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Headwind vs. Hills(17 posts)

Headwind vs. HillsLen J
May 8, 2001 5:50 AM
New Poster(20 year rider), but have been following discussions for several weeks. Been impressed with the knowledge.
I live on the Eastern shore of Maryland. We have no hills but plenty of wind. Last night, on my normal after work ride, my last 10 miles were into a 20 mile/hr headwind. (Yes, it sucked) Does anyone know if there is someway to determine how cycling into a headwind compares to a hill? (What does a 10 mile/hour headwind equal in hill grade?)
re: Headwind vs. HillsJBergland
May 8, 2001 6:58 AM
Len J,
I would be very surprised if there is such a formula... there is just tooo many variables to account for. Headwinds are not always constant (gusts) and can change directions (some rides seem to be ALWAYS heading into the wind!!). I have heard of people using BOTH as training aids. A headwind with a big gear can feel like a very tough climb!!
re: Headwind vs. HillsET
May 8, 2001 7:01 AM
Obviously, it depends on your weight, power output, bike weight and tires, frontal surface area (whether you're riding aero or not), etc. The link below allows you to enter all this data and get the desired output. Warning: You will have to spend some time reading carefully about how to use it, make the proper conversions (e.g. lbs to kgs, miles to meters), know your power output, etc. Things such as typical power output and surface area are available; just ask here if you need help. Run it with your parameters for the 10 mph headwind at 0 grade, then run it again with 0 wind, altering the grade till it matches what you're looking for. You may say forget it, man, but if you want to do it right, this is it.

http://www.analyticcycling.com/DiffEqWindCourse_Page.html
re: Headwind vs. HillsLen J
May 8, 2001 7:05 AM
Thanks. I see what you mean about taking time. I'll let you know what I come up with.
If headwind = hillrollo tommassi
May 8, 2001 7:34 AM
Chicago equals Alps!!

It's never that windy, unless you get blown over while standing at a stop. THATS windy.

One thing headwinds can help you with is mental toughness. A hill, I figure, will at some point be over. The wind, however, never seems to quit - so it is a battle to see who quits first, me or the wind!

but I still hate them anyway!
I've never...4bykn
May 8, 2001 8:05 AM
...looked outside and said "it's too hilly to ride today", but the wind is a different story!
I've never...Len J
May 8, 2001 9:05 AM
Unfortunatly, if you don't ride in the wind here, you don't ride.
re: Headwind vs. HillsDinosaur
May 8, 2001 9:06 AM
I live in the foothills of the Sierra Nevada and do nothing but climb hills. The upside of hills it that a hill has a downside. Climbing has it's ups and downs, peaks and valleys. Big hills, little hills, steep hills, gradual hills, and of course the never ending downhill that makes it all worth while.

I seldom encounter wind as my rides are sheltered. Riding into a headwind I gotta say sucks. First you have to get down low and aerodynamic and make yourselve small. Holding that position is hard enough. Perhaps if you can plan your rides as going out into the headwind and coming back home with the wind at your back.

I don't think you can compare the two.

I'll take hills over wind anyday. When it does become extremely windy, I don't ride. I have to worry about a tree coming down and crushing me.

Anyway all this talk about wind has me feeling winded so I'm going to sign off.

