure without a spreadsheet and some formulas. The total average power is also displayed at the top.]


Michael E’s Primary Use Cases: So, we’ll cover this in detail here, but fundamentally Stryd is a power meter for running. In the past couple years, Stryd introduced wind resistance calculation, so now your output even includes the headwind you were up against. It’s a super nifty inclusion, and can help justify (and support) hard efforts when the “pure” running pace doesn’t tell the whole story.


There’s also the distance and pace tracking, and for me (somewhat sheepishly), that’s the more important side of the coin. While I do analyze my workouts in Stryd PowerCenter (and will discuss that more herein), the power number is only accurate insofar as you use it to set training, which I tend not to do (and instead follow pre-set training and adjust based on effort, performance, etc. - a slightly more wholistic, if less technical, way of going about it). I do get superb use from Stryd as a footpod to track pace and distance, as discussed below.


Joost’s Primary Use Cases: This one is fairly easy. I use the Stryd on every single run I go on, except when I forget it or somehow ignore its blinking light reminding me to charge it. I’m not what you call a power junkie, meaning that from time to time, I will swap apps and use iSmoothRun with the Stryd and distance coming from GPS, but I’ve been using power as my main training metric for the last 2 years or so. The change came gradually but now I wouldn’t go back. Back in 2017, when I bought my first Stryd, I was still using a Garmin Fenix 3 for my running, but I’ve since changed to Apple Watches and have never really looked back. Whatever the watch itself lacked in the first couple of versions, Stryd made up for it.


Conclusions


Mike P: So you’re a runner, you likely have a GPS watch, and maybe you even have a really fancy full-featured GPS watch.  Maybe you pay attention to your pace zones when running, and maybe you also pay attention to heart rate zones as well. Maybe you're very analytical about your running and analyzing run data is your jam. Is the Stryd pod right for you? For wherever you fall in the above sections - I’d say, yes. Aside from those that are truly data-averse, the Stryd pod offers something for all runners.


At the most basic level, you get extremely accurate distance (and therefore pace) and elevation measurements. This is beneficial across the board, especially in conditions where GPS signal is not reliable as well as on the treadmill. Say goodbye to the days of standing around waiting for your watch to get signal. Say goodbye to wildly inaccurate treadmill readings. 


Taking it a step further - using power to guide your running and training is possibly a game changer. As described earlier, in so many ways it’s a much more reliable metric for many scenarios. As a trail runner primarily, I’d say it’s much more valuable on trails than on roads, especially if you are running in mixed grades. (I may be biased though) But on the other hand, if you do a lot of hilly road training, it could also be very useful for you.


I will absolutely continue to use the Stryd pod for all of my runs. I’ve been testing for a solid two months now, a period which has coincided with my off season (recovery into a bit of base building). I have a 50K race lined up shortly after this review will be published - I’m curious to dig into the data after that race as well as other longer ultras later in the year. I plan on doing a follow up long-term post later on with further observations based on a season of training as well as racing. 


Michael E: While I absolutely adore my Stryd, and have used it for nearly every single run over the past several years (the lone exceptions being when I’ve left it on its charger, or on another pair of shoes - or once, when I shipped a pair to Sam for his testing with the footpod still laced in!), I haven’t scratched the surface of what Stryd, as a software company, can do.


As Michael P. notes, a massive benefit of the foot pod - and enough reason to own one for yourself -  is the extremely accurate pace and distance measurements that Stryd collects. Whether you’re on the treadmill or running in an urban jungle, this data is so much cleaner and more usable than GPS that I would fully recommend the Stryd for it alone.


In recent years, it’s clear that Stryd has shifted towards being a software company - they’ve moved to a subscription model, they offer training plans, and in-depth data analysis on their app and PowerCenter portal through the browser. 


For that to really be worth your monthly cost, it just comes down to what sort of runner you are, and what you value. If you’re a new runner who loves geeky data, or someone who has been stagnating a bit and want a new approach to improvement, I think the information you can access with Stryd is a no brainer. Even if you give it a go for a month, or 6 months, you can find value in the information provided. But, if you’re like me, and a little set in your ways, it’s not immediately clear that this new “Next Gen” unit is massively better than the old. It’s faster, for sure, and more accurate - but if you do the boring stuff I do, and you have a Stryd with a wind unit, you’re probably just fine with keeping it. 


But! If you want to venture out into Stryd-land, enter the universe of running power and data analysis, then Stryd is my favorite tool to do it. It’s a great company, with great hardware, and customer support to back it up. One thing I love about Stryd is how many different use cases there are - sprinters, track/collegiate runners, marathoners, and ultramarathoners can all approach it and get different value. It’s a terrific little device, and I can’t recommend it enough.


Joost: I remember reading at the end of the Fellrnr post about the Stryd that it was one of the single pieces of equipment he would immediately replace when lost. I feel exactly the same way. My experience with the hardware, the software, the company and especially their support has been exceptional.


Is it worth upgrading if you have a Stryd wind? Unless you see an immediate use in the new metrics and want faster reaction speed for shorter intervals, the answer is probably not really. If you have a pre-wind Stryd, it’s basically a no-brainer. You get the wind reading, sturdier hardware and the new metrics, which might become more useful in the future, as Stryd gathers more data from its users.


