Is there a 'good' weight band for watts/kg?

A light bike doesn't replace good fitness.

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Shrike
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by Shrike

Not sure how to word this. But say someone is like 120kg, or 35kg, I'm guessing the whole watts/kg thing won't work out for them even if they max out their power at their weight.

Roughly guessing being like 58 to 75kg is best depending on body type? Is there a chart perhaps :P

Sorry if that's badly worded. Trying to work out what to do with my body weight right now. Either drop it or keep it and just work on power from now on (I'm around 80 to 81kg, was going to go 78 which would be easy as I'm 15% bodyfat, but was thinking maybe I should go 75 if that wouldn't mean losing lots of power too).

Marin
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by Marin

If you're 15% fat then going to 75kg won't cost you power. If you lose the weight through riding reasonably hard, you'll actually gain power in the process.

by Weenie


Shrike
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by Shrike

I saw something that said losing weight is like 2/3 fat and 1/3 muscle, does that sound right to you? That's what kinda worried me actually..

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Rick
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by Rick

Watts per kilogram always "works". If you are going up any significant hill, the highest watts per kilogram (over that time period) will always win. It's a consequence of laws of physics.

But I suspect you are asking something like "If I lose weight will my W/kg go up, or should I gain muscle weight to get more watts than kilograms added?"

There is no definite answer to that question, since it is impossible to predict how much of weight gain will be muscle compared to other weight. But I strongly suspect that the answer for most people is that losing weight is the most efficient strategy. Look at all the top cyclists: the top pure climbers are Mahatma-Gandhi-style skinny, and even the "rouleurs" are pretty thin by comparison to average people. They only look "husky" because they are standing next to guys like Wiggans and Froome.

In my own experience, which might be just personal to me, my power goes up when I lose weight. I suspect that is because cycling power is one very specific output mode of the total body power. When I lose weight, there is less "other tissue" demanding oxygen and nutrients, and so that extra oxygen and nutrients that were previously unavailable to the cycling muscles are now able to be channeled into cycling, yielding more power at a lighter weight. But that's just my theory.

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ms6073
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by ms6073

Rick wrote:Watts per kilogram always "works". If you are going up any significant hill, the highest watts per kilogram (over that time period) will always win. It's a consequence of laws of physics.

Sometimes physics is not very user friendly when you consider that an FTP of 450 watts for a 75kg rider equates to 6 watt/kg on a climb, yet a 100 kg rider will have to develop 600 watts in order to keep up with the skinny rider. :wink:
Michael - The Anaerobic Threshold is neither...

ghisallo2003
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by ghisallo2003

See Joe Friel for same standardised Category power/weight numbers.

boots2000
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by boots2000

You want to maximize the ratio- regardless of weight.
All things being equal a heavier rider with the highest power to weight will have the most weapons because he will have the high absolute power too.
But that is all things being equal- they seldom are.

11.4
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by 11.4

Lots of questionable assumptions to consider.

Does watts/kg deliver actual speed that is linear at different body weights? Not really.

Does reducing weight increase power? Probably not. Your power may stay the same but your watts/kg goes up.

Does reducing weight decrease power? Probably not, at least as long as you are pursuing fitness while reducing weight. There are old, uninformed writers about weight loss and athletic fitness who would say that you lost muscle along with fat when losing overall body weight. That's only true if you simply sit on a sofa and starve. If you're working out, your body redirects calories, including from fat, to your muscles and by and large protects them from atrophy. And it pays to work on keeping your musculature constant or even increasing it a bit. Muscles consume much more resting energy than fat does, so the more muscles you have, the higher the amount of basal calorie consumption you do in a day. At the same eating level, those extra calories for muscles come from fat and you lose weight faster.

Why do grimpeurs get so skinny? They can actually reduce muscle bulk without reducing muscle strength or endurance, and they also find that at very low body fat and overall weight levels, they are served by reducing weight further (by reducing muscle mass). They don't have to offer the same kind of strength because they have to carry so much less.

Froome simply has the build he does and adding muscle bulk wouldn't increase his actual strength. He is a non-linear case and he does better simply minimizing weight as far as he can. He is NOT a model for most riders to emulate (as most pros have physiologies that no amateur can approach) so I wouldn't try to emulate him. You'll have to figure out for yourself, over time, what actually works best for you and where your optimum points are. Those are affected by age, training history, training intensity, body build and composition, metabolism, and a dozen other items. It's really not worth trying to look like Froome, any more than you'd want a girlfriend to try to look like Barbie.

kulivontot
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by kulivontot

This is a silly discussion. Your weight and watts are not correlated. Statistical distributions of human population may show a correlation between the two as you compare the height and athletic builds of various individuals. But to pretend that your wattage will increase as you eat cheeseburgers or that your power will drop if you go from 15% to 10% body fat is ridiculous. Drop weight and w/kg will go up. Always. Train more and w/kg will go up.
The real question you should be asking is "Should I be focusing on weight training for more muscle mass or on-the-bike training for upping FTP." That is a more valid discussion with many differing opinions. But worrying about losing too much mass that you'll lose power is pointless. As it turns out, the types of training that improve power output also tend to drop weight.

Shrike
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by Shrike

Thanks, that was really helpful actually, glad I asked even if it was in waffle form :P

Yeah, like 11.4 and a few of you guys deciphered, I was asking if watts/kg is linear across weights. So... yes in theory, but probably not in practise. Going to go for it then, drop the weight down but with lots of riding (was doing a fair bit of cal restriction there, like -300 a day for the past few weeks). Part of me wants to get better at things like sprinting so you know.. always felt like being a bit hefty helped with that even without that much training. But looking at sprinter weights now, many are under 80kg so..

pdlpsher1
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by pdlpsher1

I ride with a group of cyclists who are much heavier than me, and hence they also have higher absolute power. On the flats, downhills, and against a headwind they win over me hands down. On shallower climbs they are about even with me, with no apparent advantage nor disadvantage over me. And finally on steeper and longer climbs my superior power to weight ratio wins, and quite decisively too. With that being said I think I'd rather have a slightly different body build than my current build (62kg.). With a heavier build I'll have more absolute power which helps me on the flats/downhill/headwinds/gentle climbs, with only a slight disadvantage on the steeper climbs. I think between a 62kg and a 70kg rider, both of whom have identical watts/kg, I'd rather be the 70kg rider. Please don't ask me to bulk up to 70kg as I wouldn't have a bigger heart/lungs. When I say a different body build I meant a proportionally different body build with larger organs and longer limbs.

If you look at Tour de France winners you can see that a medium sized cyclist is the best, not necessarily the one with the highest watts/kg. So absolute power definitely comes into play as well as watts/kg.

kulivontot
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by kulivontot

I think cycling is about figuring out where your strengths and weaknesses are and exploiting it. You can train different power zones and alter your body composition to some degree but at some point you're just fighting your own genetics. Sometimes it's just better to pick certain events, courses or conditions that suit you.
That said, the vast majority of amateur cyclists are nowhere near this limit and will benefit greatly from "increase ftp, drop weight" by just upping training volume and adjusting diet. It's only when there physically aren't enough hours in the week to train that these sort of optimization questions come into play.

by Weenie


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