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TAW
03-31-2009, 11:27 AM
I think about this when I'm doing a TT, so I want your opinion.
You've just crested a hill and are somewhat fatigued. In front of
you is a moderate downhill (say 3-5%) which may last a while.
In order to conserve your energy and yet keep up speed, do you:

1. Crest the hill, pedal up to speed, then coast down hill
2. Pedal down the hill in a lower cadence, bigger gear
3. Spin down the hill in easier gear

Give me your expert advice! ;)

Thank you.

fourflys
03-31-2009, 11:31 AM
I've always heard it's better to soft pedal (spin) to work the lactic acid out of your muscles then to just coast. But, I'm sure someone with more experience will chime in here.

regularguy412
03-31-2009, 11:38 AM
IMHO -- gear up, pedal slower, but with still some pressure on the pedals so you can take advantage of the hill. How far you gear up depends on the steepness of the downhill grade -- you don't want to pedal at a 30 cadence. Let the speed come up gradually in the gear so your legs can recover.

All that goes out the window if you're racing. You have to try and get as much back from the hill on the down-side as you gave up during the climb. That means, pedaling it up through the gears, tucking up and coasting.


If you're talking about how to climb _during_ a TT, that's a different thing. Use your power meter or HRM to tell you what kind of energy you're putting out. You should actually try different methods, so that you learn what _your_ body wants.

Mike in AR:beer:

Richard
03-31-2009, 12:17 PM
As close as practical, match the effort going down as you did going up -- gear up and hammer!!

Karin Kirk
03-31-2009, 12:28 PM
I would opt to gear up and pedal down the hill. I don't mean to be a wise-ass, but in a TT the goal is not to conserve energy, it's to hammer yourself thoroughly. I try to extract every ounce of speed from downhills, so I go at them with the same vigor as the rest of the course.

If you are not racing and your primary concern is recovering, then spinning would be a fine approach, maybe with some coasting on the steeper sections.

zap
03-31-2009, 12:59 PM
If I'm going to do a hilly TT, I'll check out the route and then do a practice run at tt pace.

More time is lost on climbs so I always put out more effort in the climbs and then pedal downhill at a lower cadence and slightly reduced effort. I time it so that I've recovered some at the bottom and then continue on the flats close to what my effort was on the climb.

Throw in some wind and I do the same, more effort into the wind, slightly less with.

EDS
03-31-2009, 01:18 PM
If I'm going to do a hilly TT, I'll check out the route and then do a practice run at tt pace.

More time is lost on climbs so I always put out more effort in the climbs and then pedal downhill at a lower cadence and slightly reduced effort. I time it so that I've recovered some at the bottom and then continue on the flats close to what my effort was on the climb.

Throw in some wind and I do the same, more effort into the wind, slightly less with.

Agreed.

Ken Robb
03-31-2009, 01:42 PM
[QUOTE=Karin Kirk]I would opt to gear up and pedal down the hill. I don't mean to be a wise-ass, but in a TT the goal is not to conserve energy, it's to hammer yourself thoroughly. I try to extract every ounce of speed from downhills, so I go at them with the same vigor as the rest of the course.

Ken Robb wonders: I'm not now nor ever will be a racer so this is just idle musing but if a racer has just "X" amount of energy to use during a tt which plan would give the better result overall? He pedals as hard as he can down a steep hill and increases his speed there a little. The drag increases as the square of speed so if he can coast at 45 mph pedalling might get him to 47 mph.

He coasts or soft pedals at 45mph until the road flattens out and then feeling fresh he pedals hard; harder than if he had burned much more of his energy pushing hard down the hill. In theory the same extra energy spent now would increase his speed by a greater amount--maybe from 30 to 33 or 35 mph. The length of the race still to run would affect this strategic pondery of course. I know some riders NEVER run out of energy but how would this play out for near-normal people?

Spicoli
03-31-2009, 01:43 PM
25% over your head/harder on the way up and a "little" easier on the way down while working on making yourself as SMALL as possible. Time to gain going up while going just as hard on the down does not get as much bang for the buck. So ie; puke going up and try not to crash/get small when going down ;)

Just my take, take it or leave it :beer:

RPS
03-31-2009, 02:02 PM
If I'm going to do a hilly TT, I'll check out the route and then do a practice run at tt pace.

More time is lost on climbs so I always put out more effort in the climbs and then pedal downhill at a lower cadence and slightly reduced effort. I time it so that I've recovered some at the bottom and then continue on the flats close to what my effort was on the climb.

Throw in some wind and I do the same, more effort into the wind, slightly less with.+1
Math supports this approach.

TAW
03-31-2009, 03:08 PM
I would opt to gear up and pedal down the hill. I don't mean to be a wise-ass, but in a TT the goal is not to conserve energy, it's to hammer yourself thoroughly.