If you’re not a Stryd user yet and have been on the fence, I would say go for it. Like me, you don’t have to become a power junkie overnight, but use it for its incredible consistency and a new way of looking at your training. Power has sparked a revolution in cycling. It might help you become a better runner as well.


The Next Gen Stryd is available now from Styrd HERE


Samples were provided at no charge for review purposes. RoadTrail Run has affiliate partnerships (but not with Stryd) and may earn commission on products purchased via shopping links in this article. These partnerships do not influence our editorial content. The opinions herein are entirely the authors'.


Tester Profiles


Mike Postaski currently focuses on long mountainous ultras - anywhere from 50K up to his favorite - 100M. 5'10", 138 lbs, midfoot/forefoot striker - he typically averages 70 mpw (mostly on trails), ramping up to nearly 100 mpw during race buildups. A recent 2:39 road marathoner, his easy running pace ranges from 7:30 - 9:00/mi. In 2022 Mike won both the Standhope 100M and IMTUF 100M trail ultras within a 7 week period - both extremely rugged Idaho mountain races. 


Joost is a Belgian in his 50s living in Luanda, Angola, Africa, where he faces the heat, humidity and general chaos to run anything between 60-100 miles per week. He’s on a mission to win in his age group in the 6 marathon majors and has completed half of his project, with a 2:26:10 PB in Berlin in 2019 at 51. He recently won his M50 AG at the 2022 Chicago Marathon in 2:29. He ran in primary school, but then thought it would be a lot cooler to be a guitar player in a hard rock band, only picking up running again in 2012, gradually improving his results. Please check out Joost's coaching service here


Michael is a patent attorney and graduate of Northwestern University Law School. Prior to law school, he competed collegiately at Washington University in St. Louis (10,000m PR of 30:21). Michael’s PRs include a 67:43 half-marathon (Chicago Half-Marathon) and 2:22:18 marathon from the 2022 Chicago Marathon. Michael continues to race on the roads, and is chasing a sub-2:20 marathon and potential OTQ in the future.

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12 comments:

Brian C said...

As a Stryd user since 2017, this is a very good summary of it's best and worst attributes. I too recall that Fellrnr post about if he lost his Stryd he would immeidately replace it (as a trusted source, this was a big factor in my decision to get one - unrelated, what happened to Fellrnr? His site has gone dark for awhile)

Anyway, I also share the frustrations with integration with Garmin and I strongly get the impression that the Stryd developers are actively hamstrung by Garmin in what they will "allow" in their give/take - no coincidence that Garmin has their own Power model/tool.

Anyway, one of my biggest frustrations with my Stryd is when running at incline on the treadmill. I use the Garmin CIQ Stryd workout app, which allows you to set the incline manually (lots of button pushes when you go up to 15%), but I have longed for a better alternative to this. The Runcline app is intriguing and I had never heard of it until this post (probably because I am not a regular Zwift user). Could one of you guys share some more on how this works? I see that it's sending incline/pace information into Zwift - is it also helping Stryd properly calculate watts based on the incline as well? That would be a game changer for me if so. Really would appreciate some info on this, thanks.

Mike P said...

Brian C - Yes, I agree.. basically a lot of button pushes.

I'm not familiar with either Runcline or Zwift so I'll leave it to the others for any follow up. But I'm not sure if they do as much uphill TM training.

My TM run/hikes tend to be pretty regimented, so I can make it work if I set up a workout in Stryd beforehand. Then it's just a matter of starting my watch and the workout on the phone at the same time. But unfortunately you have to pay to customize a workout - I'm not sure if it's worth it for that feature alone.

Carsten said...

Sorry guys, but I don't think this review is up to your usual standards. There are some scientific "alternate facts" in here which makes the engineer in me just cringe.

First of all, power is not "a measure of the force you output in a predetermined measure of time". Power is energy/time (alternatively work/time), with energy(work) being force times distance. So power is force-times-distance over time. I guess it's easy to see how in a running context that is different from just force over time.

Secondly, you write (even emphasised), that "This is a key point to understand - the determined CP and Power Zones ranges are not based on some magic formula or guesstimation - they are strictly based on your actual effort and actual completed runs.". This is a complete misconception of how Stryd and other advanced power metric evaluation tools like Golden Cheetah or WKO5 use your actual, completed max efforts to define the critical power and the power zones. These efforts are used as input data to a mathematical model, namely the power duration curve which you also mention in your review. Your CP and the zones will then be derived from this curve (i.e. mathematical model). Your max. efforts are extremely important as input data to the model but in the end there is a "magic formula" at work here. And that's good, because it is much more robust and accurate way then to derive thresholds from individual single efforts.

Depending on the mathematical model this also means that your power output for a max effort at a certain time can indeed be higher than the resulting curve for that time if this is what gives the best fit overall. To be fair, I think Stryd is using a model which tries to avoid this situation most of the time, probably not to confuse the user. But it can happen. Analysing Stryd data in WKO5, which imho has a more accurate power duration curve model than Stryd, it's very common to have some of your max efforts being higher than the curve.

