Is Meters/Stroke a Useful Metric?

[Xrayvizhen]

Newbie question: I recently noticed I can download a CSV file of my history and see that over the 8 weeks I’ve been in this new hobby of mine my times for 500m, 1k, 2k and 5k have all improved significantly, which is nice. (No time yet for 10k!) I also realized that if I divide distance covered by stroke count, the result will be a Meters/Stroke number…which is also improving. Is this any kind of significant metric to pay attention to and is anyone else doing this? I see there is no real correlation between the Avg. Watts and the Meters/Stroke number so I’m wondering if I should even bother tracking this, yet it seems it should be something to look at. If this IS something others pay attention to, I'm wondering what's a good number to shoot for?

[JaapvanE]

I pay attention to it, but probably not in a way you'd expect.

Meters per stroke tends to become shorter if you start accelerating (for example, look at the World Championship teams during their race). So it isn't an absolute measure. But it is an interesting nonetheless as it shows how effective each stroke is.

However, given a certain pace at a certain dragfactor, the "product" of strokerate and distance per stroke essentially is fixed. For me, recording these two metrics over time show when I get tired: my strokes tend to shorten up and I compensate by increasing the strokerate. Also, it is interestng to look at sessions with the same (steady state) pace and drag, and see if my stroke length tends to become longer.

[MPx]

I'm wondering what's a good number to shoot for?

10

Slightly tongue in cheek as IMO it would be different for everybody and different between (eg) an SS and TT session for most individuals, but I think 10m/stroke would almost universally be thought "OK". The other problem with it is that if you're targeting the number rather than just observing what it is (eg to achieve more meters per stroke) it can lead to unhelpful adaptations - like artificially lengthening the stroke by pulling up to your neck or similar and overly slowing the rate - none of which will help you go faster.

[Dangerscouse]

I also use 10 as a rough guide, but I don't pay attention to it, as it can be 13 or 14 on certain sessions, and the lower the stroke rate the more glide will be accounted for, which I don't think is always a good thing.

Happy to be proven wrong though

[edward.jamer]

Agreed with others. It's a useful metric while rowing since variation usually indicates that my form and/or pacing has shifted and might need attention... but generally seems less useful after the fact.

Number to shoot for depends on a bunch of factors... and may vary per person or workout. 10 sounds reasonable. I'm quite tall so usually aim just a bit higher per stroke, but it's more about the consistency than the raw value imo.

[btlifter]

A lot of folks who struggle to to improve what I would consider important metrics (pace) seem to find solace in "improving" other metrics, instead. So, to them, it's useful.

[jamesg]

Meters per stroke, as a metric, suffers from the same problem as Pace: the cube law that derives speed from Power as measured by the C2 erg, using W=kV³.

At training rates, 20 to 24, 10m/stroke implies 200 to 240m/min, which is 100 to 180W.

[MudSweatAndYears]

The meters/stroke metric suffers from being highly dependent on stroke rate: you can reach almost any desired meters/stroke figure just by dropping the rating. A much better metric therefore is energy/stroke (Wattage divided by stroke rate).

[Xrayvizhen]

Interesting responses. Thanks. When I first started, I was only around 6m/stroke. Based on advice received on this forum, I took a video of myself and saw my form needed some serious improvement, mainly at the end of the pull where my body was only at 12 o'clock. This surprised me greatly...I thought I was leaning back a great deal, but I wasn't. Therefore, I've been concentrating on trying to get to 1 o'clock, not as easy as you would think. My times are, in fact, improving and my m/strokes number is now around 9. Based on the responses here I'll shoot for 10 however, looking at times I see of others in my age group listed on the rankings page, I have a ways to go. Right now, I'm still shooting for "Average."

[Dangerscouse]

Interesting responses. Thanks. When I first started, I was only around 6m/stroke. Based on advice received on this forum, I took a video of myself and saw my form needed some serious improvement, mainly at the end of the pull where my body was only at 12 o'clock. This surprised me greatly...I thought I was leaning back a great deal, but I wasn't. Therefore, I've been concentrating on trying to get to 1 o'clock, not as easy as you would think. My times are, in fact, improving and my m/strokes number is now around 9. Based on the responses here I'll shoot for 10 however, looking at times I see of others in my age group listed on the rankings page, I have a ways to go. Right now, I'm still shooting for "Average."

That's a great example of how a message can be lost in translation.

Edging up to 10 metres per stroke is a good target, as it sounds like it will only improve your technique, but when you get more experienced I think it will become far less important.

[btlifter]

Interesting responses. Thanks. When I first started, I was only around 6m/stroke. Based on advice received on this forum, I took a video of myself and saw my form needed some serious improvement, mainly at the end of the pull where my body was only at 12 o'clock. This surprised me greatly...I thought I was leaning back a great deal, but I wasn't. Therefore, I've been concentrating on trying to get to 1 o'clock, not as easy as you would think. My times are, in fact, improving and my m/strokes number is now around 9. Based on the responses here I'll shoot for 10 however, looking at times I see of others in my age group listed on the rankings page, I have a ways to go. Right now, I'm still shooting for "Average."

That's a great example of how a message can be lost in translation.

Edging up to 10 metres per stroke is a good target, as it sounds like it will only improve your technique, but when you get more experienced I think it will become far less important.

Goodhart's Law seems appropriate here (and, in a lot of dimensions of erging performance):
"When a measure becomes a target, it ceases to be a good measure."

[Ombrax]

If you're into that sort of thing, in my opinion Watts / Stroke Rate is the best measure of "stroke quality." (to coin a new phrase)

There's been lots of discussion of it over the years, so I won't bother to repeat all that, but the bottom line is that you're measuring the amount of work done per stroke (technically Watts / SPM gives you Joules / stroke x 60) which is a real-life measure of what you're doing.

[Dangerscouse]

Goodhart's Law seems appropriate here (and, in a lot of dimensions of erging performance):
"When a measure becomes a target, it ceases to be a good measure."

I think there's a subtle difference in this instance. It's a target, but a loose target predicated on improving the technique.

When it's reached it will naturally fall away as something that is considered or it will keep increasing, rather than staying static as a 'target achieved'. I believe that Goodhart's Law is more concerned with it then remaining as the target, with no room for improvement.

[btlifter]

Goodhart's Law seems appropriate here (and, in a lot of dimensions of erging performance):
"When a measure becomes a target, it ceases to be a good measure."

I think there's a subtle difference in this instance. It's a target, but a loose target predicated on improving the technique.

When it's reached it will naturally fall away as something that is considered or it will keep increasing, rather than staying static as a 'target achieved'. I believe that Goodhart's Law is more concerned with it then remaining as the target, with no room for improvement.

I disagree, though I do acknowledge that I may be wise to defer interpretation on this one to a Brit.

But, economics notwithstanding, my point isn't to merely de-emphasize a particular, static, SPI. It's to totally dissuade anybody from looking at a correlational relationship, drawing inferences based on that relationship, and focusing any part of their training energy on "improving" that correlational data point.

[Dangerscouse]

I disagree, though I do acknowledge that I may be wise to defer interpretation on this one to a Brit.

But, economics notwithstanding, my point isn't to merely de-emphasize a particular, static, SPI. It's to totally dissuade anybody from looking at a correlational relationship, drawing inferences based on that relationship, and focusing any part of their training energy on "improving" that correlational data point.

As usual, you win. You've convinced me