Stryd Data, Analysis, & Feedback
Below is a test I did with my Stryd unit using my Garmin 735xt. I would appreciate any comments or comparison data from others. I'm also interested in how are people who are using Garmin's setting up their screens with the data?
I have on screen 1
Timer, HR, Cadence, Power
Screen 2
Timer, Distance, Pace, Power
Screen 3
Timer, HR, Lap Stride Length, Power
STRYD TEST SET. Nov 6, 2017
4 x 1 mile on Track w/ 1 Min Rest after each mile (2 min after the 3rd fastest mile)
All running was done at 178 SPM using Garmin 735xt w/ Metronome set to buzz every 4th beat, and wrist based HR.
#1 @ 8:00 pace
Avg HR - 142 (Monitor read high for 1st half of the mile). Slower than my comfortable pace.
Avg Power 224
Ave Stride Length - 1.15
1:00 Rest
#2 @ 7:00 Pace (Felt very smooth and comfortable)
Avg HR - 132
Avg Power -256
Ave Stride Length - 1.33
1:00 Rest
#3 @ 6:00 Pace (6:07 actual time. 178 cadence was not quick enough for me to do a 6:00mile. Felt like I was over reaching with the stride. Probably Needed 180-182 cadence)
Avg HR - 154
Avg Power - 291
Ave Stride Length - 1.49
2:00 Rest
#4 @ 7:00 Pace. Again (wanted to see how different the data would be from #2 after the strong one)
Avg HR - 144
Avg Power - 259
Ave Stride Length - 1.33
Stride length and Power were very similar to #2. HR was 12 beats higher avg. Makes sense since I did an 8 min mile before the 1st 7:00 mile, and a 6:00 min mile before the 2nd one.
I'm thinking of doing this set again but run #1 @ 7:30 pace & #2 @ 6:30 pace, and then turn up the cadence to 182-184 and try for 5:45pace or faster. Then I should have good data for power, stride length, and cadence for every 30 seconds of mile pace from my top end to my easy distance pace.
I'd love to see some number from others and hear what test sets you have done and how you are applying it to training.
I'm going back down in distance from doing an IM this year and last to sprint and Olympic with an occasional Half Marathon or 70.3 race. Looking for ways to get my running faster again, but stay injury free. I did a lot of low intensity running over the last year mostly between 7-8 min per mile, but want to start racing again at 5:45-6:15pace for 5-10K distance.
Comments
I love using Styrd to regulate my running intensity. BTW, compared to using pace, my zone 1 and TRP are slower using power, but my zone 4 and 5 efforts are faster, than otherwise.
I don't overthink it. After an appropriate wu, I do an all-out 10 minute test. I divide the lap power of the test by 1.13, and that becomes my run-FTP. Coach P specifies zone 1 as an IF of 0.8, TRP as 0.8 - 0.82, zone 2 as an IF of 0.85 - 0.88, zone 3 as an IF of 0.9 - 0.95, zone 4 as an IF of 1.0 - 1.05, and zone 5 as an IF of 1.10.
I use a run calculator to turn the distance covered in the 10 minute test to set my treshold pace for calculating rTSS in WKO4.
I would be happy to elaborate as I realise not everyone is a Nerd.
As an aside I have WKO4 estimate my run FTP by substituting "runpower" for "bikepower" in a WKO4 report — but that is just me.
I'm an adult onset runner, didn't run a step until I was 49.75 y/o. But over the past two decades, I think I've developed a very finely honed internal sense of how my HR and pace correlate to my RPE, both during training at various speeds and during races, primarily triathlons, of varying lengths. But that took maybe 5-8 years to learn. It's possible, I think, that a power measurement could help shorten that learning curve for someone who is new to structured run training. And, it might also be helpful for "young" (which I define as anyone under the age of 27) runners who are dealing with a still changing physiology, a heightened sense of competition, and relative lack of discipline. Meaning it could keep them from blowing themselves up in any given workout, or in a race.
