Bodyfat and erg performance

[MRapp]

Our favorite hero likes to claim that fat has no affect (or is that effect?) on erg performance...it just hangs there in his words.

For the exercise physiology experts out there (this does not include aforementioned hero)...is this true? Everybody seems to agree that an athlete's VO2max is directly related to their erg scores. VO2max by definition is directly related to bodyfat. Milliliters of oxygen used per minute per kilo of bodyweight. An athlete that loses 10 pounds of fat while maintaining their conditioning and power has an increased VO2max.

If a 200 lb erg athlete loses 10 pounds of fat while maintaining their fitness and power, the new 190 lb athlete can still process the same amount of oxygen, but it has to be delivered to 10 pounds less body mass. It seems to me that just because an athlete is sliding up and down a rail, extra bodyfat still has a negative affect on performance.

This thread is not intended to discredit or dig at ranger, I do that enough in his thread, it's simply to get an accurate answer to a topic I've wondered about for a long time. Any thoughts?

[chgoss]

If you're less than lets say 25% body fat, it is going to take a bit more effort to drag extra weight up and down the slide, but not a huge amount, the more the weight, the more the additional effort. I'm sure a couple of the guys on the forum can cite the science behind figuring out exactly how much inertial work is involved.
If you get really "obese", and we're talking 25%+ body fat, then I would think the strain of that on your body might add another dimension and slow you down further than just the additional inertial work.


However, that extra weight brings with it a lot of power, that completely outweighs the negative affect.

There are weight classes for a reason, skinny guys have less muscle mass, less power (in general). That's why LW times are, on the erg, slower than the HW times in the same age category.

One can't say "well, I'm 175lbs, but since that 10lbs isnt helping me any, I should be able to call my times "LW" times, because after all fat doesnt make you faster"
To attempt to make that statement purposefully ignores the negative impact on your performance loosing that weight causes. Loosing 10lbs while maintaining conditioning and power is no joke.. it's really difficult.

IOW, fat might not help, but loosing it is sure going to hinder

[Carl Watts]

Gee thanks Chad ! 25% body fat is Obese ?

My scales put me at 25% currently but I think you will find Obese starts at at least 30 or 35% body fat. Please tell me this is the case quite quickly as I'm standing on the ledge of a very tall building ready to jump otherwise.....

I have to say that for me it would be hard to measure how it affects my performance. My logic would be sure I'm going to be faster if I loose 10Kg on the Erg, but on the other hand I would have to train and eat accordingly to loose the 10Kg and with the increased training of course I'm going to be faster anyway. Obviously you don't want the extra weight in a boat but on the Erg I suspect the extra has a minimal effect.

What I can say is if you switch to say running the extra weight makes a HUGE difference. The fat is nothing but a big handicap. Currently running a 2.4Km or 6 laps of a track in 12:26 and the extra 10Kg I'm carrying is killing my time.

[hjs]

Our favorite hero likes to claim that fat has no affect (or is that effect?) on erg performance...it just hangs there in his words.

For the exercise physiology experts out there (this does not include aforementioned hero)...is this true? Everybody seems to agree that an athlete's VO2max is directly related to their erg scores. VO2max by definition is directly related to bodyfat. Milliliters of oxygen used per minute per kilo of bodyweight. An athlete that loses 10 pounds of fat while maintaining their conditioning and power has an increased VO2max.

If a 200 lb erg athlete loses 10 pounds of fat while maintaining their fitness and power, the new 190 lb athlete can still process the same amount of oxygen, but it has to be delivered to 10 pounds less body mass. It seems to me that just because an athlete is sliding up and down a rail, extra bodyfat still has a negative affect on performance.

This thread is not intended to discredit or dig at ranger, I do that enough in his thread, it's simply to get an accurate answer to a topic I've wondered about for a long time. Any thoughts?

Of course it matters. fat will slow you down, it is just dead weight ergingwise seen.

But for people who are low in fat% and need to loose weight losing fat always comes with a penalty in also loosing protein/muscle, for them it works the othre way around.

