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Teams & Riders Froome Talk Only

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Rollthedice

Rollthedice

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Arnout said:
Help me again, with less kg there you'll need to develop less watts right? Making the performance more believable?

I always have a lot of trouble processing this sort of abstract information :eek:
Click to expand...
It's the other way. They keep their weight secret since less Kg means more Watts/kg. From not normal straight to the already established alien level in Froome's case.
 
M

Merckx index

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Where did those data come from? I thought Froome/Sky refused to publish power tap data. Also, why is his body surface area indicated, since if the data are from a power meter, that is irrelevant. Surface area would only be relevant if the power were calculated from time up the climb, in which case his weight would be irrelevant. But since the power is shown at multiple time points, I assume it is SRM data. But then why is it said to be estimated?

Where is the link for this?
 
thehog

thehog

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Merckx index said:
Where did those data come from? I thought Froome/Sky refused to publish power tap data. Also, why is his body surface area indicated, since if the data are from a power meter, that is irrelevant. Surface area would only be relevant if the power were calculated from time up the climb, in which case his weight would be irrelevant. But since the power is shown at multiple time points, I assume it is SRM data.

Where is the link for this?
Click to expand...

Stages data you mean. No longer SRM.
 
Netserk

Netserk

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Merckx index said:
Where did those data come from? I thought Froome/Sky refused to publish power tap data. Also, why is his body surface area indicated, since if the data are from a power meter, that is irrelevant. Surface area would only be relevant if the power were calculated from time up the climb, in which case his weight would be irrelevant. But since the power is shown at multiple time points, I assume it is SRM data. But then why is it said to be estimated?

Where is the link for this?
Click to expand...

1) The picture says it's estimated.

2) Weight is not irrelevant. 8kg dead weight is relatively more for a light rider than a heavier rider.

3) Link
 
M

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So they time him at multiple points and estimated his power from the time and the gradient at that point? Sounds very difficult to do and likely a fairly high degree of uncertainty.

And yes, if it was by time, his weight is largely irrelevant. The weight of the bike makes very little difference. About 1%.

Check it out with a power calculator. If you use 68 kg and 65 kg, with 7 kg for the bike, and a 7% gradient (I’m guessing, but doesn’t matter much), the power required for a certain constant speed is 443 watts at the heavier weight, which is 6.51 watts/kg, and 427 watts at the lower weight, which is 6.57 watts/kg. Varying the speed and gradient within the range that they would have to be doesn’t have a significant effect on the result.

So Froome's weight is essentially irrelevant to this result. Time up the climb is proportional to watts/kg, so most of the weight is already normalized. The small amount added by the bike doesn't make enough of a difference to matter.

Not to say that Froome didn't put up very high power values. YMMV, but Ross at SoS has implied that anything over 6.2-6.3 for 45 min. is suspicious. This is a shorter haul, but greater power.
 
Arnout

Arnout

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thehog said:
Tip it on its head. Other way around. Less believable. Even .5kg makes a difference.

Chris Hoy can pump out 1000w for a short period and probably weights almost twice as much as Froome. Less weight means you have to get the power from somewhere.

That's why Wiggins & Dawg who climb like they do carrying circa 65kgs but then ITT like Tony Martin with so little weight. Meaning higher watts p/kg.

So, yes, lower weight means more ***.
Click to expand...

Right. But less weight also means you have to carry less weight uphill, which is an advantage. With your example, guys like Betancur (who is about 55kg I believe) would have to be superhuman to even be able to climb. They are not, because their lower power output matches their lower weight.

So if Froome were to be lighter, he would have to carry less weight uphill. As W/kg is a ratio, I understand if one alters kg without changing the other side (W) you will get rediculous estimations, however it isn't realistic to change only one side usually when talking about a well-trained athlete. So in case he is lighter, we can assume his W output is lower too (this is a bit controversial as Sky of course say they can manage to bring down weight without compromising power output, but still). If both Ws and KGs change, he will have the same W/kg, or a more advantageous ratio when Sky indeed manages to bring down KG without bringing down W.

Of course, the whole debate is about whether it's possible to have a clean athlete produce more than about 6W/Kg for an amount of time where endurance is the most important factor (I'd say 20min+ ).

I'm still rambling on a bit as I'm still not entirely sold on the idea that less weight makes this performance more suspicious. Probably just me.
 
