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Old 08-20-09, 09:45 AM
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LandKurt
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Originally Posted by Lord Chaos
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.
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