Optimal drag factor vs demographics data?

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OarConsequences
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Optimal drag factor vs demographics data?

Post by OarConsequences » October 5th, 2012, 1:29 am

I have been looking for a good source of hard data on what drag factor works best (based on actual trials) for people along with their height, weight, and gender.

I've found guidelines such as C2's recommendations: http://concept2.co.uk/training/guide/damper_lever and a CrossFit article: http://board.crossfit.com/showthread.ph ... r+settings

Clearly, one size does not fit all. For instance, C2's recommended drag factor of 140 couldn't possibly be optimal for all 170 pound 5'6" rowers and 270 pound 6'6" rowers or even all 170 point 5'6" rowers for that matter. However, I'm sure that there are at least some loose correlations between height, weight, gender and the drag factor where they get the best times for a given piece. Does anyone know of a collection of data which plots demographics against drag factor? I know people might say that they like their drag factor to be at a certain number but I would like to see actual performance by the same person at different drag factors. It would seem that this data would *have to* exist somewhere given the amount of rowing data being generated and submitted to sites.

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Citroen
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Re: Optimal drag factor vs demographics data?

Post by Citroen » October 5th, 2012, 3:12 am

That's not what drag factor is for. Drag factor is there so you can configure your ergo to match the drag you're going to get in a boat. The variability is there so you can set up for a 2, 4 or 8.

Correlating for gender, height, weight isn't logical.

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Re: Optimal drag factor vs demographics data?

Post by OarConsequences » October 5th, 2012, 9:45 am

Regardless of the intent of damper setting, people certainly are not going to pull the same times with it set on 10 versus 5 versus 1, right? And according to C2's own guidelines, weight, height (presumably at least since their recommendations take age into account), and gender do play into the decision of where to set the damper.

I know that everyone is different and that there is no one magical drag factor that will be the best one for a given height/weight/gender. However, if you took thousands of people who row and had them each pull a 2K row at 10 different settings I would have a hard time believing that there are not clear peaks around certain drag factors for a given demographic ranges. I'm just trying to find if anyone has compiled that data already.

Cyclingman1
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Re: Optimal drag factor vs demographics data?

Post by Cyclingman1 » October 5th, 2012, 11:27 am

The subject of optimal drag factor has to be one of the most frustrating in this forum. I broached the subject in a discussion "Optimal Drag Factor" in Feb/2012. It seems like noone can really pin it down. One is almost left with "it does not matter." It is just choice. Of course, simplistically, it is just choice. But probably not in terms of best time.

I too would like to see plots of times versus drag factor for one person for a specific distance. Since 2K is the recognized race distance, I would like to see 2K times for drag factors starting at 100 with a step size of 10 for a series of persons. I agree that somewhere such data must exist. I suspect that the designers of the C2 rower many yrs ago would have had to investigate the true impact of drag factor.

While drag factor is not exactly like gearing on a bike, it has similarity. A bike rider would never say that gearing does not matter in terms of optimum time.
JimG, Gainesville, Ga, 78, 76", 205lb. PBs:
66-69: .5,1,2,5,6,10K: 1:30.8 3:14.1 6:40.7 17:34.0 21:18.1 36:21.7 30;60;HM: 8337 16237 1:20:25
70-78: .5,1,2,5,6,10K: 1:32.7 3:19.5 6:58.1 17:55.3 21:32.6 36:41.9 30;60;HM: 8214 15353 1:23:02.5

OarConsequences
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Re: Optimal drag factor vs demographics data?

Post by OarConsequences » October 5th, 2012, 11:39 am

@Cyclingman1
Exactly. At the very least, I would imagine that competitive rowers must have times recorded at different drag factors. How could they not? Would a rower looking to win the CRASH-B's not at least experiment with adjusting drag factor up or down in an attempt to pick up a few seconds?

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Re: Optimal drag factor vs demographics data?

Post by Citroen » October 5th, 2012, 12:11 pm

The problem you have is that lots of the folks rowing and ranking a) don't know what drag factor means, b) don't do anything other than slap the lever on 10 and c) don't get drag factor data record anywhere (it's not on the logcard). I like to row at DF 120 but if a machine shows anywhere between 115 and 123 I'll not bother fiddling to get it exact, I'm anal enough to check it every time.