Netserk

Netserk

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Merckx index said:
So they time him at multiple points and estimated his power from the time and the gradient at that point? Sounds very difficult to do and likely a fairly high degree of uncertainty.

And yes, if it was by time, his weight is largely irrelevant. The weight of the bike makes very little difference. About 1%.
Click to expand...
Okay I used some massive weight difference as an example, but it does show quite clearly that weight isn't irrelevant.

50kg rider

75kg rider

It's not just the relatively different weight of the bike, it's also air resistance and rolling resistance.
 
DirtyWorks

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Arnout said:
Of course, the whole debate is about whether it's possible to have a clean athlete produce more than about 6W/Kg for an amount of time where endurance is the most important factor (I'd say 20min+ ).
Click to expand...

Just to be clear to the casual reader, this w/kg ratio goes back to Ferrari reducing winning the TdF to highest w/kg ratio. To be triply clear, the ratios over 6.something occur within the context of a three week race, on the most difficult climbs. I don't remember if ITT's were included.

So, huge w/kilo ratios are entirely reasonable outside of three-week stage races.
 
DirtyWorks

DirtyWorks

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Netserk said:
Okay I used some massive weight difference as an example, but it does show quite clearly that weight isn't irrelevant.

50kg rider

75kg rider

It's not just the relatively different weight of the bike, it's also air resistance and rolling resistance.
Click to expand...

Pushing air out of the way and defying gravity are the two primary forces a cyclist must defy.

Rolling resistance can be removed from consideration as all riders at the elite level are using just about the same equipment.
 
oldcrank

oldcrank

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thehog said:
Tip it on its head. Other way around. Less believable. Even .5kg makes a difference.

Chris Hoy can pump out 1000w for a short period and probably weights almost twice as much as Froome. Less weight means you have to get the power from somewhere.

That's why Wiggins & Dawg who climb like they do carrying circa 65kgs but then ITT like Tony Martin with so little weight. Meaning higher watts p/kg.

So, yes, lower weight means more ***.
Click to expand...
Double that figure and you will be getting close, my friend.
 
thehog

thehog

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Arnout said:
Right. But less weight also means you have to carry less weight uphill, which is an advantage. With your example, guys like Betancur (who is about 55kg I believe) would have to be superhuman to even be able to climb. They are not, because their lower power output matches their lower weight.

So if Froome were to be lighter, he would have to carry less weight uphill. As W/kg is a ratio, I understand if one alters kg without changing the other side (W) you will get rediculous estimations, however it isn't realistic to change only one side usually when talking about a well-trained athlete. So in case he is lighter, we can assume his W output is lower too (this is a bit controversial as Sky of course say they can manage to bring down weight without compromising power output, but still). If both Ws and KGs change, he will have the same W/kg, or a more advantageous ratio when Sky indeed manages to bring down KG without bringing down W.

Of course, the whole debate is about whether it's possible to have a clean athlete produce more than about 6W/Kg for an amount of time where endurance is the most important factor (I'd say 20min+ ).

I'm still rambling on a bit as I'm still not entirely sold on the idea that less weight makes this performance more suspicious. Probably just me.
Click to expand...

Yes and no. There is a transecting point and which one is too light to produce the required power. You are right that carrying less weight uphill is advantageous but you have to be careful that by being too light, ie less muscle mass that you're still able to produce the required (desired?) power. You need muscles to produce the power and to carry the oxygen. Muscle mass loss can be detrimental to power. Except Sky riders of course ;)

That's what makes Froome the anomaly in all of this. As to Wiggins. Massive weight loss with increased power on climbs and the ITT.

Just how one does that is anybody guess.

All of this of course is not an exact science. Perhaps better categorized as an imperfect science.
 
M

Mellow Velo

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thehog said:
Tip it on its head. Other way around. Less believable. Even .5kg makes a difference.

Chris Hoy can pump out 1000w for a short period and probably weights almost twice as much as Froome. Less weight means you have to get the power from somewhere.

That's why Wiggins & Dawg who climb like they do carrying circa 65kgs but then ITT like Tony Martin with so little weight. Meaning higher watts p/kg.

So, yes, lower weight means more ***.
Click to expand...




oldcrank said:
Double that figure and you will be getting close, my friend.
Click to expand...

This.
2300w I believe.

Cav, Greipel and co hit 1500+w in sprint mode.
Same figure for female track sprinters.
That's 1500w at 60-65 kgs.
Quite normal.;)
 
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