Modelling the determinants of 2000m rowing erg performance

[jliddil]

Modelling the determinants of 2000 m rowing ergometer performance: a proportional, curvilinear allometric approach
Scand J Med Sci Sports 2011: 21: 73–78

Previous studies have investigated the determinants of indoor rowing using correlations and linear regression.
However, the power demands of ergometer rowing are proportional to the cube of the flywheel’s (and boat’s) speed.
A rower’s speed, therefore, should be proportional to the cube root (0.33) of power expended. Hence, the purpose of
the present study was to explore the relationship between 2000 m indoor rowing speed and various measures of power
of 76 elite rowers using proportional, curvilinear allometric models. The best single predictor of 2000 m rowing erg-
ometer performance was power at VO2max (WVO2max )0.28, that explained R2 5 95.3% in rowing speed. The model
realistically describes the greater increment in power re-quired to improve a rower’s performance by the same
amount at higher speeds compared with that at slower speeds. Furthermore, the fitted exponent, 0.28 (95% con-
fidence interval 0.226–0.334) encompasses 0.33, supporting the assumption that rowing speed is proportional to the cube root of power expended. Despite an R2 5 95.3%, the initial model was unable to explain ‘‘sex’’ and ‘‘weight-class’’
differences in rowing performances. By incorporating anae-robic as well as aerobic determinants, the resulting curvi-
linear allometric model was common to all rowers,irrespective of sex and weight class.

[ThatMoos3Guy]

Really interesting looking study. Wish I had access to more than just the abstract. I'll have to hope that my school subscribes to that journal.

Jliddil, if you've read the whole article, do you have any further insights? What other measures do they correlate with success over 2000m?

[luckylindy]

The best single predictor of 2000 m rowing erg-
ometer performance was power at VO2max (WVO2max )0.28, that explained R2 5 95.3% in rowing speed.

...

Despite an R2 5 95.3%, the initial model was unable to explain ‘‘sex’’ and ‘‘weight-class’’
differences in rowing performances. By incorporating anae-robic as well as aerobic determinants, the resulting curvi-
linear allometric model was common to all rowers,irrespective of sex and weight class.

Gender differences are already reflected in VO2, so it makes sense that the model would throw out gender if a more specific variable is available. I wonder if they included height, and if so, what the R2 was for it.

[Leo Young]

Gender differences are already reflected in VO2, so it makes sense that the model would throw out gender if a more specific variable is available. I wonder if they included height, and if so, what the R2 was for it.

I believe its a major misconception that height is of any biomechanical avantage in rowing. Height is of no biomechanical advantage in indoor rowing and it is actually a biomechanical disadvantage in 'on the water' rowing ,due to the disadvantageous (overly acute and inefficicient) resultant oar angles, facilated by longer limbs.

The positive correlation between height and rowing endurance performace is primarily because of the positive correlation between height (more so than weight) and heart size and therefore potential maxVO2 (all other things being equal).

[DavidA]

Gender differences are already reflected in VO2, so it makes sense that the model would throw out gender if a more specific variable is available. I wonder if they included height, and if so, what the R2 was for it.

I believe its a major misconception that height is of any biomechanical avantage in rowing. Height is of no biomechanical advantage in indoor rowing and it is actually a biomechanical disadvantage in 'on the water' rowing ,due to the disadvantageous (overly acute and inefficicient) resultant oar angles, facilated by longer limbs.

The positive correlation between height and rowing endurance performace is primarily because of the positive correlation between height (more so than weight) and heart size and therefore potential maxVO2 (all other things being equal).

I would think that being taller might help as one would get more distance per stroke, and so could use a lower rate to go the same pace.

David

[luckylindy]

If height were a disadvantage, why would every single college rowing coach be out looking for tall recruits, and why would the rowing records be dominated by men over 6'4" and women close to 6', and why would erg records be dominated by the same group?

I've seen a couple extremely in-shape guys who were ~5'6" sit down on an erg and struggle to pull 2:00/500, while I've seen 6'6" overweight out of shape guys who struggle to walk up stairs sit down and pull 1:30/500. While this is anecdotal to an extent, all the records back up this relationship. Physical leverage seems to be much more at play than any differences in VO2max ... particularly since there are some tiny little guys with phenomenal VO2maxes that struggle with the erg (most great runners for example).

[Leo Young]

DavidA said "I would think that being taller might help as one would get more distance per stroke, and so could use a lower rate to go the same pace."

That's like saying people with longer legs should be able to run faster (unfortunately, something a lot of people actually believe).

If you're taller then stroke length is longer, but you can't rate as high, while if you're shorter, then stroke length is shorter, but is compensated for by a higher rating potential.

[Leo Young]

If height were a disadvantage, why would every single college rowing coach be out looking for tall recruits, and why would the rowing records be dominated by men over 6'4" and women close to 6', and why would erg records be dominated by the same group?

I've seen a couple extremely in-shape guys who were ~5'6" sit down on an erg and struggle to pull 2:00/500, while I've seen 6'6" overweight out of shape guys who struggle to walk up stairs sit down and pull 1:30/500. While this is anecdotal to an extent, all the records back up this relationship. Physical leverage seems to be much more at play than any differences in VO2max ... particularly since there are some tiny little guys with phenomenal VO2maxes that struggle with the erg (most great runners for example).

