Curious about amount of calories burnt during my weight lifting routines.?!
Question: I just need a educated estimate of calories burnt during a 45-55 minute medium to high intensity workout. Im sure my weight factor helps so ill tell you i weight 155 lbs. Also im 15 if that does anything.
Thanks in advanced
Answers: I just need a educated estimate of calories burnt during a 45-55 minute medium to high intensity workout. Im sure my weight factor helps so ill tell you i weight 155 lbs. Also im 15 if that does anything.
Thanks in advanced
The number of calories exerted to move any weight can be estimated using the formulas for work and force along with a few simplifying assumptions.
Work is measured in joules. 1 joule is equal to about 0.239 calories. By calculating the work required to lift the weight, you can calculate the number of calories required to do that work.
work (joules) = force (newtons) * displacement (meters). This equation assumes that you lift all of the (free) weight straight up. No machines, no pulleys, etc.
force (newtons) = mass (kg) * change in velocity/time (m/sec/sec)
There are 2.2 pounds in a kilogram, so 100 pounds is about 45.45 kgs. If you move 100 pounds (45.45kg) 1 meter in one second, use the joules to calories conversion and do 10 reps you would exert 109 calories as shown below:
45.45kg * 1m/sec/sec* 0.239calories/joule * 10 reps = 109 calories
If you move half the weight in twice the time over the same distance -
22.72kg * 1/2m/sec/sec * 0.239 calories/joule * 10 reps = 27 calories
If you are doing bicep curls you might move 25 pounds (11.4kg) about 1 foot (.3m) in 2 seconds
11.4kg*.3/2 m/sec/sec * .239calories/joule * 10 reps = 4 calories
If you squat 220 pounds and moved the weight about 16 inches (.4m) in 4 seconds
100kg * .4/4 m/sec/sec * .239 calories/joule * 10 reps = 24 calories
Your body weight should be included in the weight you lift, over the distance that you lift it. Other than that, your body weight doesn't matter.
Absolutely no way of putting a number on it.
More than watching TV, less than running for the same amount of time.
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Note to Jim: In this case, misleading and not terribly relevant. It doesn't take into account the questioner's mechanical or digestive efficiency, and your formulas reference calories, not kilocalories (Calories with a capital "C") , which are the unit of measure generally used in the context of exercise and diet.