Garmin Running Power – Pros & Cons

13 December 2017

Reading Time: 5 minutes

Garmin have just released a new app, “Garmin Running Power”…let’s call it GRP for short.

This post will provide a bit of background but then specifically discuss the pros and cons of GRP compared to the competitor products STRYD and RunScribe (there are others but I wouldn’t consider them yet if I were you).

Why Power?

Training or racing by PACE is great; but doesn’t work too well on hills. Training or racing by HR is great; but there is a lag in the reaction of your HR to your effort by about 30 seconds. Training or racing by RPE is great; but usually it’s only the better athletes who can do it well.

Power gets around all of these drawbacks and is a proxy for effort

Benefits of a Running Power Meter

There are exactly 14 benefits from a running power meter. Not 13 and certainly not 15 😉 This link from Coach and Author JIM VANCE is written for STRYD but the benefits equally apply to GRP.

14 Ways a Power Meter Can Make You a Faster Runner – Running with Power from STRYD

I was sceptical at first. However with over a year of use (of STRYD) I have definitely benefited (& that means I am 100% sure) from: pacing on an undulating HM (or 3); hitting intensity targets on hill reps; relieving the occasional monotony of training by using something else to pace to; getting differently motivated to hit power-duration PBs. The latter probably sounds a bit weird but once you get into POWER…it’s pretty cool to play with power duration curves.

PROs

It’s free. Everyone loves a freebie. My grandma always told me that ‘you get what you pay for‘ but I always thought she was a cynic, as lovable as she was.
If you are a current Garmin Connect user then GRP’s data just slots into your screen and post-race charts near-seamlessly. It just works. With no configuration as such. (See footpod for exception)
If you are an existing owner of a compatible watch it’s also reasonably likely you’ll own one of the required accessories (below)
Garmin provide 5 free apps which provide most of the key elements of usability. Meaning: power alerts, lap power, power zones
Uniquely GRP accounts for wind
Uniquely, you can choose to just display your data or display and save it. You might not want to save it as saving it could later ‘confuse’ other sports data systems you use where you also store BIKE power data.
A great, low risk way into running with power. Almost a ‘try-before-you-buy’ scenario if you were considering STRYD/RunScribe.
The required RD sensors each use long-life coin cell batteries. You won’t have to worry about having to charge up another sensor.
3rd party data analysis sites like Golden Cheetah, Training Peaks and SportTracks (MOBI) will be compliant to the data very quickly. SportTracks 3.1 desktop requires extra, annoying work with paid-for plugins but is compliant now.

RunPow STRYD RunScribe Comparison Review Features — .

CONs

GRP requires a compatible, high-end Garmin watch. Namely a Fenix 5 or Forerunner 935 (+Chronos). That’s the choice. In the future, it’s likely the Forerunner 645 will support GRP. Probably also a 74XT if released in 2018.
GRP requires Garmin Running Dynamics data (VO & GCT) from either a Garmin RD-POD or Garmin HRM-RUN/TRI.
Running Power is NOT properly native to the Garmin Running Environment. It CANNOT be used everywhere like, for example, pace or bike power or HR can. So there are NOT inbuilt RUNNING metrics for lap power, power alerts, power zones, averages and so on. NONE of that natively exists. BUT see above for the more than acceptable workarounds by using the various apps and the configuration options.
The WIND element of the GRP power calculation is suspect. It relies on offline weather forecast data recently downloaded from a smartphone – this is then derived from the compass heading on your watch. Generic weather for your locality clearly will not apply to areas of building or tree cover. Plus the forecast wind speed/direction is not always the same at true ground level. Advice: Disable wind adjustments.
The power calculation is made more accurate by more accurate PACE. By default it uses PACE from GPS or from GPS+GLONASS. Advice: Use a properly calibrated footpod as the source of pace (STRYD is best for accurate pace 😉 ). Otherwise you might face the ‘garbage-in’ ‘garbage-out’ scenario.
The power calculation relies on GCT and VO from one of the RD accessories previously mentioned. I suspect, but don’t know for sure, that VO/GCT will vary depending on the RD accessory you use. Just make sure you always use the same source.
If you use the RD-POD you may get different results from clipping it to differently elasticated garments around your waist. Meaning: wear the same shorts/tights/trousers. Readings may also vary with your changing muscle/fat makeup in that area.
Your data will likely NEVER be comparable to data from STRYD or RunScribe. So if you switch from GRP to RunScribe down the line then your GRP data will be of ZERO use to you. You will have to start again with your power zones and power-durations. Suggestion: Use GRP for a month, or so, and then evaluate how much you are using running with power. If running with power is of peripheral use to you then you have saved an expensive purchase of STRYD/RunScribe.
Data collection relies entirely on your watch. The 935/F5 have GREAT battery lives but if you don’t press go or run out of juice then no power is stored on the accessories (unlike STRYD and RunScribe)
Probably requires a correct and up-to-date weight & height values in your Garmin Connect profile…no more kidding yourself 😉

Summary

The Garmin Running Power apps really are cool. I like them. They are better implemented than the competition. However I have reservations about the power data itself. And that is a pretty big area to have reservations about.

If you already have the necessary kit then it is a ‘no brainer’ to try out GRP and see if you get any benefit from running with power – lots of people don’t; lots of people do !!.

I suspect the fall-out from the release of GRP will see that interested runners or casual runners will end up being the ones that use GRP on an ongoing basis. More serious runners/triathletes will probably end up using either RunScribe or STRYD.