Plenty of short, heavily built, powerful guys can pull great sprint scores, but far fewer can acheive good middle and long distance scores, where absolute aerobic power (expressed in L/min, as opposed to relative areobic power expressed in ml/kg/min) is critical, due to lower potential for absolute aerobic capacity, because of their height.

However, if a short guy has a high absolute maxVO2, then he will be at no disadvantage on the erg against taller guys with the same absolute aerobic power (all other things being equal) and will potentially have an advantage on the water, due to more efficient oar angles.

Generally speaking though, shorter guys will tend to have lower absolute aerobic capacities. When it comes to rowing on the water, bigger engines more than compensate for less efficient oar angles.

[hjs]

If height were a disadvantage, why would every single college rowing coach be out looking for tall recruits, and why would the rowing records be dominated by men over 6'4" and women close to 6', and why would erg records be dominated by the same group?

I've seen a couple extremely in-shape guys who were ~5'6" sit down on an erg and struggle to pull 2:00/500, while I've seen 6'6" overweight out of shape guys who struggle to walk up stairs sit down and pull 1:30/500. While this is anecdotal to an extent, all the records back up this relationship. Physical leverage seems to be much more at play than any differences in VO2max ... particularly since there are some tiny little guys with phenomenal VO2maxes that struggle with the erg (most great runners for example).

a fit 5.6 guy will be small, so for him to be be better then a not so fit 6.6 is almost impossible.

Some one 5.6 would weigh maybe 65/70 kg, a 6.6 guy would easely weigh 110/120 kg. Even if we only look at lean mass the big guy will simply be a lot bigger. And so are his lungs and hart, so he almost alway will be better on an erg.

The point you are making over a 6.6 pulling 1.30 and be able to walk up a stairs are simply a bit nonsens, any erger who can pull 1.30 is fit. I talk about rowing a 2k, not a low pull of 1.30, that is indeed not worth much. Any slighty fit man can do that.

Great runners or cyclers struggle on the erg because their back and arms ar not strong, the weakest link determines how good you are at something.
Swimmers and longlaufers are often good at erging right away. There arms and backs are strong enough right away.

[DavidA]

DavidA said "I would think that being taller might help as one would get more distance per stroke, and so could use a lower rate to go the same pace."

That's like saying people with longer legs should be able to run faster (unfortunately, something a lot of people actually believe).

If you're taller then stroke length is longer, but you can't rate as high, while if you're shorter, then stroke length is shorter, but is compensated for by a higher rating potential.

That is why I said they could use a lower rate to go the same pace. If the taller erger uses the same rate wouldn't they go faster. (I would think that the taller erger loses less time switching directions, because the can go the same distance in fewer strokes.)

David

[Leo Young]

DavidA said "I would think that being taller might help as one would get more distance per stroke, and so could use a lower rate to go the same pace."

That's like saying people with longer legs should be able to run faster (unfortunately, something a lot of people actually believe).

If you're taller then stroke length is longer, but you can't rate as high, while if you're shorter, then stroke length is shorter, but is compensated for by a higher rating potential.

That is why I said they could use a lower rate to go the same pace. If the taller erger uses the same rate wouldn't they go faster. (I would think that the taller erger loses less time switching directions, because the can go the same distance in fewer strokes.)

David

At a lower rating, taller rowers might be switching direction less often, but they're going in the wrong direction for longer each stroke as well. How few strokes you can take to cover a cetain distance is totally irrelevant. A tall rower can achieve the same result rating higher or rowing shorter for that matter.

[cavanhagan]

Hi, interesting discussion for sure. My model is below, which uses "already known and easily measurable" predictors. R2 only 82.2% though, less than the stated model. Constantly trying to collect more data so please do fill in the survey.

https://cavanhagan.com/rowing-calculator

In terms of height, it is important to distinguish the difference between racing shell and ergometer. But on the erg, I would argue that height at as an independent variable would be better suited as the rower is able to overcome the slowing inertia of the flywheel at an earlier stage in the drive, and therefore more of the stroke would go towards speeding up the flywheel which in my mind should increase the "ease" of maintaining speed. I've just made all that up, but the correlation within my study for height with 2,000m ergometer time is -0.71. But as stated, is this just because it's correlated with weight? Potentially. Weight made up 8.6% of my model, and height was not included. Only issue is arm span was also included in the model, so I would argue that arms span was the main reason for the exclusion of height as it is almost the equivalent of height.

In terms of water time, height was correlated slightly less at -0.68, but that difference could just be natural variation- particularly since 2,000m time is nearly impossible to standardise.

Basically all the research I have looked at has shown height was strongly correlated with and predictive of 2,000m time and it's difficult to argue with that data. Why this is the case is difficult to explain, and probably would be better explained by someone in biomechanics and physics. There are some great papers on this area but I struggle to understand it all!

But if you are someone in the power to select crews, please be careful not to discriminate based on height. Technique and boat set up can be adjusted to tailor for shorter rowers. If a short rower is rowing in a boat set for a taller rower, their performance will be underestimated.