How much difference does weight loss make in the mountains?

[Bala Verde]

What if we reverse the assumption that weight loss - purely muscle mass, legs only - must induce power loss. Does weight gain - muscle mass, legs only - thus produce an increase in power?

If the latter were to hold true, wouldn't that mean that we would see more 'body builders' - in the leg area only - on bikes?

There must be some cut off point after which increase in muscle mass does not account for 'cycling efficient' increase in power (otherwise we would see more body builders?). However, wouldn't this then also work reversely, namely that, up to a certain point, muscle mass decrease does not account for loss in 'cycling efficient' power?

 

[rhubroma]

What if we reverse the assumption that weight loss - purely muscle mass, legs only - must induce power loss. Does weight gain - muscle mass, legs only - thus produce an increase in power?

If the latter were to hold true, wouldn't that mean that we would see more 'body builders' - in the leg area only - on bikes?

There must be some cut off point after which increase in muscle mass does not account for 'cycling efficient' increase in power (otherwise we would see more body builders?). However, wouldn't this then also work reversely, namely that, up to a certain point, muscle mass decrease does not account for loss in 'cycling efficient' power?

You say a lot of dumb things in a really intelligent way. Please don't take offense.

 

[Bala Verde]

You say a lot of dumb things in a really intelligent way. Please don't take offense.

I am just working with what is put forward in the thread. No offense taken

 

[rhubroma]

I am just working with what is put forward in the thread. No offense taken

Glad we cleared that up.

 

[egtalbot]

Interesting thread. Another way of looking at it is that if you drop 2 kilos and your absolute maximal oxygen uptake stays the same, then your relative VO2 max (the one usually discussed) increases. This won't have much impact in a very short climb, but it certainly will in anything over a few minutes.

Regarding local club riders and hills, it's definitely true that lighter riders don't have as much of an advantage on short hills. But as someone said, it's still all about power to weight ratio. It's just that power to weight ratio is not a three dimensional way of looking at it. You need to add the issue of how long one can sustain the power. It's not at all surprising that someone who can generate massive amounts of power can beat much lighter riders on a 1 minute long climb. I'm not saying that Hushovd could beat Contador on a 1 minute climb at 20% grade, but relatively speaking, he'd be closer than on a long climb.

The key is how long they can keep it up.

 

[riobonito92]

Here's my personal experience:

Every year I target a 5 day amateur stage race. This year I was 3 kg lighter than last year. I was 25 seconds slower than I expected to be in a 15km ITT but, for the first time in my life, I got the KOM points at the top of the biggest climb. I am accelerating better and can react much more quickly to changes in pace but my sprinting has definitely (and alarmingly) declined.

So for me, weight loss = less power but faster climbing. I think the loss of power was greater than I expected and not worth the sacrifice.

 

[Cobblestones]

Interesting thread. Another way of looking at it is that if you drop 2 kilos and your absolute maximal oxygen uptake stays the same, then your relative VO2 max (the one usually discussed) increases. This won't have much impact in a very short climb, but it certainly will in anything over a few minutes.

Regarding local club riders and hills, it's definitely true that lighter riders don't have as much of an advantage on short hills. But as someone said, it's still all about power to weight ratio. It's just that power to weight ratio is not a three dimensional way of looking at it. You need to add the issue of how long one can sustain the power. It's not at all surprising that someone who can generate massive amounts of power can beat much lighter riders on a 1 minute long climb. I'm not saying that Hushovd could beat Contador on a 1 minute climb at 20% grade, but relatively speaking, he'd be closer than on a long climb.

The key is how long they can keep it up.

Precisely.

The discussion should be about fraction of slow twitch and fast twitch fibers.

Everybody can put out 400++ W. Probably getting out of a chair will take that much power. Problem is, for most people, a short 400 W effort will be entirely anaerobe. That's why big riders go well over speedbumps.

 

[cyclingmad]

Precisely.

The discussion should be about fraction of slow twitch and fast twitch fibers.

