broken_legs

06-26-2010, 10:22 PM

Soooooooooo

Physics 9 was a LONG time ago for me. I'm trying to figure out how much work/calories I am burning while lifting weights. I know it depends on body mass, metabolism, intensity and all that jazz, but I think I should be able to tell the bare minimum based on the physical WORK I have accomplished, no?

For Example:

One Repetition of a Power Clean:

D = 1.5 m

M = 62 kg

A = Gravity 9.8 m/s2 (not accounting for speed of lift???)

So I remember that

Force = Mass * Acceleration

And

Work = Force*Distance

Soooooo

F = (62kg * 9.8m/s^2)

F = 607 N

(i believe this to be the normal force that holds the weight in equilibrium on the rack, if Im lifting it, im actually applying more force - But for now we'll stick with that to keep it simple)

W = (607 N) * (1.5 m)

Work = 910 NM or 910 Joules

Now the conversion from Joules to Calories is 4.18 so

910 joules/(4.18 joules/calorie) = 217 Calories

So every time I do one power clean I am burning 217 calories???? This cannot be!

Can someone tell me what im doing wrong here?

Physics 9 was a LONG time ago for me. I'm trying to figure out how much work/calories I am burning while lifting weights. I know it depends on body mass, metabolism, intensity and all that jazz, but I think I should be able to tell the bare minimum based on the physical WORK I have accomplished, no?

For Example:

One Repetition of a Power Clean:

D = 1.5 m

M = 62 kg

A = Gravity 9.8 m/s2 (not accounting for speed of lift???)

So I remember that

Force = Mass * Acceleration

And

Work = Force*Distance

Soooooo

F = (62kg * 9.8m/s^2)

F = 607 N

(i believe this to be the normal force that holds the weight in equilibrium on the rack, if Im lifting it, im actually applying more force - But for now we'll stick with that to keep it simple)

W = (607 N) * (1.5 m)

Work = 910 NM or 910 Joules

Now the conversion from Joules to Calories is 4.18 so

910 joules/(4.18 joules/calorie) = 217 Calories

So every time I do one power clean I am burning 217 calories???? This cannot be!

Can someone tell me what im doing wrong here?