So you could shout about it from the roof tops and only a small subset of rowers (the ones who are desperately anal about analysis of their numbers) would respond with a coherent drag factor number.

There are some suggested drag factor levels (on Concept2.com and Concept2.co.uk) but they are not prescriptive.

Hence why threads asking for a correlation are likely to die on the vine.

You could try posting on http://concept2.co.uk/forum where we have a larger population that haven't been sucked away to the poison of the Internet that is Facebook. But I suspect the results would be largely identical.

For competitive on the water rowers where the ergo is just their training tool they likely have a drag factor dictated by their coach. We've met folks at BIRC and the CRASH-Bs who are in category A (don't know what DF means) and category B (slap it on 10).

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Re: Optimal drag factor vs demographics data?

Post by Bob S. » October 5th, 2012, 12:26 pm

Since it is highly individual, the only meaningful demographics would be those that you do for yourself. It would take a lot of time and effort, but if you are really concerned about it, I would think that that would be the best way to get the information you want.

Another point to consider is the type of piece, i.e. short or long and high or low intensity. Anecdotal evidence suggests that short pieces (500m or less) call for higher drags than the longer ones. Again, it is very individual and YMMV.

Bob S.

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hjs
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Re: Optimal drag factor vs demographics data?

Post by hjs » October 5th, 2012, 3:49 pm

OarConsequences wrote:@Cyclingman1
Exactly. At the very least, I would imagine that competitive rowers must have times recorded at different drag factors. How could they not? Would a rower looking to win the CRASH-B's not at least experiment with adjusting drag factor up or down in an attempt to pick up a few seconds?
Good luck with your search, otw rowers often row at prescribed drag to mimic the boat stroke.
Erg rowers differ, using a wide range.
At races drag is not recorded, so not much dat there.

You could start a thread and ask people.

On thing is clear a strong rower is strong on every drag, and vice versa.

For sprints most people get better times with a higher drag.

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Re: Optimal drag factor vs demographics data?

Post by OarConsequences » October 5th, 2012, 3:58 pm

I acknowledge that there will not be a one size fits all solution to drag factor. I'm mostly just surprised that there isn't already a pool of data which plots drag factor against performance across various parameters like gender, height, and weight (I forgot include age in there as well). I would have thought that there would be more interest in that sort of data or at least interest in people doing it for themselves to see which setting gives the best time. Or maybe the drag factor makes no significant difference at all. Personally I think that is highly unlikely but if data exists that shows that to be the case I'd love to see that as well.

Thanks all who replied for the insight into this matter. I'll continue my search including on the UK board as Citroen suggested.

Cyclingman1
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Re: Optimal drag factor vs demographics data?

Post by Cyclingman1 » October 5th, 2012, 4:54 pm

I have been interested in this subject from the getgo in my rowing. I only started in Jan/2012. I was sidetracked this summer with illness, but I'm coming back. I haven't exactly made it a secret: I want to set the 65+, 2K record officially this yr. Did it once in Apr this yr with a C2Log time. Hence, I want maximum efficiency.

It does take a lot of time and subtracts from training to self-construct the data. I'm going to be forced to make some effort in this area. I have been using a lower settings than I once did, but have not found where I want to be.

Some things seem to be true. It is much harder to pull at damper 10 than damper 1. But one can generate far faster pace at damper 10. Also, it is far easier to get injured at high damper settings. However, there are definite limts as to how long in time that can be pulled. Hence, damper settings go down as distances increase. But that is all quite vague. SPM also come into play with drag factor and the fatigue associated with SPM.

I'm disappointed that Concept 2 does not have better info on the subject. Statements like "drag factor simulates water conditions" really do not help matters much. Most C2 users have never rowed a boat in their life - certainly not a scull.
JimG, Gainesville, Ga, 78, 76", 205lb. PBs:
66-69: .5,1,2,5,6,10K: 1:30.8 3:14.1 6:40.7 17:34.0 21:18.1 36:21.7 30;60;HM: 8337 16237 1:20:25
70-78: .5,1,2,5,6,10K: 1:32.7 3:19.5 6:58.1 17:55.3 21:32.6 36:41.9 30;60;HM: 8214 15353 1:23:02.5

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Carl Watts
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Re: Optimal drag factor vs demographics data?