Everybody can put out 400++ W. Probably getting out of a chair will take that much power. Problem is, for most people, a short 400 W effort will be entirely anaerobe. That's why big riders go well over speedbumps.

+1
Look at the size of riders doing well in prologues in the size of track riders. BTW Wiggins was 82Kg for Beijing which wasn't long after last years tour.
Look at the size of riders contending in the tour of flanders with 1k or less inclines up to 20% all big capable of anaerobic bursts. Long mountains are a totally different story

 

[usedtobefast]

i'll weigh in(pun). here in california we have real big mountains to ride on. as many as you want. there are a lot of very fit riders. they ones that go fast
uphill are pretty skinny. fit as hell too. climbing is cool, because then you get
to haul a-- downhill, which is a lot of fun imo.

 

[flicker]

Different kinds of hills. Short and steep: sprinters can power over rapidly.
If one is powerful and experienced they can fly over a bump say 800 vertical feet 3 or 4 times dropping light climbers. I call those hills bumps and include vertical climbs of 2200 ft. Part of it is how much pain one can sustain and of course understanding ones body and the mechanics of cycling.
On long grinding steep roads being extremely light is an extreme advantage.Such as AC, Schleck, Leipheimer, Cadel.

 

[egtalbot]

Different kinds of hills. Short and steep: sprinters can power over rapidly.
If one is powerful and experienced they can fly over a bump say 800 vertical feet 3 or 4 times dropping light climbers. I call those hills bumps and include vertical climbs of 2200 ft. Part of it is how much pain one can sustain and of course understanding ones body and the mechanics of cycling.
On long grinding steep roads being extremely light is an extreme advantage.Such as AC, Schleck, Leipheimer, Cadel.

Well, I'd put my money on a light climber like Contador or Schleck over a pure power guy any day on a hill 1200m long that climbs 800 vertical feet. Some of it also depends on othe factors that people have mentioned like ST/FT fibers - a pure sprinter probably doesn't have the muscle fibers to sustain the power longer than a minute or so. But that's quibbling about details - there is a point at which the power guys have an advantage.

 

[usedtobefast]

Well, I'd put my money on a light climber like Contador or Schleck over a pure power guy any day on a hill 1200m long that climbs 800 vertical feet. Some of it also depends on othe factors that people have mentioned like ST/FT fibers - a pure sprinter probably doesn't have the muscle fibers to sustain the power longer than a minute or so. But that's quibbling about details - there is a point at which the power guys have an advantage.

racing wise it is usually shorter steeper climbs they can kill you on. but if you can sprint yourself...power to weight ratio takes over.

 

[egtalbot]

racing wise it is usually shorter steeper climbs they can kill you on. but if you can sprint yourself...power to weight ratio takes over.

It is entirely possible I am wrong about that 1200m hill climbing 800 feet favoring someone like Contador. I'm basing it more on my own experiences against far less than pro quality riders, that is riders like myself. Although it always seems to me like in the pro peleton when someone goes on a hill like that, the sprinters usually get dropped.

Anyway, my own experience (at 5'8" mostly riding at 73-74KG) is that many guys who can destroy me in a sprint and sometimes even guys who beat me in my strength, 20K TTs, can't stay with me all the way up even a short hill like that if I am going hard. And I don't really consider myself a light climber or even a very good climber. It just seems like most people who can generate a lot of power can only keep it up for 30 seconds before massive power dropoffs. Perhaps by the time the pro peleton has selected itself, only sprinter types who can generate massive power without the radical dropoffs are left.

 

[BroDeal]

Anyone can go to http://www.analyticcycling.com and use their online calculators to find out how much difference a change in weight makes.

The real question is what effects does extreme weight loss have the amount of power a rider can produce. I am tempted to think that for sustainable power over longish time periods everything comes down to how much oxygen you can process, but that brings up the question of why a rider like Cancellara does not "pull a Wiggins" and lose 7kg to contend for the GC of a GT.

 

[Oldman]

Anyone can go to http://www.analyticcycling.com and use their online calculators to find out how much difference a change in weight makes.