But above let say roughly 12 % fat, lowering that percentage will always be an advantage. Less dead weight you have to carry up and down the rail. Otw the advantage will be bigger, less weight = less waterdrag = more speed

On longer distances also the heat factor comes in play, the longer the distance, more fat = more isolation = more sweating and that will cause the blood to function below optimal and slow you down.

You will not find a toprower with a high bodyfat percentage. Wonder why

[NavigationHazard]

You want a simple experiment suggesting the effect of extra body fat while erging, go get a 5-kg dumbbell and rest it in your lap while you row something. For a 100-kg rower the 5 kgs of extra dead weight in your lap would be analogous to an extra 5% body fat around your belly. I doubt very much that you'll be able to notice a difference.

The Physics of Rowing site offers a rough equation for estimating the energy cost of moving yourself up and down the slide: P = 2 U ( R / 60 ) = 4 m s^2 ( R / 60 )^3 where P = power, m is rower mass, s is slide length and R is rating. There are some problems with it (e.g. it assumes no recoil/bounce) but.... For purposes of argument let's assume a rower mass of 100 kg a slide length of 1 metre and a rating of 30. P = 4 * 100 * 1^2 * ((30/60)^3) = 50 watts. Now let's give the rower 5% more body fat: P = 4 * 105 * 1^2 * ((30/60)^3 = 52.5. That's a difference of 2.5 watts. For illustrative purposes that's the difference in watts between 2:00 pace and 2:00.5 pace.

[chgoss]

Gee thanks Chad ! 25% body fat is Obese ?
My scales put me at 25% currently but I think you will find Obese starts at at least 30 or 35% body fat. Please tell me this is the case quite quickly as I'm standing on the ledge of a very tall building ready to jump otherwise.....

Dont jump Carl!! there's people below, and you'll flatten them!! That area is already unstable geologically!!



couldnt resist, there's two sets of people I feel completely at liberty to make fun of (as I'm a charter member of both communities), those that are heavy, and those that are follicle challenged..

No idea what my body fat % is, "way to high" is probably close enough description.. I need to update my signature,, I havent seen 200 in years, I suspect it's closer to 215, although I tend to avoid scales....

[hjs]

You want a simple experiment suggesting the effect of extra body fat while erging, go get a 5-kg dumbbell and rest it in your lap while you row something. For a 100-kg rower the 5 kgs of extra dead weight in your lap would be analogous to an extra 5% body fat around your belly. I doubt very much that you'll be able to notice a difference.

The Physics of Rowing site offers a rough equation for estimating the energy cost of moving yourself up and down the slide: P = 2 U ( R / 60 ) = 4 m s^2 ( R / 60 )^3 where P = power, m is rower mass, s is slide length and R is rating. There are some problems with it (e.g. it assumes no recoil/bounce) but.... For purposes of argument let's assume a rower mass of 100 kg a slide length of 1 metre and a rating of 30. P = 4 * 100 * 1^2 * ((30/60)^3) = 50 watts. Now let's give the rower 5% more body fat: P = 4 * 105 * 1^2 * ((30/60)^3 = 52.5. That's a difference of 2.5 watts. For illustrative purposes that's the difference in watts between 2:00 pace and 2:00.5 pace.

A few pound won't make much of a differenc, but let's say someone who goes from 25% to 10/15%. Going from just eating what you can to an athletic appearence. The effect will be 2/3 a big as above


Apart from the effects on the slide there are others that come in play.

More fat will effect the stroke, it will be more difficult to compress.
Apart from the slide movements our body also makes vertical movements against gravity, the higher the weight the more that will become.
Weight around the belly and chest area will make breathing less easy and cost more energy
More weight/fat will make us heat up/sweat more, the longer the distance the more this effect will take it's toll

How big these effects are is difficult to say but it's without a doubt they do.

And apart from fat, extra weight in the form off non row related muscle will also have a negative affect, big shoulders, arms and pics will slow us down..

[Carl Watts]

Interesting arguments but I will still go for minimal effect, or should I say it's not really the most significant of factors unless your in the clinicall Obese category where by the fat begins to effect the biomechanics of the rowing itself and the other factors like the fat insulating the body all over rather than the typical fat storage areas and preventing the blood to cool. It's an interesting subject that someone should write a paper on !