Post by Carl Watts » October 5th, 2012, 8:43 pm

I think you will find there are just too many variables to even start to get the results.

Besided the obvious like height, age there is others like your fitness level and muscle types so there is no way your going to be able to tabulate the data as you cannot measure it. Even your rating or SPM is going to have an effect.

It comes down to you personally and you have to find out what DF gives you the best time.

Rowed for years on 164 DF and have now dropped it to about 136. I would make the sugestion that the Drag Factor is not so critical that +/-1 is going to radically alter your performance.

Specific short events like the 100M or the 500M aside, I would say +/-10 or even 20 will have little effect so it shouldn't take long to find the zone that suits you. Bear in mind that as your fitness changes and body composition changes it will have an effect so it's not a one off setting even for you.
Carl Watts.
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Concept 2 Monitor Service Technician & indoor rower.
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OarConsequences
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Re: Optimal drag factor vs demographics data?

Post by OarConsequences » October 5th, 2012, 11:03 pm

@Carl Watts
Thanks for your input. Yes, I would agree with what you said about body composition changing. I omitted age as a factor in my earlier posts but included it later as I think that is a factor. I would *assume* that there is a general curve of optimal drag factor which starts low for the very youngest rowers, peaks in the mid-twenties to early-thirties, then tapers back down after that. I don't know this to be true, it's just a guess. If the data were collected then we'd be able to scientifically confirm or deny that notion. I think it would also serve as a general guide for what someone's optimal drag factor could be based on various inputs, similar to how the VO2max calculations are done.

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Re: Optimal drag factor vs demographics data?

Post by jamesg » October 6th, 2012, 4:46 am

The work in a stroke is dependent on length and average handle force; for power add rating. We can select all these independently of drag; but only if the drag does not limit our choice. So we set a value that does not limit choice, and then do what we like.

This setting couldn't be simpler: set to zero and then increase if we can't catch the flywheel soon enough, always with a full length stroke so that the legs can do their work.

A mathematical analysis would need a vast amount of data and an N dimensional space to describe age, height, drag, watts, rating, length of workout, just to note the first few that come to mind. Neither exist in reality, and anyone capable of that sort of maths probably has his work cut out calculating trips to Mars for Nasa or suchlike. I'd guess some knowledge of Bayesian probability will be needed, as was used I hear during the Apollo missions.

To start the data collection, I'm 72, 188, 85kg, and did 21k at 2:20, rating 20, drag 90, HR mostly 140. I couldn't care less whether at a different drag I'd have gone faster or slower. 99% of time on the erg is training, not TTs, and when racing what counts is getting there first, not the time in itself.
08-1940, 183cm, 83kg. Last seen MHR 140.
2024: stroke 6 W-min @ 20-21. No times yet, now using WODs.

Cyclingman1
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Re: Optimal drag factor vs demographics data?

Post by Cyclingman1 » October 6th, 2012, 6:56 am

JamesG, you should clarify what it means to "catch the flywheel." The way I understand it the flywheel slows down less at lower damper settings, hence easier to catch. So starting at low damper settings and increasing if one cannnot catch the flywheel seems counterintuitive.
JimG, Gainesville, Ga, 78, 76", 205lb. PBs:
66-69: .5,1,2,5,6,10K: 1:30.8 3:14.1 6:40.7 17:34.0 21:18.1 36:21.7 30;60;HM: 8337 16237 1:20:25
70-78: .5,1,2,5,6,10K: 1:32.7 3:19.5 6:58.1 17:55.3 21:32.6 36:41.9 30;60;HM: 8214 15353 1:23:02.5

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hjs
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Re: Optimal drag factor vs demographics data?

Post by hjs » October 6th, 2012, 8:42 am

Cyclingman1 wrote:JamesG, you should clarify what it means to "catch the flywheel." The way I understand it the flywheel slows down less at lower damper settings, hence easier to catch. So starting at low damper settings and increasing if one cannnot catch the flywheel seems counterintuitive.
The other way around, a faster moving flywheel is more difficult to catch, this is the main reason people use a high drag for sprinting. Think of a bike, if you go downhill very fast, you have to use a very high spm to ad more speed to the bike, on a high gear that is easier.

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