Harder into a headwind?



"Simon Brooke" <[email protected]> wrote in message
news:[email protected]...
> in message <[email protected]>,
> [email protected] (' [email protected]') wrote:
>
>> On Jun 20, 12:26 am, [email protected] wrote:
>>> On Jun 20, 9:02 am, Jenko <[email protected]> wrote:
>>>
>>> > [email protected] wrote:
>>>
>>> > > As a general rule, the time-minimizing strategy given a constraint
>>> > > on the total number of joules is to adjust your pace so you go a bit
>>> > > harder [...] into a headwind, and go a bit easier [...]
>>> > > with a tailwind.
>>>
>>> > Is that true? I thought the power-speed curve was more linear with a
>>> > tailwind, so that an extra effort there leads to a bigger speed
>>> > increase than when into a headwind.
>>>
>>> That's true, but in this case the issue is that there's another
>>> constraint: the course distance is fixed, too. That means that on an
>>> out-and-back you spend less time on the tailwind leg than on the
>>> upwind leg.

>>
>> Tell me Robert, could you do a 40 kph 10K?

>
> With 60Km/h of wind behind me I could. Or if the start was one thousand
> metres higher than the end. If it's an out-and-back, then no - at least,
> not without some very peculiar weather.


Well, my point is sort of that Joe is a great deal more likely to have
better judgement in this matter than Robert, you or I.
 
On Jun 21, 2:59 am, "Tom Kunich" <cyclintom@yahoo. com> wrote:

> Well, my point is sort of that Joe is a great deal more likely to have
> better judgement in this matter than Robert, you or I.


If TT performance reflected good judgement, Joseph should be following
Anquetil's suggestions.
 
On Jun 21, 1:24 am, Henrik Münster <[email protected]> wrote:
> In article
> <[email protected]>"joseph.santanie
>
> [email protected]" <[email protected]> wrote:
> > This newsgroup has a rather playful way of saying things. Nobody is
> > poking fingers at you. It's just that Anquetil (and many others) are
> > famous for many outrageously silly ideas (like the water bottle in
> > the pocket). And the contrast of how well he and others could ride
> > withthe sillieness of some of their ideas is funny.

>
> I find it funny and in a way quite charming too. I like the idea of
> putting the water bottle in your pocket to lighten the bike. Life
> shouldn't be too scientific or logical. At least not while we are
> riding our bicycles in our spare time. Perhaps I have forgotten about
> the way things are said in this group. I've been away for almost ten
> years due to lack of time. These rec.bicycle groups are quite busy and
> takes a lot of time to follow. In Denmark we have a small news group
> with only a few postings each day. I've only come back, since I'm
> trying a new news reader.


I find it quite charming too. Welcome back! Stick around, there is
some good stuff here sometimes.

Joseph

> > The main problem with the idea in the anecdote is that 25% more
> > effort does not always mean 25% more speed. And as Bill and Robert
> > have pointed out it is the relative differences between the speeds
> > acheived by different effort levels and the length of time spent at
> > this relative difference that matters, not just that 25% of 30 is
> > more than25% of 10.

>
> Of course you are right. I wasn't thinking straight.
>
> --
> Med venlig hilsen
> Henrik Münster
> Esbjerg
 
In article <[email protected]>, William Asher <[email protected]>
wrote:

> Henrik Münster wrote:
>
> <snip>
> >
> > Funny! Jacques Anquetil used to say, it is the other way around. If
> > you put in 25% more effort uphill, you go from 10 to 12.5 mph. If you
> > put in 25% more effort downhill, you go from 30 to 37.5 mph. So you
> > gain more from putting in some extra effort downhill and relaxing a
> > little uphill. Put that way, it sounds logic, but I can also see your
> > point about wind resistance. Anyway, Jacques Anquetil won 5 TdF and a
> > lot of time trials, so his theory worked for him.
> >
> >

>
> The French have always sucked at story problems.
>
> "A train leaves the station and then travels 10 miles at 12.5 mph and then
> 10 miles at 30 mph. A second train traveling on a different track leaves
> the same station and travels 10 miles at 10 mph and then 10 miles at 37
> mph. Which train arrives first?"