The real question is what effects does extreme weight loss have the amount of power a rider can produce. I am tempted to think that for sustainable power over longish time periods everything comes down to how much oxygen you can process, but that brings up the question of why a rider like Cancellara does not "pull a Wiggins" and lose 7kg to contend for the GC of a GT.

Because he, like most good sprinters, know they'll only compromise the thing they do best and be average at best at climbing. Lots of good bits in this thread like the ability to sustain a climb based on fast/slow twitch muscles, etc. Good climbers don't necessarily climb each hill better than everyone else-they seize advantage on the type of hill that suits them or the portion of terrain. Again, climbing ability is judged by where you are at the finish.

 

[chase196126]

Anyone can go to http://www.analyticcycling.com and use their online calculators to find out how much difference a change in weight makes.QUOTE]

All you have to do is think about it in watts/kilo. If you figure that top gc riders are climbing at a rate of 6 watts/kilo (im just using a round number here) every extra kilo you have on your body requires 6 extra watts to go the same speed. So if it is true Wiggens lost 7-8 kilos, that is 42-48 watts or more that he is saving to go the same speed.


As far as actual time differences I cant say how a kilo would affect a rider in a set uphill course.

 

[BroDeal]

Anyone can go to http://www.analyticcycling.com and use their online calculators to find out how much difference a change in weight makes.QUOTE]

All you have to do is think about it in watts/kilo. If you figure that top gc riders are climbing at a rate of 6 watts/kilo (im just using a round number here) every extra kilo you have on your body requires 6 extra watts to go the same speed. So if it is true Wiggens lost 7-8 kilos, that is 42-48 watts or more that he is saving to go the same speed.


As far as actual time differences I cant say how a kilo would affect a rider in a set uphill course.

But most people want an answer to a question like if I weigh 75kg and generate 300W, how much faster up an 8% climb will I be if I drop 7kg. Air resistance needs to be taken into account. Analytic cylcing uses a decent model that factors in a lot of things in. You could, for example, not only reduce the rider's weight but also slightly reduce the frontal area to account for slightly less rider size due to the weight loss.

 

[poupou]

But most people want an answer to a question like if I weigh 75kg and generate 300W, how much faster up an 8% climb will I be if I drop 7kg. Air resistance needs to be taken into account. Analytic cylcing uses a decent model that factors in a lot of things in. You could, for example, not only reduce the rider's weight but also slightly reduce the frontal area to account for slightly less rider size due to the weight loss.

A small decrease of frontal area at 25km/h doesn't matter too much.

 

[rhubroma]

The thing is, at the level of the pros everybody goes uphill fast. Even the sprinters.

Then you have a lot of strong climbers at more or less the same weight. So naturally it is a power thing after that. There are just some guys that can simply fookin jam uphill! Fooking hell, they blow you and everybody away, even other strong guys. No matter how well prepared.

And then you realize maybe a beer would be better instead. Or maybe 2....

Talent mates, it all boils down to whether or not you've got the stuff, what it takes.

 

[cyclingmad]

Figures

This is what I am really interested in. I have posed the question before, to Coggan and others, but have not received an answer. We are talking significant amounts of weight loss in already skinny guys. They don't have the fat reserves to lose weight exclusively through fat loss, so they have to lose lean muscle mass to achieve this weight loss. If they are losing lean muscle mass, then wouldn't they also lose sustainable power? If so, is the power loss proportional to weight loss or is this extreme weight loss still beneficial because the power-to-weight ratio would still be higher at the lower body weight because of less loss of power compared to body weight?

At the very least, it would be an interesting study to assess the balance between weight loss (fat v lean muscle) and effects on sustainable power and power-to-weight ratio.

This is just pure Math (No physiology involved):

- No muscular loss
- No wind changes
- Just weight loss (8 kg)
- Same power output (443 watts on Verbier, 8.7 km)
- Time Gain: 1':48"

I hope I am not doing anything wrong. Just using same variables I was using. Whether I used the wrong variables or not what is important is the change not the absolute values.

I used calculations with power outputs to what Herrera and Lemond were doing in Alpe D’Huez which is a longer climb to values around 390 Watts And I get a time difference of 5 minutes.

