Hello.

This is probably quite basic, but it's been a bit more than 20 years since I studied math/physics, so that's why I turn to you guys. I am trying to figure out how to calculate the energy consumption during weight lifting.

I guess there's five calculations;

- Lifting a weight in a straight line
- Lowering a weight in a straight line
- Lifting a weight with a circular motion
- Lowering a weight with a circular motion
- Holding a weight in a fixed position

I

*think* I got the first one right.

Using these definitions,

- Mass (m) = 90 kg
- Distance (h) = 0.48 m
- Gravity multiplier (g) = 9.82
- Joule (J) to calorie (cal) multiplier = 4.2

I get this;

$\displaystyle J = mgh = 90 x 0.48 x 9.82 = 424.224$

$\displaystyle cal = J/4.2 = 424.224/4.2 \approx 101$

*(However, I am uncertain of this as it sounds quite a lot to use 101 calories to lift 90 kg 0.48 m, compared to, say, about 500 calories by running for 20 minutes.)*