As some have replied, I'm trying to gauge my effort to decide which is more efficient over the long haul. Besides this, I occasionally do some duathlons where there is a run after the bike leg. I'm a better climber than I am on flats, so I'm wondering what's best for the legs to recover.

paczki
03-31-2009, 03:59 PM
[QUOTE=Karin Kirk]I would opt to gear up and pedal down the hill. I don't mean to be a wise-ass, but in a TT the goal is not to conserve energy, it's to hammer yourself thoroughly. I try to extract every ounce of speed from downhills, so I go at them with the same vigor as the rest of the course.

Ken Robb wonders: I'm not now nor ever will be a racer so this is just idle musing but if a racer has just "X" amount of energy to use during a tt which plan would give the better result overall? He pedals as hard as he can down a steep hill and increases his speed there a little. The drag increases as the square of speed so if he can coast at 45 mph pedalling might get him to 47 mph.

He coasts or soft pedals at 45mph until the road flattens out and then feeling fresh he pedals hard; harder than if he had burned much more of his energy pushing hard down the hill. In theory the same extra energy spent now would increase his speed by a greater amount--maybe from 30 to 33 or 35 mph. The length of the race still to run would affect this strategic pondery of course. I know some riders NEVER run out of energy but how would this play out for near-normal people?

As "Cannibal" Kirk points out it's also being in the right mind frame and staying in the "I want to crush the course" mode. There are diminishing returns in being overexuberant of course.

Ti Designs
03-31-2009, 06:05 PM
A few little details about time trialing:

First, it takes far more energy to go from 30 to 31 MPH than it does to go from 20 to 21. At some point it's a waste of energy to try to go faster down a hill. A number of years ago a number of riders came into the shop looking for cassettes with an 11 for the prologue of the Fitchburg stage race. It was a short down hill followed by a longish uphill. I told them they would be better off starting the uphill at a lower heart rate and what they would gain with the 11 was minimal. Nobody ever listens to me - I did notice the guys pushing the 11 posted some of the slowest times.

Second - and this is something often overlooked, speed over the top of the hill counts far more than speed at the bottom of the hill. It's all about speed over time (DvDt for those doing the math), if you go over the top with an extra 2 MPH you go down the other side that much faster from the top.

Third, I'm not a big fan of electronic devices for racing, but the power meter doesn't lie, and the your heart rate is a trailing indicator. By the time you feel like you're blowing up, or your heart rate makes it's way past your AT, it's too late. Train with power, race with power as a limiter on effort.

Karin Kirk
03-31-2009, 09:35 PM
As "Cannibal" Kirk points out it's also being in the right mind frame and staying in the "I want to crush the course" mode. There are diminishing returns in being overexuberant of course.

That's my approach anyway. I think about extracting speed from the course at every opportunity, whether it's up, down or flat. This is largely a mental approach that keeps me in "GO" mode for the whole race.

That said, of course you only have a finite amount of energy. However, for the most part you simply can't work at the same level of intensity on a significant downhill or with a stiff tailwind. Unless you've got some giant gearing or can spin huge RPMs in your TT tuck, you won't be generating the same kind of power on the way down. You will recover somewhat almost no matter what. Given that, I like to keep my focus of going as fast as possible on the downhills.

The advice of cresting the hill strongly and getting as small as you can for the descent are spot on too.

rounder
03-31-2009, 10:44 PM
Come on Ken. Just wondering. You are a racer. What do you do if there are 10 laps to go and you have enough gas, tires and car is working fine but is a little slower than the two cars in front of you. You know that if you do not pit for gas, you may run out, but not probably. If you do not stop for tires, you can make it, but you will probably lose some seconds each lap because they no longer handle right.

(a) you never won before...but now you have a chance.

(b) You have won lots this year, but you need to win today to win the championship and retain your sponsor

(c) you just want to win because that is what you do and what everyone expects

I know this is hypothetical and has not much to do with riding around on bikes. Just wondering. Thanks.

TAW
04-01-2009, 10:29 AM
Thank you, everyone, for your replies. Typically in a race I'll
go uphill fairly hard, then grab another gear (or two) at the top
and lower the cadence on the downhill sections, rather than
coast. But, of course, experience doesn't always dictate what
is best, so I appreciate your input. :)

Ken Robb
04-01-2009, 12:41 PM
Come on Ken. Just wondering. You are a racer. What do you do if there are 10 laps to go and you have enough gas, tires and car is working fine but is a little slower than the two cars in front of you. You know that if you do not pit for gas, you may run out, but not probably. If you do not stop for tires, you can make it, but you will probably lose some seconds each lap because they no longer handle right.

(a) you never won before...but now you have a chance.

(b) You have won lots this year, but you need to win today to win the championship and retain your sponsor

(c) you just want to win because that is what you do and what everyone expects

I know this is hypothetical and has not much to do with riding around on bikes. Just wondering. Thanks.

Beats me.
You aren't the first person to think that because I have taught high-performance driving to many people over 20+ years that I must be a racer but that's not true. Many of my former students have gone on into racing but I was never willing to invest the $$ and time required. I did do quite a bit of time-trialing and auto-crossing but no wheel-to-wheel racing. Now if you want to know what happens when you turn in too early and find yourself on what we call the "Oh Shoot" line (or words to that effect) call me. :)