Reducing bike weight v's body weight

mtb101

mtb101

Likes Bikes and Dirt
carpetrunner said:
Design Of Experiment
- select (n=1), super masters class MTB rider, no chance of radical improvement influencing the result
- same bike (2009 Spec Enduro Comp)
- change rider weight
- ride the same event

Conclusion
A loss of 15% in rider mass in combination with moderate training can result in a 31% improvement in race times
- woohoo!!! :eek:range:
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good post and good outcome for you. less weight has to result in a faster rider, of course it's the power to weight ratio that crucial. and probably more weight can be shed from the body than the bike. then again no one wants to try and throw a 14kg bike slug through the bush. my training bike is 13.5kg, yes it's a slug to get it rolling, but when I get on my skinny stallion of a bike (11kg), feels like each pedal stroke will lift front wheel - much nicer ride experience. Of course when you hit the big climbs its strength, attitude, skills and hopefully all that training gets you over the top. your body weight ratio to power output has to be a significant factor, especially over more and more accumulated climbs.
 
fergo

fergo

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carpetrunner said:
Design Of Experiment
- select (n=1), super masters class MTB rider, no chance of radical improvement influencing the result
- same bike (2009 Spec Enduro Comp)
- change rider weight
- ride the same event

Mass
2010 Highland Fling, rider mass = 94kg --> 9h20m (560min)
2011 Highland Fling, rider mass = 80kg --> 6h25m (385min)


Training
2010 - 4 weeks - 13km commute each way = 520km (25hrs)
2010 - the subject had the flu 5 weeks out = 1800km (80hrs)

notes,
2010 tyres - eskar 2.35, saddle std (300g),
2011 tyres - 2.2 raceking(F), 2.0 raceking(R), tubeless, saddle phenom (220g)

Conclusion
A loss of 15% in rider mass in combination with moderate training can result in a 31% improvement in race times
- woohoo!!! :eek:range:
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Not sure the DOE is entirely isolating all contributing factors. The highland fling thread reports most people were faster than last year. Apparently there was a course change. (I didn't do it, just reading the thread) See quotes:

Mal Rob said:
I came over with two friends from Adelaide for this event and am amazed at how much faster category winners (and everyone else?!) rode this year compared to 2010...
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top_oz_bloke said:
I didn't even notice the mirror. Gee the times were fast today - I thought I was going ok but seems everyone else got faster as well!
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Rambler said:
... Full Fling times were much quicker than last year. A lot of people seemed to have bettered their best times by 30minutes. The time gain seemed to be in the Wingello loop. I am thinking some hill climbing was cut after the longest climb on the traditional yellow loop. ...
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FWIW, fat guys are slower than slim guys. Lose the weight, increase fitness times go faster. Shaving grams ie 0.1% off a total weight 100kg +, has zero effect compared to losing 10% body weight and increased power output and endurance.
 
macca21

macca21

Likes Dirt
Now, here's how I see it... not entirely related to bike vs body weight... but it all helps.

No fat does not equal fit. Losing weight on it's own will not make a massive difference, the big difference will come from the training you do whilst losing weight.
For instance, if I do no exercise for 4 weeks I can shed 4 - 6kg of body fat with minimal muscle loss... but I won't be any fitter and almost certainly won't ride much quicker if at all.
On the other hand, if I get out and ride while eating for performance, (plenty of carbs etc), and maintain my weight, I will most certainly be going quicker.

Also,
READ THIS! A dialed bike set-up, Ie. tyre pressure, suspension and comfort will far outweigh small weight losses here and there.
Don't go loosing so much body weight that it's going to result in a loss in power to weight. That will make you slower.

Basically, if you have the fat there to burn, then you may as well... BUT, if you don't really have that much to lose... just get fitter by putting in time on the bike.

All of the above being said, a light bike is definitely faster, and if you have the money then go for it... it sure won't slow you down!

Finally, despite all the studies being thrown around, I do think that 10kg on the body is a lot easier to move than a 20kg bike!
 
floody

floody

Wheel size expert
My anecdotal observations about being a fat bloke to varying degrees.