So what if the first train can only manage to do the first ten miles at 10.1 mph
(in spite of being almost in the red the whole time) and all other factors are the
same? In that case, it makes sense to try to make up some time by going downhill
faster, no? In other words, if one can't get up a hill 25% faster (via training or
orange juice), then it does seem like there's something to be said about making time
up in other parts of the course.

--
tanx,
Howard

Never take a tenant with a monkey.

remove YOUR SHOES to reply, ok?
 
Howard Kveck <[email protected]> wrote in
news:[email protected]:

> So what if the first train can only manage to do the first ten
> miles at 10.1 mph
> (in spite of being almost in the red the whole time) and all other
> factors are the same? In that case, it makes sense to try to make up
> some time by going downhill faster, no? In other words, if one can't
> get up a hill 25% faster (via training or orange juice), then it does
> seem like there's something to be said about making time up in other
> parts of the course.
>


The point is that nobody juices for descending because the big gains are
to be made in going uphill faster. Therefore, if you are focusing on
riding fast overall, you want to climb faster, going down is not going to
help you that much. You can easily lose 15 minutes on a big climb.
Reasonably, how much time can someone hope to recover on a descent that's
only 20 minutes long for the slowest descenders? As an example, Davis
Phinney tells the stirring story of how he barely made the time cut on
the Alpe d'Huez stage one year by descending really fast, but the overall
point is that he was way way behind the climbers so he was saving a few
minutes out of 30 or so (I forget how far back he was but it was a lot,
even with making up time in the descent). Maybe a better way to think
about it is would you rather be able to climb like Pantani or descend
like Savoldelli?

--
Bill Asher
 
On Jun 21, 9:11 am, William Asher <[email protected]> wrote:
> Howard Kveck <[email protected]> wrote innews:[email protected]:
>
> > So what if the first train can only manage to do the first ten
> > miles at 10.1 mph
> > (in spite of being almost in the red the whole time) and all other
> > factors are the same? In that case, it makes sense to try to make up
> > some time by going downhill faster, no? In other words, if one can't
> > get up a hill 25% faster (via training or orange juice), then it does
> > seem like there's something to be said about making time up in other
> > parts of the course.

>
> The point is that nobody juices for descending because the big gains are
> to be made in going uphill faster. Therefore, if you are focusing on
> riding fast overall, you want to climb faster, going down is not going to
> help you that much. You can easily lose 15 minutes on a big climb.
> Reasonably, how much time can someone hope to recover on a descent that's
> only 20 minutes long for the slowest descenders? As an example, Davis
> Phinney tells the stirring story of how he barely made the time cut on
> the Alpe d'Huez stage one year by descending really fast, but the overall
> point is that he was way way behind the climbers so he was saving a few
> minutes out of 30 or so (I forget how far back he was but it was a lot,
> even with making up time in the descent). Maybe a better way to think
> about it is would you rather be able to climb like Pantani or descend
> like Savoldelli?
>
> --
> Bill Asher


Exactly. Let's take me as a hypothetical example riding a time trial
up and down Alpe d'Huez using an online calculator.

14km up at 8% followed by 14km down at 8%. Let's even forget about
braking and turns and pretend it's a drag strip I can just pedal down
the whole way.

100kg 350W up 8% equals about 13km/h or 1 hour 5 min up. If I keep the
same effort on the descent I go a preposterous 78km/h and get down in
10 minutes 47 seconds. So my total time is 1:15:47.

If I add 20W on the way up and drop 20W on the way down the up time is
1:01:45 and the down time is 10:50. A little more effort on the way up
gained me 3 minutes and a little less on the way down lost me only 3
seconds. Total 1:12:35

If I drop 20W on the way up and add 20W on the way down the climb
takes 1:08:51 and the descent takes 10:44 for a total of 1:19:35.