Now, for us OFs who've got a long athletic history (like you, I was a swimmer as a youth, age group 11-17, then college), it might be a different story. Two or three things jump to mind:
- Looking at my files which include power, I see the obvious fact that HR is a lagging indicator. When I start up a hill, my power changes instantly, the HR takes 10-30 sec to catch up.
- When I do long runs, unless I keep upping my RPE, my pace will slowly deteriorate after about 90 minutes, even if my HR is holding steady.
- Likewise in a race, a steady HR and RPE usually are associated with a deteriorating pace.
I suspect that the value of having run "power" available will lie in its use as a whip, to keep me more honest about the need to increase effort as a long training run or race progresses. Also, it should help me guard against poor performance (going too hard or too easy) up hills. I don't think its going to improve my ability to precisely target pace/effort during short (defined as 10 minutes or less) intervals during training.Once some really dedicated people play with the numbers enough, there may be an improvement in defining an rTSS for use in things like a Performance Management Chart. During @PatrickMcCrann 's podcast from Kona with the Stryd team, they speculated on possibly having a TSS target for an Ironman run, a number "not to exceed" to ensure cutting the fine line between blowing up and leaving something on the table. That seems some ways away, as it requires not only a reproducible and acceptable measure of rTSS, but also some way to factor in the effect of the bike: what was your bike TSS, VI, time, etc.
My Garmin (Fenix) screen #1 has Time/Power/HR/Cadence. I also have a lap screen which shows lap pace, current HR, current power, and current cadence. I set an interval beep to go off every mile, and, unless I over-ride it with a button push, I have it auto-lap every mile. Unless I'm doing track intervals, I really don't care about knowing my current pace. I'm more concerned with keeping my HR, cadence, and RPE where I want them. Now, I might start adding power to that, but the data is still too new for me to add it to my mental mix yet. There is a Connect IQ app which would make more than 4 data fields per screen available, but I'm afraid I couldn't see the numbers!
Stride speed and distance thread.
I’m bouncing between two threads that have great info. Can we merge these?
I have been using Stryd over 2 yrs first as their heart rate strap power meter version and now with the foot pod. I also was initially skeptical about is usefulness but the more I have used it the more I like it and use the data from it. There are many ways to get your zones. I would just run with it a lot and see what power correlates with what speed. I think once you get used to it you will see it can be used much like a power meter is used in cycling to gage effort you are putting out. The speed of course will depend on your efficiency and the course terrain and as we all know the heart rate is just a result of your effort and how your body is responding to that effort and the environment and your level of fatigue etc. I use Training Peaks and have my power zones set up and by doing that TP calculates rTSS based on power not on speed. I have used 5k best effort to set zones but also some all out short effort testing. I do go in and manually tweak my power zones at times to make sure the power zones align with my current pace training zones that I set up based on 5k or other threshold testing.
I also have a Garmin 735XT. I would not recommend using the wrist optical HR!!!! It is just not accurate enough yet. It will be right some of the time but too often I found it to give erroneous HR readings. Wrist strap has to be very tight. Temperature can affect it's ability to work as can skin type and thickness. Maybe it is just my skin but it was VERY unreliable for me.
I bounce between using 3sec power and lap average power. I would recommend using a mixture of both. That way you can see what speed changes or terrain changes do to power over the short term (using 3sec power) or see how pace and power interact---I do this by having watch set to measure average lap power and average lap pace on one screen and then set it to auto lap every 1/2 mile for a longer steady run. That way you can see the interaction of pace and power in another way.
Once I have the pod calibrated, I use it to measure speed/pace and you can get more reliable data and also good instant data vs. using GPS
I don't put things like stride length on a watch screen because I don't need to be trying to change that. That is just something that changes based on your speed and cadence and efficiency. I do look at it in analysis after the fact. I have used things like vertical occilation and left right balance on the watch when doing treadmill runs and if using that I will tape the watch to the front of the treadmill panel so it is easy to see all the time. I have also done that while watching power and pace and trying to make small changes in technique to improve power vs pace while on the treadmill.
