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  1. #1
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    Cydesdale and the Greyhound

    I've ridden bikes all of my life, some years more active than others. This year has been one of the more active ones as I've been working on getting into better shape for longer rides I'd like to do. One recent innovation is to start the ride early: it's quiet, calm, little traffic, and there is more wildlife to see in the local mountains.

    My co-worker John, who commutes to work by bicycle every day (roughly 40-mile round trip) heard about these rides and expressed some interest. Normally each of us rides alone. He's near Chino Hills (Los Angeles) and I'm in Santa Monica. We decided to meet and see how it went.

    We met at my apartment and rode from there. He's about 135 pounds; at one time he'd been much heavier, but riding to work trimmed all of that. I'm about 220. Up the beach we went, then turned inland to Amalfi Drive and up. It's a steady climb to around 2000 feet.

    The ride went very well. Did a total of about 35 miles. John had a camera, so we'd stop to take pictures, or to look at the view, or to look at what few flowers are still in bloom up there.

    After we got back, I got to thinking about what we'd done. I still think it's neat that human beings can do this kind of thing. Where does the energy come from? Then I did some rough calculations. With my bike I'm about 250 pounds, and we climbed 2000 feet, so that's 500,000 foot-pounds of work done. John is about 160 with his bike, so he did 320,000 foot-pounds. Big difference.

    The climb was easy for him, it seemed; he rode at any pace I set. If I got a bit of extra energy and increased my speed, he'd easily match it, and hardly seemed to sweat at all. We rode a route I've been on several times, and we were riding faster than I usually do. I got hungry sooner than usual (when alone, I take about 4 hours to do the loop and don't need to eat anything, although I'm hungry when I get home) so we stopped for a snack on top.

    All of which got me to wondering about where the energy comes from. Clydesdales are big, but presumably store more energy somehow. I just get curious about such things. Riding a bicycle in mountains, up steep hills, still carries a whiff of magic to me.

  2. #2
    Senior Member RedC's Avatar
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    It seems like cheating to enjoy doing something that's good for you, doesn't it. Sunday my two friends and I left the start at the same time as the "A" group and were 33 miles into a 46 mile ride when one of the "A" guys called my buddy to see where we were. They had finished a 60 mile ride in the time it took us to do 33. One of the guys that started with them said they dropped him when the pace hit 28. I have to be going down a pretty significant hill (for these parts) to hit 28mph
    Red, like the color my hair used to be.

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  3. #3
    Banned. Mr. Beanz's Avatar
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    One of the reasons he might have easily matched your pace is that Chino Hills is nothing but HILLS! I have friends there so it used to be a trainging ground for us, when they rode. We would do repeats over Grand Ave. Sometimes Grand thru Carbon Canyon, back over Grand then to SanDimas around Raging Waters (Bonelli Park). 30-50 mile loops.

    If he does these rides regularly, then it could be that he does more hill work than you do, nothing more. The more climbing you do, the better you will get. I wouldn't be surprised if he had to struggle to keep up if you started training in the hills.

    MY buds were 150 lb'ers and I was 250. They said I could never keep up with them cause they had climbing bodies (my buds are arses!). I started training in the hills and that has changed!

    When I dropped down to 220 and beat them by over an hour in BigBear, they quit riding with me! Oh well, they sucked anyway!

    Your bud does sound cool to ride with you though. You got all the motivation and support right there. go with it!

  4. #4
    Senior Member LandKurt's Avatar
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    Quote Originally Posted by Lord Chaos View Post
    After we got back, I got to thinking about what we'd done. I still think it's neat that human beings can do this kind of thing. Where does the energy come from? Then I did some rough calculations. With my bike I'm about 250 pounds, and we climbed 2000 feet, so that's 500,000 foot-pounds of work done. John is about 160 with his bike, so he did 320,000 foot-pounds. Big difference.
    The energy comes from food, as you well know. Those half million foot pounds of energy convert to only 162 food calories. That's the energy in 0.74 oz. of stored fat. Of course, you burned more energy than that with wind resistance, friction and imperfect conversion of food to mechanical energy. I've heard 40 calories burned per mile, but that has to vary a good deal based on hills, speed, weight, headwind, and training.

    I often wonder about how many watts I'm putting out. I'd love to have a power meter just to see the figures, but I can't justify the expense out of idle curiosity. I've seen a Kurt Kinetic graph that indicates it takes about 100 watts to maintain a speed of 13 MPH on the level for an average (probably non clyde) rider. That goes up to 200 watts at 18 MPH, 500 watts at 27 MPH, and 1400 watts if you want to hit 40 MPH.

    I've tried computing what it takes to get me up a hill. I've got it figured at speed times grade times a constant of about 6. That is: going 10 MPH up a 5% grade is 10 x 5 x 6 = 300 watts. So I think I manage to put out 300 - 400 watts for short periods up hills. Good riders probably maintain that for the entire ride.

    What amazes me about humans is the different levels of capability. I'm beyond rank novice cyclist, but I've got a lot farther I could go.
    The upside of hills is the downside

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    I've read that human beings put out about 100 watts when resting, so the 100-watt figure for 13mph sounds about right. Anyone can ride a bike at 10mph.

    Horsepower is work over time, 550 foot-pounds per second. We did our 2000-foot climb in about two hours, I think. That was with time for photographs and such. So, 500K foot-pounds over two hours... equals not that much horsepower. It's a bit misleading because of the distance we covered also, which was about 13 miles.

    I just talked with John this morning. He wasn't tired on Saturday, as I was, but he was sick to his stomach. Best guess is that the water in his pack wasn't the best, as he hadn't used it in a long time. On his ride to work this morning, all lit up and wearing a bright reflective vest, he almost got run over by a truck driver who ran a red light and came across both lanes, leaving John little room. Unfortunately, the local police had caught someone else running the same light, so missed the truck.

  6. #6
    Commander, UFO Bike K'Tesh's Avatar
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    So, lets try to work this one out... I've done a full century, with over 6000 ft in elevation gain, and I weigh in at 300+ lbs. (64 miles of those were into a headwind )

    1,800,000 foot pounds

    Cool!
    K'Tesh

  7. #7
    Senior Member LandKurt's Avatar
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    Quote Originally Posted by Lord Chaos View Post
    I've read that human beings put out about 100 watts when resting, so the 100-watt figure for 13mph sounds about right. Anyone can ride a bike at 10mph.
    That 100 watts resting converts to 86 Calories an hour or 2064 Calories a day, which seems like a reasonable base metabolic rate. I've heard when exercising you could burn 500 calories an hour which would convert to 581 watts. How much of that is turned into forward motion on a bike I don't know.

    If you want to take it back to foot pounds: 100 watts is 73.8 foot pounds per second or 4425 foot pounds per minute. Meaning a 300 pound bike and rider is only going to gain 15 feet of altitude per minute at 100 watts of delivered power. A 10% grade at 5 MPH is 44 feet per minute of altitude gain, so you'd need triple that.
    The upside of hills is the downside

    Novara Randonee

  8. #8
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    John gave me copies of his images from this ride. Unfortunately, I can't edit them on this computer, and this forum crashes my computer at home, where I can do the editing. So, I'll have to work out a solution.

    I've read various figures for the amount of power a person can put out. Seems that just about anyone can do 100 watts, on top of their 100-watt basic metabolism, which is why bicyclists tend to go 10 or 12 miles per hour. Beyond that aerodynamic drag adds up in a hurry. Roughly, by feel, it seems that I can do about 17mph on the flat for the same energy as climbing at various rates, but I have no numbers. The hills always vary, anyway. The Amalfi route we rode has a nice flat area about in the middle so you can take a break.

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