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Measurement for force, distance and time for a treadmill

  1. Apr 3, 2005 #1

    I'm trying to find "good" measurement for force, distance and time for a treadmill. I'm assuming the force will simply be the "weight" of my body but the distance..the distance is a different issue altogether.

    Since we're contrained in not using the data from the machine, I must use simple devices in my disposal i.e. metre sticks, bathroom scales, stop-watches, etc.

    How would I calculate good "distances" assuming I'm not setting the treadmill on an incline (that is, if I don't "have" to set it on an incline).

    Can I just calculate the average distance between my legs and multiply that by the number of steps I take?

    I must also calculate...

    1). Energy conducted away by vaporizing sweat.
    2).Energy that has been radiated away by my body during the workout.
    3).heat energy stored in excess body temperature.
    4). Amount of heat energy lost by convection
    5). total food energy used
    6). heat energy created during the work-out.

    Also, what happens to the energy stored as excess body heat as my body cools down to normal temperature?

    Any help would be appreciated. Thanks.
  2. jcsd
  3. Apr 4, 2005 #2


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    Staff: Mentor

    Since you're bouncing up and down and the angle between your legs and the ground varies, its proably a lot more complicated than that. [if you're running] I think you need to construct an equation taking into account the changing angle between your leg and the ground and the resultant forces, then add the energy used when you bounce. Remember, work is force times distance and that force and distance need to be in the same direction - but your weight is vertical and your walking/running is horizontal.

    The power from bouncing is easy - it is your weight times how high you bounce times how often you do it (and multiply by 2 since you have to accelerate to get up and accelerate again to stop when you hit the ground).
    The distance you run is the easy part. You've heard of a pedometer, right? Just count the number of paces you take on a closed course and calculate the length of your stride.
    Once you have a good measure of your pace, yep.
    Weigh yourself before and after. Collect unevaporated sweat (eww).
    You mean convected (radiated heat is virtually nonexistant for a person)? That's difficult - a little bit of wind makes a big difference. The vast majority of the heat loss comes from sweat though.
    Little to none.
    Well, that's what you're calculating with the above.
    That's what you're calculating above.
    Someone correct me if I'm wrong, but the body's core temperature remains at 98.6 - the distribution changes as more blood is pumped to the extremities to dissipate heat (ie, your skin gets warmer). The amount lost in cool-down is the same as the amount gained in warm-up, so you can just ignore it and work off of steady-state heat flow once you're warmed up.

    Similarly, while your heart and breathing may take an hour to return to its normal rate, that's because your body needs to "catch-up" with the fuel (both food and oxygen) lost during the workout.
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