Sorry if I sounded like a big wind bag.
We can come very close...bruceg
May 8, 2001 9:08 AM
...to the answer if we know the total weight of bike and rider, your speed on the road and if we use average values for aerodynamic and road surface drag. Neglecting the other variables for this particular problem won't change the answer enough to worry about. If you and the bike weigh 176 lbs. total and you're riding at 15 mph into a 10 mph direct headwind, you would be producing the same power (about 250 watts) as if you were riding with no wind at 15 mph up a 3.5% slope or 7.4 mph up a 9% slope. If you'd like the equations or want to plug in different numbers you can e-mail.
bruceg@otelco.net
re: Headwind vs. HillsTeach
May 8, 2001 9:47 AM
Can't help with the analytic side, but I'd love to know the answer to your question. I ride in a lot of wind but have to drive a bit to ride in hills. Having said that, the real fun is riding into a headwind climbing a hill. Ah, the best of both worlds!
let's remember also...ET
May 8, 2001 10:14 AM
it's not as useful or practical as one might think. I mean, when is a headwind even more or less constant throughout a ride? It depends on the distance, too. Does he want to go all-out for a mile at max power output for this distance and then collapse? What everyone usually wants is just a ballpark difference between headwind and gradient, but you really have to define the problem first, and once you realize what that means, it often spoils the fun.
Not Equalgrz mnky
May 8, 2001 10:57 AM
The problem is that while you feel increased load in both situations one is more equal than the other. Sticking to a closed loop, constant widn direction and speed, etc., etc. - when you climb a hill you raise your potential energy (PE=mgh) and you get it back when you descend. So it's a storage/release type of cycle and since you end up where you started you don't have any net change in the "system" energy. Now, when you ride in a wind the loss is frictional (wind resistance) and it varries as a squared function of the velocity of the relative wind. Going twice as fast doesn't require twice as much energy, but rather four times. So if you went straight up wind and then turned around and came straight down wind at the smae velocity it would take more energy that the no wind situation. Now we rarely get this ideal case so imagine a loop, sometimes the wind will be in alingment with your path (either with or against), but most of the time you will have some kind of cross component. The rule of thumb (and this is a very rough thumb) is that when you work out the vectors you will have a headwind component 70% of the time. The exact number varies by the speeds of the wind and the rider. So ultimately you are required to supply a lot more energy on a windy day than on a hilly ride - all other things being equal. Probably the best way to deal with this is to realize that the only thing that you can control is the energy you put out and that a heart rate monitor gives you an indiction of how hard you are working. If you just try and focus on the speed-time-distance data for your regular route you will get discouraged on windy days.

Given the choice I'd rather deal with hills over wind any day, but if you're just out training then it doesn't matter too much - work is work (energy over time).
Interesting plan ...Bosephus
May 8, 2001 11:11 AM
I met a couple the other day that are going to Europe to ride for a couple months. When I asked where, they said they were going to start somewhere in Britain and ride down wind. Which ever way the wind is blowing on that particular day is the direction they will ride. When they get to water they said they'd get on the closest boat and do the same thing on the other side.

Sounds kind of fun ... downwind everyday not much for strength building, but hey, training isn't everything.
Interesting plan ...Greg Taylor
May 8, 2001 2:48 PM
I did roughly the same thing on a trip to Ireland -- I planned the route it so that the prevailing winds would be at my back. This was pretty necessary -- there were a couple of spots where I had a headwind going down a signficant grade, and I had to pedal to keep from stopping...
re: Headwind vs. HillsLC
May 8, 2001 11:41 AM
The big thing that I think everyone missed hills is the standing part. Your position is completly different on a steep hill. You don't stand into a strong headwind, but on a steep long hill you have to stand unless you have very low gears...which most road bikes so not have. Standing uses different muscles, works your arms, chest and stomach because you pull up on the bars and your stroke is mostly a downward push, which makes your quads scream. When I try standing into a wind it is just not the same feel, maybe since the handlebars are in a higher position on a hill which makes it feel better to stand. A headwind is more like riding on the flats in too big a gear.
heartrateDog
May 8, 2001 11:49 AM
If you have a heartrate monitor, that will likely give you the truest indication of how hard you are working, short of a watt measurement device on the bike.

While styles of pedaling into a stiff headwind and up a steep hill are very different, essentially work is work; your heart and lungs won't know the difference. I suppose if you adopted a hillclimbing posture and a large enough gear, you could get the same workout riding into the wind, except for the bike's inclination.

Doug
heartrateLen J
May 8, 2001 12:40 PM
This makes good sense to me. This is in effect what I do since I balance cadence, gearing and heartrate in all my interval work. The only difference for me with wind is gearing (i.e. maintain the same heartrate & cadence that I want for the workout I'm doing by adjusting gearing) In fact, this is what got me thinking about this question of Hills vs Wind in the first place, because I know (from memory) that it is exactly what I did with hills (when I lived in an area with hills.) Soory for the circular path, but you really made some connections for me. Thanks.