I do l like to measure my Efficiency Index as outlined in Jim Vance's book. I will do this on a relatively flat loop course that I frequently run and see if I am improving my efficiency at typical race paces. I have been able to measure differences between various shoes that has been very consistent and repeatable
I would recommend getting and reading Jim Vance's book. Also the Stryd forum and facebook page has some good info. Steve Palladino on there has a lot of good info. It is a learning process but a fun tool to play with and I think very useful for pacing long efforts and races but also good for pacing fast interval much like using it to do Z4 or Z5 workouts on the bike.
BTW, the zones on the run are much closer together than they are on the bike
"EFFICIENCY INDEX (EI) Comparing NP and heart rate is helpful, but remember, we are more interested in maximizing speed per watt. Until now, there was no metric for this. Efficiency Index, or EI, is probably the best metric for monitoring the production of speed per watt. And what’s even better is that a runner can monitor this relationship while running. The calculation for this metric is simple, expressed as average pace or speed, in meters per minute, divided by average watts. EI = Avg Speed/ Avg Power Why use meters per minute for pace? In general, using meters per minute gives you a large numerator for the equation and thus gives you a more convenient calculation than minutes per mile or minutes per kilometer when divided by your watts reading. When you use meters per minute, it is likely that the figure will be close to the wattage number, making the product of the calculation close to 1.0. Remember that the higher the value of EI, the better, so having a baseline of 1.0 is highly convenient for seeing changes in EI. For example, let’s say an athlete can roughly 200 meters per minute, so the value of EI for this athlete is 1.0. If the athlete is later able to run 220 meters per minute at the same 200 watts, the new value is 1.10, an easily visible improvement in EI."
I do have a question.
Is there any way to find runs in Stryd that were done at certain paces and then compare those paces across a time period? I would like to chart over time my run power vs pace (for specific paces). That would allow me to see if I am becoming more efficient at all speeds, some speeds, or no speeds.
I just calculate it myself and keep track of it on steady state runs on flat to rolling course at similar speeds.
Here is an easy conversion tool. https://www.unitjuggler.com/convert-speed-from-mph-to-mmin.html
or you can just remember the conversion numbers and do it on any calculator.
I usually use the mph to meter/minute conversion that way I don't have to change the minutes per mile into a decimal. TP will tell me the speed of the run in mph also and the watts will be there. Just take your average mph for a steady run and convert it to meters per minute then divide that number by your average power. You should get a number likely less than one and the bigger the number(the closer you get to one) the better your efficiency. I have found that I am most efficient at tempo to threshold speeds and efficiency is less as I get slower or faster. Also you can use training peaks to "cut out" part of your run and just use that section for the calculation in the event you have a warmup with some walking or strides or a cooldown with similar. You want to use a steady state moderate paced run effort to do the calculation and if you want to see if you are getting better always use the same course at about the same speed to compare to. But you can calculate it for anything.
Example: yesterday I did a steady TRP run @ 8:02 which is 7.47mph using the converter tool that is 200.36 meters per minute. Now divide that by my average power of 262W and you get EI=0.765 (A bigger number is better and as you can see if my watts had been lower to go that speed then the number would have been bigger or closer to one)
I used to use my on metric of how many watts it took per mph I was running and I really like that better ( so I would say 262 watts divided by the 7.47 and get in this example 35.07Watts needed per MPH.) But Jim's EI is how most people talk about running power now and so that is what I use.
Also there is another parameter I think I remember they call it running effectiveness. You can google that. There is good info on the Stryd site and on their facebook site called stryd community. Good stuff from Steve Palladino and others
I'm curious what you mean by this. I'm working on my efficiency and trying to create new muscle memory. I have new shoes and will be watching wear pattern as extra feedback.
Does your cadence SPM change much from threshold compared to going slower? I'm finding that to have a quicker SPM I'm loosing extension or toe off is not as good.
I'm slowly getting thru Jim Vance's book.
Thanks!