Bike on a treadmill...
09-26-13, 08:58 AM
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Bike on a treadmill...
Since the budding physics majors have exhausted themselves in the 400W thread, here's another question:
How much power does it take to pedal on an inclined treadmill?
a) depends on speed of treadmill and bearing and frictional losses only so same power as flat treadmill.
b) equivalent to riding outdoors on the same incline.
How much power does it take to pedal on an inclined treadmill?
a) depends on speed of treadmill and bearing and frictional losses only so same power as flat treadmill.
b) equivalent to riding outdoors on the same incline.
09-26-13, 09:34 AM
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Easy ....... 327.683 watts (I don't have to show my work, do I ?)
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09-26-13, 09:56 AM
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Neither A nor B. A ignores the fact that you're functionally fighting against gravity and B ignores the fact that there is no wind resistance.
I say the best thing is for you to test this and video it.
I say the best thing is for you to test this and video it.
09-26-13, 10:00 AM
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09-26-13, 10:01 AM
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09-26-13, 11:53 AM
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B. (same incline at same speed). You essentially are doing work against the belt and putting power into the treadmill. The treadmill's motor will have to work less hard to power the belt or may even need to provide braking so that the belt doesn't speed up.
09-26-13, 01:16 PM
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Lack of forward motion means lack of wind resistance. They're not the same at all.
09-26-13, 01:22 PM
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Interesting question. I don't think it will be equivalent to riding up the same grade. The sine of the angle times your body weight is going to be the force pulling you down the incline. So as you ride you need to counteract that force to stay stationary. The speed your wheels are spinning shouldn't affect this much.
09-26-13, 01:26 PM
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Divide everything by four.
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09-26-13, 01:35 PM
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1.21 gigawatts.
09-26-13, 02:00 PM
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09-26-13, 02:02 PM
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09-26-13, 02:16 PM
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I had always wondered what it would be like to ride on a treadmill. After seeing this video a couple years back, I never thought about it again. Does anyone really ride on a running treadmill?
09-26-13, 02:46 PM
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Interesting question. I don't think it will be equivalent to riding up the same grade. The sine of the angle times your body weight is going to be the force pulling you down the incline. So as you ride you need to counteract that force to stay stationary. The speed your wheels are spinning shouldn't affect this much.
09-26-13, 03:40 PM
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09-26-13, 04:24 PM
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Since the budding physics majors have exhausted themselves in the 400W thread, here's another question:
How much power does it take to pedal on an inclined treadmill?
a) depends on speed of treadmill and bearing and frictional losses only so same power as flat treadmill.
b) equivalent to riding outdoors on the same incline.
How much power does it take to pedal on an inclined treadmill?
a) depends on speed of treadmill and bearing and frictional losses only so same power as flat treadmill.
b) equivalent to riding outdoors on the same incline.
09-26-13, 04:33 PM
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Neither. You have to have to lift your weight relative to the treadmill's moving surface and overcome friction as you do outdoors but only have aerodynamic drag from the spinning wheels and not moving through their which is less than outdoors because the top of the tires is moving at the treadmill speed not double the road speed.
You could, of course duplicate the aero effects if you were riding in a wind tunnel or had a big enough fan
09-26-13, 05:16 PM
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log rollers
Last edited by MikeyBoyAz; 09-26-13 at 05:21 PM.