Re: [Phys-l] treadmill vs open road

[Hugh Haskell <hhaskell@mindspring.com>]

At 08:31  -0400 5/9/08, Brian Blais wrote:

> I can think of no difference in the physics between the
> two systems which would give rise to the different experiences.

How about this. On a treadmill your upper body undergoes essentially 
no horizontal motion or acceleration, so your legs are essentially 
required to move only their own mass and not the mass of your upper 
body. Thus running on a treadmill is less work than running on a road 
or track.

I'm not a runner of any sort, but I have used a treadmill on occasion 
for walking exercise, and I find that I can sustain a considerably 
higher rate of "motion" on a treadmill than I can when walking, even 
on a level path. On a treadmill, the "normal" walking speed of about 
2.5 mph seems quite slow, and I can easily maintain a speed of close 
to 4 mph--one that would leave me panting and exhausted after a short 
time on a walking trail.

Hugh
--

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Hugh Haskell
<mailto:haskell@ncssm.edu>
<mailto:hhaskell@mindspring.com>

(919) 467-7610

Hard work often pays off after time. But Laziness always pays off now.

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