Clearly adding extra effort on the way up is fastest.

Joseph
 
In article <[email protected]>, William Asher <[email protected]>
wrote:

> Howard Kveck <[email protected]> wrote in
> news:[email protected]:
>
> > So what if the first train can only manage to do the first ten
> > miles at 10.1 mph
> > (in spite of being almost in the red the whole time) and all other
> > factors are the same? In that case, it makes sense to try to make up
> > some time by going downhill faster, no? In other words, if one can't
> > get up a hill 25% faster (via training or orange juice), then it does
> > seem like there's something to be said about making time up in other
> > parts of the course.
> >

>
> The point is that nobody juices for descending because the big gains are
> to be made in going uphill faster. Therefore, if you are focusing on
> riding fast overall, you want to climb faster, going down is not going to
> help you that much. You can easily lose 15 minutes on a big climb.
> Reasonably, how much time can someone hope to recover on a descent that's
> only 20 minutes long for the slowest descenders? As an example, Davis
> Phinney tells the stirring story of how he barely made the time cut on
> the Alpe d'Huez stage one year by descending really fast, but the overall
> point is that he was way way behind the climbers so he was saving a few
> minutes out of 30 or so (I forget how far back he was but it was a lot,
> even with making up time in the descent). Maybe a better way to think
> about it is would you rather be able to climb like Pantani or descend
> like Savoldelli?


Oh, I completely agree that you gain much more going faster up the hill, but I
think you can also gain by working hard going downhill too. Besides, it rarely feels
like work when you put effort into going downhill (at least that's how it feels to
me).

--
tanx,
Howard

Never take a tenant with a monkey.

remove YOUR SHOES to reply, ok?
 
Howard Kveck wrote:

<snip>
> Oh, I completely agree that you gain much more going faster up the
> hill, but I think you can also gain by working hard going downhill
> too. Besides, it rarely feels like work when you put effort into going
> downhill (at least that's how it feels to me).
>


I sure seem to be going downhill effortlessly.

--
Bill Asher
 
In article <[email protected]>, William Asher <[email protected]>
wrote:

> Howard Kveck wrote:
>
> <snip>
> > Oh, I completely agree that you gain much more going faster up the
> > hill, but I think you can also gain by working hard going downhill
> > too. Besides, it rarely feels like work when you put effort into going
> > downhill (at least that's how it feels to me).
> >

>
> I sure seem to be going downhill effortlessly.


It's what we do best.

--
tanx,
Howard

Never take a tenant with a monkey.

remove YOUR SHOES to reply, ok?
 
On Jun 21, 9:11 am, William Asher <[email protected]> wrote:
> Howard Kveck <[email protected]> wrote innews:[email protected]:
>
> > So what if the first train can only manage to do the first ten
> > miles at 10.1 mph
> > (in spite of being almost in the red the whole time) and all other
> > factors are the same? In that case, it makes sense to try to make up
> > some time by going downhill faster, no? In other words, if one can't
> > get up a hill 25% faster (via training or orange juice), then it does
> > seem like there's something to be said about making time up in other
> > parts of the course.

>
> The point is that nobody juices for descending because the big gains are
> to be made in going uphill faster. Therefore, if you are focusing on
> riding fast overall, you want to climb faster, going down is not going to
> help you that much. You can easily lose 15 minutes on a big climb.
> Reasonably, how much time can someone hope to recover on a descent that's
> only 20 minutes long for the slowest descenders? As an example, Davis
> Phinney tells the stirring story of how he barely made the time cut on
> the Alpe d'Huez stage one year by descending really fast, but the overall
> point is that he was way way behind the climbers so he was saving a few
> minutes out of 30 or so (I forget how far back he was but it was a lot,
> even with making up time in the descent). Maybe a better way to think
> about it is would you rather be able to climb like Pantani or descend
> like Savoldelli?
>
> --
> Bill Asher


Exactly. Let's take me as a hypothetical example riding a time trial
up and down Alpe d'Huez using an online calculator.

