Garmin Performance Condition and Strava Relative Effort

Preface by saying I work at Stryd but I think there’s a metric from Stryd’s platform that can be seen as comparable, called Running Stress Score.

Similar to TSS or training stress score from other platforms like TrainingPeaks. I don’t really even track mileage anymore, rather I track my daily or weekly RSS and follow the Running Stress Balance (difference between 7 day and 42 day RSS average) to monitor my training load.

I trained for years and years hitting round number mileage targets without really thinking what made up the mileage, and thinking that overall higher volume is the only answer. Changing the thought process (and even considering things like in your original post) can potentially help runners not focus on cranking up a one dimensional number which might lead to them being less injury prone or have a better time generally training.

CoachB wrote:

Seems like these are two pretty good indicators of whether a workout was about right or if it was too hard and if you can push your training a little more or if you should back off.

There are obviously factors in these two metrics that can skew your results, but assuming the conditions are the same from run to run, it seems like these are pretty accurate.

Thoughts?

These metrics are not 100% accurate. What is accurate is being honest with how your body feels, specifically your legs. You learn how to tell by experience.

outsider69 wrote:

These metrics are not 100% accurate. What is accurate is being honest with how your body feels, specifically your legs. You learn how to tell by experience.

Well, as a 49 year old guy with a history of injuries, I've appreciated the feedback. I understand they are not 100% accurate, but the additional warning signs / metrics are not

I finished a run on Saturday and I knew it was too hard. Upon review, my performance condition had dropped to -15 by the end of the run. I'm still not recovered from that effort. Couple that with the fact that it was at the end of 3 weeks where I was at the top of Strava's recommended range for weekly relative effort and it's pretty obvious why I'm still tight and uncomfortable on my runs 4 days later.

I rationalized pushing saturday's run so hard because this week was supposed to be a cut back week anyway, but it seems that the warning signs about pushing Saturday's run were there, literally in red numbers on Strava.

Chalk it up to experience.

You need to track the input (aka HR), without it, you only measure the output (which is possible to do using distance and intensity). No need for Stryd.

CoachB wrote:

Seems like these are two pretty good indicators of whether a workout was about right or if it was too hard

Thoughts?

Too hard?

Never heard of that workout.

If others like the aforementioned indicators, great.

I agree that the feedback is generally helpful. I think that a general rule of thumb that people don't tend to follow is that it's okay for hard days to be "too much" as long as the easy days are equivalently easy on the opposite end.

For instance, my easy days are anywhere from 7:40s if I'm feeling good and 8:30's if I'm feeling rough. The difference in heart rate at those paces is only about 5 bpm. It's just not worth it for 5 bpm more, and while I get that it will add up to something over time, the benefits of easy days will never touch the benefits of a hard day.

I think it's good you follow those metrics, I use them a bit myself. However, most of the metrics are too heavily influenced by heart rate.

I ran yesterday on ice. I was basically jogging 9:30 pace so I wouldn't fall. My heart rate spiked MASSIVELY when I was slipping around (up to 175 at times) I assume due to the adrenaline of narrowly escaping death. Because of the high heart rate reading, my garmin told me it would take 36 hours to recover from an easy 5 miler at 8:30 pace.

Performance condition is basically how much your efficiency (the thing that Garmin misleadingly calls VO2Max) differs from your own baseline.

Problem here is, your baseline is established mostly using your regular daily jogs and not workouts (simply because there's much more of those, or should be).

For things like alactic sprints, your performance condition will be greatly overestimated, because Garmin (FirstBeat, rather) thinks you are super efficient. In reality, it just ignores oxygen debt.

Same story for shorter intervals. Long intervals and continuous tempos you get overestimated less. Hill intervals, long hilly runs - underestimated.

Is it useful at all? Yes, it is. Assuming your VO2Max (Garmin's VO2Max) is established and relatively stable you can compare performance condition on similar runs, especially on non-workout runs. For a regular run, If it's significantly below zero, you're not recovered. If it's zero or above, time for a good workout (unless you're glycogen depleted, this can make you at the same time super efficient and feeling like sheet).

My Strava fitness score has an inverse correlation to my fitness? It seems to assume that running huge amounts of volume at incredibly high heart rates is a good for fitness. When I was just getting started, weighed 230+ pounds and was cranking at a ton of 8 minute miles with a high HR I was at like a 120 for awhile. Now... more like a 50 despite being 5 minutes faster in the 5k and objectively fitter.

Garmin seems to correlate well to my overall fitness when it is getting accurate HR data. For me it seems to under club my actual VDOT by 3-4 points but it does rise and drop based on present fitness in my experience.

Runalyze, with a correction factor, seems to get the closest to actually tracking my fitness in my experience.

highhoppingworm wrote:

My Strava fitness score has an inverse correlation to my fitness? It seems to assume that running huge amounts of volume at incredibly high heart rates is a good for fitness. When I was just getting started, weighed 230+ pounds and was cranking at a ton of 8 minute miles with a high HR I was at like a 120 for awhile. Now... more like a 50 despite being 5 minutes faster in the 5k and objectively fitter.

Garmin seems to correlate well to my overall fitness when it is getting accurate HR data. For me it seems to under club my actual VDOT by 3-4 points but it does rise and drop based on present fitness in my experience.

Runalyze, with a correction factor, seems to get the closest to actually tracking my fitness in my experience.

What kind of correction factor do you use in Runalyze? I use 0.94 now and it is equal what my garmin shows

.94 lands me pretty much spot on my 5k PR. Runalyze registers a 70-71 for me typically and my real VDOT is more like a 66.