Mike P said...

Carsten- Appreciate the insights, but I think the idea with this review was to lean more on the side of practical insights as opposed to in-depth scientific analysis.

Most readers are interested in the idea of power as a metric, and whether or not it is useful as a training tool. Less so in the nuts and bolts of how the power curve is actually calculated behind the scenes. My statement was made to give the general idea that you shouldn't expect to have an accurate curve based on easy or moderate level efforts. More true max effort inputs = better curve modeling.

There are extremely in-depth research materials out there, beyond the depth of our review, if readers do wish to dig deeper.

Unknown said...

Thanks for this thorough review. I have been using the Stryd for one year on all my runs. Race predictions for road have become very reliable, I concur. One thing I realize is that I do not look at the power acore that much when I run… even though it is displayed. I tend to look at the peaks achieved AFTER a run… so I am missing on something. Has any of you been able to set Power-based alarms on a Garmin watch? I have the Forerunner 245 and it’s plenty of a watch for my needs as my runs rarely go beyond 12-14 miles.

Mike P said...

Unknown- I was going to guess no since Garmin integration doesn't seem to be that great (from the Garmin side it seems). I did a quick search and confirmed-

https://support.stryd.com/hc/en-us/articles/360010808494-Can-I-set-power-alerts-on-my-Garmin-watch-#:~:text=Currently%2C%20it%20is%20not%20possible,indication%20of%20your%20power%20zone.

It's a non-native metric, that's probably the reason.

Interesting that you haven't used it on the run. Seems like you have enough data already, so you should be able to zone in on a power range and try to target that range for some runs. Maybe give it a shot and see how it goes. I'd say it's very helpful for hilly runs, and Joost uses for speedwork.

Anonymous said...

Power-based alarms are available with the Stryd Workout app on Garmin watches. However, Garmin messed something up in the latest firmwares for some of its watches which results in Garmin native power being additionally written into the fit file when you use the Stryd Workout app. You will still Stryd’s data inside the Stryd Powercentre but other sites like Garmin, Strava or TrainingPeaks might show the Garmin power. Not sure if the 245 is affected by this bug.

Personally, I just use regular Garmin workouts for power. I add the target power as a note in the workout. This is then shown on the watch while I run so I can see where I should be. I am not getting any audio queues but I think that these anyway make you lazy. I think it’s better to work on getting a feeling for how certain target powers should feel. So I just have a look at the power shown by the watch every once in a while during a workout. There is just too much which can go wrong with audio cues that I miss them. That being said, as mentioned, if they are your thing, use the Stryd Workout app.

Brian C said...

Mike P - I had the opportunity to experiment with RunCline over the weekend and since it sounds like you do a lot of uphill incline treadmill work you should try it out! Amazingly it does everything we want from the Stryd iOS app:

Connect to HRM
Easily allow adjustment for incline up/down

And ALOT more:
Can connect to Smart Treadmills (or the NPE Runn) to automatically adjust the incline % in the app based on what the Treadmill says it is. Alternatively you can upload a GPX file and it will actually adjust the treadmill incline % to match that.
Can "push" your run metrics (pace, HR) to Zwift (on another device). I'm not much of a zwift user so I haven't tested this myself but I've seen it done.

I'm actually amazed at this little app and so glad I read about it in the review posted here.

Mike P said...

Anon - Yes, you are right - I didn't notice that. But I also don't use any metric alarms during my running, I just tend to spot check as well.

I did try the Stryd workout app on my Garmin this weekend and I didn't really like it. I adjusted the inline manually on my watch to match the TM, and the power seemed to be adjusted appropriately. But the total elevation data for the run was messed up. I did some small variations of elevation. My TM total was 183 ft, I got 3 ft in Garmin Connect, and 21 ft in Stryd PowerCenter ???? No idea what's going on there. For now I'm sticking with using the Stryd app on my phone (+ data merging via StravaTools).

Brian C- Runcline looks promising, I'll definitely try it out. I didn't see my TM on the compatibility list though. But if it could re-transmit the accurate incline-adjusted power data to my watch, that would eliminate the need to merge my data files after the run.

Brian C said...

Mike P - That's too bad about treadmill compatibility, but it will definitely pick up the manually-entered incline and re-calc Stryd power and then final file will not only have elevation-corrected power, but ALSO elevation gain and a graph showing it. It's really neat. And if you decide you want it to auto read incline, the NPE Runn is supposedly a good little gadget although I have no experience with it myself.

For the poster(s) asking about Power alerts, there are several CIQ datafields that will do this for you. The one I use is no longer being updated by its author but it does this based on manual entry OR designated workout steps. It's DR7c0 Datarun Premium by joop_verdoorn. Very nifty data field.

Chris said...

Take a look on the RunPowerWorkout datafield. It is great for running with power based structured workouts (I do sync mine with finalsurge). It gives you alerts if you are outside the right target and so on. :)

https://apps.garmin.com/en-US/apps/8c2fce29-0c7c-41f3-9a8f-5d3093c9cf2f

Mike P said...

Thanks for all the tips. I'm just scratching the surface as far as 3rd party apps and data fields, etc.