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Physics and hill climbing
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It is that time of year to start obsessing about getting ready for the hills of Lake Placid. Since I stink on hills, I am giving them serious thought. I have been setting up spread sheets of gear ratios and all that stuff. I started to wonder just why it was I stink so badly on hills. My mind wandered back to freshman physics (no asking how long ago that was). I pulled out my text book (yes, still have it), and I did a little homework. I found the results very interesting.

It turns out that one watt is equal to 44.25 foot pounds/minute. If I hop on my computrainer I quickly learn that it hurts to put out 200 watts for a long period of time. It also hurts to climb hills. No fair laughing at these numbers.

If I assume that my bike with me and my expanding middle weigh about 180 pounds fully equipped, that on a hill essentially all the energy goes into hauling my excessive mass against gravity, and that a bunch of the hills on that course are an approximate 7% grade (not sure of that but I will try to measure next time I am in town) and that I put out 200 watts during the climbs, I should expect to climb the hills at 8 mph. As it turns out that is just about exactly my speed up those hills. No comparing me to my Kona qualified friend who goes up the hills at 12 mph.

If this "model" is correct, it seems that no amount of strength or other kind of training will help unless it trains my body to put out more than my current 200 watts. Only that kind of training together with losing weight from my middle and my bike will help. Of course I need to have an efficient position and technique so that I am actually able to keep putting out those watts without fading excessively. In my case that means I have to spin.

Does any of this make any sense?

From the flatlands,
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Re: Physics and hill climbing [ajfranke] [ In reply to ]
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Yes. It is mostly all about the engine (and how much the engine weighs).

Frank

--------------
Frank,
An original Ironman and the Inventor of PowerCranks
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Re: Physics and hill climbing [ajfranke] [ In reply to ]
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It seems that you can also go faster up hills by being aero, provided your watts don't drop. Weight is relatively insignificant on a flat but matters on the hills. Here's Jim Martin's take on this. Stay aero and get light and you'll be faster. http://home.hia.no/~stephens/aero.htm
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Re: Physics and hill climbing [cerveloguy] [ In reply to ]
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If you have the time you might try to improve strength by doing leg presses and hill repeats. This will enable you to put out a few more watts going up and on the flats. Good luck.
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Re: Physics and hill climbing [cerveloguy] [ In reply to ]
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I don't think being aero helps much once you drop to an apparent wind speed of about 15 mph or less...then, I think comfortable breathing and Power are more important...both accomplished by a more upright body position than an aero position.



Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)
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Re: Physics and hill climbing [ajfranke] [ In reply to ]
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Art,

Analytic cycling has models built and verified to consider road grade, drag, rolling resistance, and rider power (among many other factors). You might want to take advantage of these models rather than refine your own. It's easy to use and very helpful.

http://www.analyticcycling.com/

Tony Geller
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Re: Physics and hill climbing [ajfranke] [ In reply to ]
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Art,

You've heard form me before but from what I hear from you, you haven't been listening. At 160lbs, you can't be that wide around the middle. You need to lose some weight around the bike. Leave that heavy wheelset back home in the flatlands of Florida and take the lightest thing you can find. Stay seated!Spin,Spin,Spin! You can get some hill work in your local parking garage. Everything will help. The best thing is to ride some hills, go up anything you can find.

And next year, run Miami Marathon. I was there three weeks ago and it was absolutely great! I loved every minute of it and I'll deffinately be back again.

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''Sweeney - you can both crush your AG *and* cruise in dead last!! 😂 '' Murphy's Law
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Re: Physics and hill climbing [ajfranke] [ In reply to ]
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I was told a long time ago that when climbing hills you shifted your weight back in the saddle (butt back in the saddle or even hanging over the back of the saddle) if you stay seated while climbing.

Is this correct posture or have I been climbing wasting power? (This seems just the post to piggy-back off).

Not a lot of climbing in Holland, so I need help from you non flat landers.

Henk

Alex Jonker
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Re: Physics and hill climbing [Henk J] [ In reply to ]
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         That's just what I do. I have a steep angled bike so I slide back til I'm a little over the back of the seat and try to keep spinning, stay seated even when you start grinding. When I get my first steep bicycle, I couldn't get up anything seated. I stood for almost every hill, but it takes too much out of you. Finally I forced myself to stay in the seat and now I'm just as strong uphill as ever and I save myself for the rest of the race

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''Sweeney - you can both crush your AG *and* cruise in dead last!! 😂 '' Murphy's Law
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I do listen [ In reply to ]
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My math convinced me that I need to try to this lard butt down to 150 come race day. When in race shape I am usually around 155. I was around 145 when I was a kid though, so you have to wonder. I changed my diet in a completely counter intuitive way this week and I have dropped some weight and seem to be recovering better. If this works out, look for a fun post on that subject soon. The biggest improvement would come from getting my age back down to 22, but all dead ends in that direction so far.

Once I get rid of my old fork, my bike should come in under 18 pounds for Lake Placid this year. Even with my disc, my wheel set is probably around 1500 grams total. It would be tough to get rid of more than a couple hundred grams there.

I usually spend two weeks in Lake Placid each year doing the bike course at least once a day. Other than that, I have to make do in Florida. Overpasses and parking garages are about it here. Nothing either natural or man made over 1000 feet in the entire state.

I did the Disney marathon this year, or at least I tried to. I reinjured my leg around mile 12 and hobbled to the finish of the half. I will fire it up again next year. I may reconsider and go for Miami next year. It was a pretty successful race from what I heard.

Old, fat and slow in Florida,
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