Over the past 15 years I've ridden bikes from 10.5-23kg, and as a rider I have ranged from 82kg to 115kg, up and down a couple of times.

When you're over about 95kg, it becomes considerably more difficult to ride technical terrain fast. Suspension is getting to its limits to what it can manage in terms of maintaining bike position in the travel etc, its a knife edge to bike setup and very unforgiving when you ride out of the envelope. It also works tyres a LOT harder.
Your weight gets hard to position on the bike; cornering, manualling, prejumping, pumping, scrubbing etc etc require a LOT more body English than at say 85kg. This makes a big difference to your effectiveness covering ground. Fat is pretty much unco, hard to be smooth, place the bike etc.

Climbing? Well, even the first 5kg makes a big difference when you're on the comeback path, this is pretty much indisputable, but its more the training than weight. Over the years I've been race-fit 95kg, and post injury 82kg at different times...Race-Fit 95kg me would tear out of condition 82kg me a new one. Fit 95kg me was unstoppable out of the gate and aggressive in the turns, post injury 82kg me was feeble by comparison. At least partly psychological.

Bike weight? I've been fat on a heavy bike, fat on a light bike, fit on both. I can categorically say even as an unfit 105kg guy at the minute, I could CERTAINLY feel the benefit of a few hundred grams to a couple of kilos off the bike. It makes a big difference. The 'bike weight doesn't matter if your're fat' line is a load of bullshit. I would go as far as saying, in my experience, a couple of kilos of bike makes a bigger difference than a couple of kilos of body weight, relative fitness being the same.

Fitness makes a bigger difference than any other factor though.
 
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fatkiduptheback

fatkiduptheback

Squid
Floody makes some good points. From the perspective of someone who is lanky and just a little bit scrawny, weight does make a HUGE difference to climbing ability. You only need to look at all those anorexic Tour de France riders, they do sacrifice some power for weight.

However, one point from personal experience, there is a huge conception that lighter is always better. It is often forgotten that it is virtually impossible to become stronger and develop your cardiovascular system whilst losing weight or maintaining a weight that is lower than your body is comfortable with.

I wonder how weight effects the damage done in a crash. How much does having some protective fat and muscle prevent injury in a crash? Or whether because a lighter person has less momentum, they will come to a stop before more damage is inflicted.
 
fezi

fezi

Likes Dirt
fatkiduptheback said:
Floody makes some good points. From the perspective of someone who is lanky and just a little bit scrawny, weight does make a HUGE difference to climbing ability. You only need to look at all those anorexic Tour de France riders, they do sacrifice some power for weight.

However, one point from personal experience, there is a huge conception that lighter is always better. It is often forgotten that it is virtually impossible to become stronger and develop your cardiovascular system whilst losing weight or maintaining a weight that is lower than your body is comfortable with.

I wonder how weight effects the damage done in a crash. How much does having some protective fat and muscle prevent injury in a crash? Or whether because a lighter person has less momentum, they will come to a stop before more damage is inflicted.
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How do you figure Tour riders sacrifice power for weight? Also why can't your cardio improve whilst losing weight?
 
fatkiduptheback

fatkiduptheback

Squid
fezi said:
How do you figure Tour riders sacrifice power for weight? Also why can't your cardio improve whilst losing weight?
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Good points. I am no professional in either field, but I will try to explain what I think I know. Look at Andy and Frank Schleck. Without getting into a discussion as to why they lost to Cadel this year (I would have to start a new thread), they are of a very slight build. This slight build results in less power and less weight which allows them to climb faster but makes them slower on the flat.
 
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pharmaboy

pharmaboy

Eats Squid
fezi said:
How do you figure Tour riders sacrifice power for weight? Also why can't your cardio improve whilst losing weight?
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TDF winners usually have a bmi around 20 to 22. firstly, they select themselves as TDF riders prospectively - so riders with a tendency towards power and strength ride the velodrome events, and dont concern themselves with 300km hilly terrain road races. Also tall guys dont make good TDF prospects. They also train by riding, not by pressing weights in the gym.