14km up at 8% followed by 14km down at 8%. Let's even forget about
braking and turns and pretend it's a drag strip I can just pedal down
the whole way.

100kg 350W up 8% equals about 13km/h or 1 hour 5 min up. If I keep the
same effort on the descent I go a preposterous 78km/h and get down in
10 minutes 47 seconds. So my total time is 1:15:47.

If I add 20W on the way up and drop 20W on the way down the up time is
1:01:45 and the down time is 10:50. A little more effort on the way up
gained me 3 minutes and a little less on the way down lost me only 3
seconds. Total 1:12:35

If I drop 20W on the way up and add 20W on the way down the climb
takes 1:08:51 and the descent takes 10:44 for a total of 1:19:35.

Clearly adding extra effort on the way up is fastest.

Joseph
 
On Jun 21, 11:37 pm, "[email protected]"
<[email protected]> wrote:
> Exactly. Let's take me as a hypothetical example riding a time trial
> up and down Alpe d'Huez using an online calculator.
>
> 14km up at 8% followed by 14km down at 8%. Let's even forget about
> braking and turns and pretend it's a drag strip I can just pedal down
> the whole way.
>
> 100kg 350W up 8% equals about 13km/h or 1 hour 5 min up. If I keep the
> same effort on the descent I go a preposterous 78km/h and get down in
> 10 minutes 47 seconds. So my total time is 1:15:47.
>
> If I add 20W on the way up and drop 20W on the way down the up time is
> 1:01:45 and the down time is 10:50. A little more effort on the way up
> gained me 3 minutes and a little less on the way down lost me only 3
> seconds. Total 1:12:35
>
> If I drop 20W on the way up and add 20W on the way down the climb
> takes 1:08:51 and the descent takes 10:44 for a total of 1:19:35.
>
> Clearly adding extra effort on the way up is fastest.


However, this is not quite a fair comparison. Because the
climb is longer in time than the descent, if you add 20 W
on the way up and take off 20 W on the way down, you're
increasing the total energy (number of joules) expended.

It's not clear that one has a fixed number of joules to
burn in a TT, that is, maybe this isn't the best metric
for effort. Still, one could say "I know I can ride
at 300 W for an hour, or 320 W for 20 minutes and 280 W
for 40 minutes. What's the best pacing strategy for
a ~ 1 hour TT?"

If the TT is dead flat, constant power is better, but
if there are hills, increasing power on the hills is
better, strictly because speed is a shallow function of
power on the flat and a nearly linear function of power
on hills.

Headwinds are less clear cut. The issue is that you're
going slow into the headwind, so any increment in speed
helps cut down the time you spend going slow. However,
because the wind resistance term is so strong, you pay
dearly in power for any increase in speed. On the
tailwind section, wind resistance is less than normal
for a given speed, the rolling resistance term plays a
larger role, and the dependence of speed on power is
somewhat closer to linear than it would be without
the tailwind. For this reason, I think it's not as
efficient to hammer into the headwind section of an
out-and-back as it is to hammer up a hill.

Ben
 
On Jun 22, 12:47 am, "[email protected]" <[email protected]>
wrote:

> It's not clear that one has a fixed number of joules to
> burn in a TT, that is, maybe this isn't the best metric
> for effort.



If a rider doesn't achieve bonk, then there isn't (wasn't) a "fixed
number of joules" other than the maximum number over a time as
determined by a particular engine's capability.

There isn't ever a joule reservoir problem for low level amatuer
TT'ing. They are too short. Perhaps a little sugar intake might
help to top off blood sugar, but I'm skeptical that does much in an
amatuer (short) TT.
 

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