All jokes aside about Garmin and their Wishy-Washy relationship with good programming, there are a plethora of issues I have with the running power info and how it obtains it. You covered those things already, but instant pace not coming from a footpod, the whole weather reporting and measurement, and frankly the measurement coming from the Strap and not from a pod.

All these sensors are approximations of course, but that’s a fairly vague/nebulous area to gauge. This could be either +/- a few points of precise or 30-100 points off. Both are approximations, yet i’d rather go with the one closer to approximation. I think most would.

I personally have little faith that the numbers coming back from Garmin’s measurements are anywhere near the actual. I also think it will never get close to the actual. Like most of the “features” from the company, they come out less as a fully recognized thing and more as a “work-in-progress beta.”

I’ll stick to my Stryd, it has consistently returned data that is consistent in all the metrics it reports.

tfk, the5krunner

Author

Reply to Justin

2 years ago

there is a calculation from STRYD somewhere demonstrating, i think , %metabolic efficiency which can be a max of 25% for super elite atheltes. that bascially ties back to stryd’s wattages delivering low 20’s %…give or take a bit. so higher number (grrmin) are measuring ‘something else’ other than the metabolic cost. but then again runscirbe is in the same ballpark as garmin.

‘covered these things’: not quite 😉 there is weight and height to go yet. former has an obvious effect, latter prob some cda related factor.

Webvan

2 years ago

Good analysis/summary, thanks. Being the owner of a 935, an HRM-Run (red pod) and a (Adidas!) footpod, it was indeed a no brainer to try GRP. I’m even finding the wind adjustment to be pretty effective with notable differences in numbers when running with and against the wind. Since I have both Power and Combo activated I’ll try activating wind for only one of them. The numbers seem rather high though based on the reported wattage of cyclists in the mountains but that doesn’t really matter.

The last of the 14 points for running with power (know when to increase your pace in a race) has me curious though. How can power be used for that? Does Stryd have a “total power used so far” field that would show you have a lot left in the tank based on past races?

tfk, the5krunner

Author

Reply to Webvan

2 years ago

you have target average power (determined by power duration) and you have variability (determined by target NP).
if your actual is lower you kow what to do.
at least that’s what i vaguely try to do when cycling (normally it’s slow down a bit though as i ‘forget’ i have to run afterwards 😉 )

Webvan

Reply to tfk, the5krunner

2 years ago

Thanks for getting back but I must be a bit slow on the uptake, sorry, NP stands for? On my original question, if you’re below you’re on schedule and your average power is lower than expected you can step on it? Too bad my HRM4 slipped during my 10k on Sunday as I could have used that as a reference!

On another note does Stryd show more variance than GRP when you step on it? I’m getting 370w a on verage during easy runs at 5:15/km with GRP and when I go full out around 3:15/km it only goes up to 500w…The full out value makes sense using data reported for cyclists on the Tour de France but then easy pace should be more like 250/275 it seems.

tfk, the5krunner

Author

Reply to Webvan

2 years ago

NP=no problems…or normalized power 😉 (a weighted average sort of based on the zones you are in) pick which seems the most apporpriate
if you are below average power, cycling, you can’t really just “step on it” perhaps a better one liner would be ‘push the constant effort level up a little’

variance to what?
– running power variance is low: the cp curve is MUCH flatter than a cycling CP curve. hence low variability in that sense (supported body weight)
– GRP power seems more variable than STRYD power. [[which may or may not be true (TBC)]] but i guess a decent moving average will smooth GRP out, so GRP could still be ‘right’

Webvan

Reply to tfk, the5krunner

2 years ago

Thanks, I guess amplitude would have been a better term. More amplitude would maybe help to stay in the target zone. With an easy effort coming in at 370 and all out at 500 there isn’t a lot of room. I’ll try “easier” as well as hills.

But there is no free wheeling when running so the watts are always going to be there, regardless of the pace.

Peter UBERTO

2 years ago

Have you determined what ballpark Average Power and rFTPw by using the 20 Minute STRYD test for different weighted runners over different Average Paces ? I have determined my Average power of 190-210 W and an FTP of 270 W. My original STRYD Chest pod measured an Average Power of around 600 Watts which was impossible for me at 160 pounds ( 73 KG). STRYD sent me a replacement foot Pod unit and my numbers were in the ballpark for a 9:36 Average Pace.
What I am getting at is how does your PWRavg and rFPTw compare when using Garmin compared to STRYD values. These values would then give runners their ballpark Average Power for different paces.
After looking at various running articles with Power, I was able to figure out what my ballpark ranges were as compared to 70-75 KG Runners during races. Like I said before, there was no way I could have an rFTPw over 300 unless I became more efficient and faster.
Peter

tfk, the5krunner

Author

Reply to Peter UBERTO

2 years ago

my stryd chest strap had similar but higher figures.
no i haven’t done the stryd tests and probaly won’t do them on garmin RP.

I MIGHT construct a CP curve with garmin RP. but, for me, that will require carrying 2-3 watches whilst doing near-maximal race effortS – which may well not happen in reality.

rFTPw>300…yes. i guess you state an unavoidable truth.

Peter UBERTO

Reply to tfk, the5krunner

2 years ago

You need to get some hi-tek firm to develop a smart ‘heads up’ display unit for serious runners and bikers. It would get too wet for swimmers… Ya, a rFTPw of 300 will never be in my ballpark.
Peter

tfk, the5krunner

Author

Reply to Peter UBERTO

2 years ago

they exist . 4iiii do one http://amzn.to/2CNvodx . there are several other companies too. I was supposed to be looking at a swimming one that beamed something into goggles but it never materialised.
you’ll definatly get a ftp of 300…jsut use the garmin version 😉