You can of course improve cardio while losing weight, but the question is where you are versus your ideal weight - most of us are way above our ideal weight for cycling so the point is moot - if you are already at ideal weight and body fat v muscle mass, then losing weight is going to impact on your ability to train at vo2max - ideal i think for men is about 5% to 10% body fat - get below that and you reduce your vo2max. Ipso facto, once you have got to ideal weight/fat/muscle you want to try and stay there.
 
jathanas

jathanas

Likes Bikes and Dirt
pharmaboy;2471702...[B said:
most of us are way above our ideal weight for cycling so the point is moot[/B] - if you are already at ideal weight and body fat v muscle mass, then losing weight is going to impact on your ability to train at vo2max - ideal i think for men is about 5% to 10% body fat - get below that and you reduce your vo2max...
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Excellent post. Thx! J
 
fatkiduptheback

fatkiduptheback

Squid
pharmaboy said:
You can of course improve cardio while losing weight, but the question is where you are versus your ideal weight - most of us are way above our ideal weight for cycling so the point is moot - if you are already at ideal weight and body fat v muscle mass, then losing weight is going to impact on your ability to train at vo2max
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True that.
 
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fezi

fezi

Likes Dirt
pharmaboy said:
TDF winners usually have a bmi around 20 to 22. firstly, they select themselves as TDF riders prospectively - so riders with a tendency towards power and strength ride the velodrome events, and dont concern themselves with 300km hilly terrain road races. Also tall guys dont make good TDF prospects. They also train by riding, not by pressing weights in the gym.

You can of course improve cardio while losing weight, but the question is where you are versus your ideal weight - most of us are way above our ideal weight for cycling so the point is moot - if you are already at ideal weight and body fat v muscle mass, then losing weight is going to impact on your ability to train at vo2max - ideal i think for men is about 5% to 10% body fat - get below that and you reduce your vo2max. Ipso facto, once you have got to ideal weight/fat/muscle you want to try and stay there.
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Now I'm more confused! So losing body fat makes it harder to train your vo2 system in your body?

Also Bradley Wiggins was a world track champion but went pretty good at both the tour and vuelta. Same for Brad Mcgee too. Both of these and the Schleck's are pretty tall too. So much too learn. Keep the info coming guys
 
cha_cha_

cha_cha_

Likes Dirt
Less than 5% body fat is a very unhealthy state to be in. the body requires fats for many different functions and so a very low body fat percentage can lead to many different health problems. In this condition the body would be unable to make any sort of training gains.

Wiggins and mcgee were both pursuiters. They have immensly high avg power over, say 5 minutes. High Avg power over 5mins relates much more directly to high critical power and high power at threshold (which is what you need to be a pro roadie) than it does to short term power I.e. over times less than 1min as you would see in guys like perkins or hoy.
 
cha_cha_

cha_cha_

Likes Dirt
Also, kg per centimetre in height is probably a better measurement of physical suitability than bmi. Pretty sure most pros are somewhere near 0.35 to 0.45...

That still allows for some tall pros (johnny hoogerland is over 6' I think) and of course the sprinters are at the bulkier end of that ratio and beyond...
 
fezi

fezi

Likes Dirt
cha_cha_ said:
Also, kg per centimetre in height is probably a better measurement of physical suitability than bmi. Pretty sure most pros are somewhere near 0.35 to 0.45...

That still allows for some tall pros (johnny hoogerland is over 6' I think) and of course the sprinters are at the bulkier end of that ratio and beyond...
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I'm not sure height has much to do with it at all. Big Mig was 188cm tall and won 5 tours. Frandy is 190cm tall and has come 2nd in every tour since jesus was out of nappys. Must all come down to the right beef your eating I reckon. Yeah sure that evans bloke is 4'1" tall but we'll let him off for being a freak. Armstrong had a BMI of 22.1 and Wiggins is 190cm tall. All pretty handy cyclists I think and the current world champ Jaroslav Kulhavy is 187cm plus Steve Peat is a monster at 191cm.

So I need to be taller and get some fat in my diet to be fast apparently?
 
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