Sometimes I wonder.

Gosh, I've never paid attention to this weight loss in detail, but if the numbers are correct his performance in the Tour was because he had the power already in him not because of his weight loss. But I guess this was already explained by JV that he was putting this kind of power in training.

Wiggins in Beijing was 82Kg so would have been close to this at last years tour de france. It was posted in the Vaughters wants to sign Contador thread but believe the weight loss to be 8Kg.

Verbier is approx 7% and the pace was approx 15 mph(24kph) at this pace and gradient the power output to overcome gravity is 2 Watts per lb. 8kg *2.2 approximates 18lbs so 36 Watts less power to sustain the same speed.

It isn't that precise as the gradient and speed vary along the way up so this is an average no-one rides perfect pace etc.

 

[Escarabajo]

...

Verbier is approx 7% and the pace was approx 15 mph(24kph) at this pace and gradient the power output to overcome gravity is 2 Watts per lb. 8kg *2.2 approximates 18lbs so 36 Watts less power to sustain the same speed.

It isn't that precise as the gradient and speed vary along the way up so this is an average no-one rides perfect pace etc.

That time translates into 42 Watts in my calculations. I don't use the internet programs anymore. I use my own program where I can adjust for different positions, head wind and drafting during different segments in the climb. Changes in speed make the calculations bigger, but when I have matched my calculations to some power tabs I have found it to be not that significant. Unless it is a pure climber who gets up and changes speed all the time (Contador and Schleck). But I have the feeling that we will never see their power outputs.

 

[TRDean]

Interesting comment by Alex Dowsett

Following the U23 time trial he was interviewed...he finished 7th by the way. Anyway, he states: How has 2009 been for you?
Alex: Not the best, I’ve had problems – I lost too much weight and with it, a lot of power. In Italy it’s important that you keep your weight down, but I over did it and it lost me two or three moths out of my season. I’ve really only done two good rides; 11th in the European time trial championships – and now, today.

So, Mr. Dowsett looses some weight...he does not say how much, but it greatly affected his power. I am sure it would be different between individuals, but I'm wanting to think that his situation is the common one. There is no way to loose 7Kg from an already fit person, and maintain power levels. Some of the weight has to be muscle mass.

 

[BikeCentric]

Following the U23 time trial he was interviewed...he finished 7th by the way. Anyway, he states: How has 2009 been for you?
Alex: Not the best, I’ve had problems – I lost too much weight and with it, a lot of power. In Italy it’s important that you keep your weight down, but I over did it and it lost me two or three moths out of my season. I’ve really only done two good rides; 11th in the European time trial championships – and now, today.

So, Mr. Dowsett looses some weight...he does not say how much, but it greatly affected his power. I am sure it would be different between individuals, but I'm wanting to think that his situation is the common one. There is no way to loose 7Kg from an already fit person, and maintain power levels. Some of the weight has to be muscle mass.

Good post. If any of you read the Wattage group on Google (bunch of dudes that discuss training with power) almost all of them state from personal experience that weight loss usually comes with a power output loss. Sometimes the weight loss can still up the power/weight ratio (slightly) and increase climbing ability slightly at the expense of flat ground TT power and sprint power.

And all of this assumes that one has a low body fat %. If you are an amateur that doesn't train a ton you should have several pounds of fat that can be safely lost and will do nothing but improve your all-around ability. I think 8% body fat is a pretty good target for most amateurs - that's the magic number for me anyway, below that % is very hard to sustain (i.e. caloric deficit while training), and above that % I will shed fat just by riding more without having to pay attention to diet. YMMV.

 

[Race Radio]

Wiggens certainly lost a significant amount of power. He would not be close to his pursuit times of a year ago.

 

[_frost]

Wiggens certainly lost a significant amount of power. He would not be close to his pursuit times of a year ago.

Why? Certainly less strength and less peak power but do you have some prove or can you explain the physiological mechanism why someone would lose a significant amount of (mostly aerobically produced that is needed for pursuit) power due to loss of muscle mass?