Backing up my argument for me would be my rowing log from over a year ago using the 5K as an example my performance has improved 30% (according to the analysis in RowPro) while my percentage body fat has dropped 3%. IMO the Erg and swimming are in the same category, no significant effects of gravity to consider. Yes of course loosing the fat will improve my performance further if it has no effect on my existing muscle mass but it is well down the list in comparison to regular training, adequate sleep for recovery etc if you really want to see your performance improve.

Just working on your fitness will see you drop the fat anyway. Anyone know how accurate those bodyfat scales are anyway ? Maybe I should chuck them off a tall building instead !

[KevJGK]

Anyone know how accurate those bodyfat scales are anyway ?

My tanita scales usually say 21% or 22% - I understand they are supposed to be 60% accurate compared to 92% for callipers?

So I had my body fat measured at the gym with callipers.

It came out at 21.6% - so the scales are pretty well spot on.

The interesting thing was they didn't check my height or weight for the calliper checks.

[MRapp]

Paul's VO2max calculator tells me a 95kg athlete pulling 6:30 has a VO2 of 57.9. A 90kg athlete with the same time has VO2 of 61.1. 5.5% better for the lighter athlete. Working backward, if a 95 kg athlete lost 5 kg bodyfat without sacrificing any power, he should be able to pull the equivalent of a 95kg athlete with a 61.1 VO2, which would be 6:23.

I don't believe anybody addressed this piece of the equation. If so I apologize. But if an oxygen delivery system can deliver "X" liters of oxygen per minute, delivering that same level of oxygen to a smaller overall mass has to lead to improved performance even if there is no weight bearing such as in running. The simple energy of moving up and down the slide yields a very small improvement from the reduced weight, but I believe the oxygen delivery adds even more to the equation.

I am willing to admit this could be completely off base but it makes sense to me...any thoughts?

[chgoss]

Hmmm.. I'm not an exercise physiologist, but I'll pretend for the moment:

- reducing weight while retaining all of the power (measured by keeping the 2k the same) increases V02 max according to the calculation.
- But, by definition you didnt increase your erg score... it stayed the same, so it's taking a higher VO2max to produce the same erg time

the odd result is probably an artifact of the fact that muscle and fat dont burn O2 at the same rate?

[Nosmo]

VO2max by definition is directly related to bodyfat. Milliliters of oxygen used per minute per kilo of bodyweight.

There is also absolute VO2max, which is not normalized by body weight (it is just Milliliters of O2/min). Just saying VO2max is ambiguous without the units of other wise making it clear.
For erging absolute is a much better predictor of erg time.
In a boat the weight does come it to it but not nearly as much as in running of cycling. Top hwt rowers typically have very high absolute VO2max, much higher then runners or cyclist, but their normalized values are typically much lower.

Plug some numbers into the C2 VO2max calculator and you will see that the absolute VO2max is the correct predictor.

[Gus]

Wouldn't there be some additional energy expenditure to overcome the inertia of the additional weight you would carry as extra body fat? After all, you move it back and forth from a full stop at each end of the stroke.

[Bob S.]

Wouldn't there be some additional energy expenditure to overcome the inertia of the additional weight you would carry as extra body fat? After all, you move it back and forth from a full stop at each end of the stroke.

Navhaz covered that in depth on this thread already just a few hours ago.

Bob S.

[Nosmo]

Wouldn't there be some additional energy expenditure to overcome the inertia of the additional weight you would carry as extra body fat? After all, you move it back and forth from a full stop at each end of the stroke.

Navhaz covered that in depth on this thread already just a few hours ago.

Bob S.

Yes. and if you use his numbers (2:00 vs 2:00.5) in the calculator the change for a 75 kg erger would be 0.5 ml O2/min/kg. I'm sure this is well within the uncertaintly of the calculator.
As others have said the 5% body fat would also effect the cooling and the ability to compress if it is on the belly.

Being Fat does not help but it doesn't hurt nearly as much as it does in other sports.