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I am doing 5x5 with current squat weight of 275 lbs (body wight 194lbs)

Just calculated how much energy it takes to move such weight over 4 feet (approximate distance for my 6ft height) from the ground against gravity

It seems that 25 squats require 9000 calories to perform. It can't be right, since I eat like 3000 calories a day. Is there mistake in my math?

Math on WolframAlpha

Math: 4 feet distance, 4100 joules per 1 kilocalorie

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    Any chance you're getting your calories (cal) and kilocalories (kcal) mixed up here?
    – Alec
    Dec 21, 2017 at 19:09
  • @Alec yes! Calories=kcal=1000 metric calories Dec 21, 2017 at 21:25

2 Answers 2

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Work = M * G * H

M being mass, which would be 125 kg(~275lb), although it would be slightly more as you are also squatting part of your bodyweight. Lets say 170kg G being Gravity, which for the formula is 9.8 meters H being height, we will say 1.5 meter (~4.5 feet, 3 feet on way up and we will say 1.5 feet down as you're moving with gravity so not as much energy is needed)

=125 * 9.8 * 1.5 = 2499 Joules Since 1 joule is equal to 0.000239006 kilocalorie, you would burn about 0.60 kcal per rep.

0.6 x 25 = 15 calories.

This doesnt seem right either, as I would imagine you would burn bit more calories per squat, but its closer. This is also effected greatly by your weight, metabolism, what your heart rate is while squatting, ect, ect.

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    muscle efficiency is only at around 20%: en.wikipedia.org/wiki/Muscle#Efficiency
    – BKE
    Dec 21, 2017 at 21:10
  • there was confusion with units. We need 2,500kcal a day, so squats at most require 15kcal or 0.6% daily energy Dec 21, 2017 at 21:20
  • As a side note - if I take a brick and move it at exactly same level, for let's say 1km - the work is zero. No move against the force... That is why physics not always works here, a specially that calories, but that is a bit different story. Dec 22, 2017 at 14:40
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Here is real answer: person consumes 2500 kcal, which is 2500*1000cal. Hence squatting, even if it takes 9000 cal, is just 9kcal or 0.36% daily norm. This stems from confusion between calories, kcal, and Calories=kcal.

From Wiki (bold is mine):

The word calorie is popularly used with the number of kilocalories of nutritional energy measured. As if to avoid confusion, it is sometimes written Calorie (with a capital "C") in an attempt to make the distinction, although this is not widely understood. Capitalization contravenes the rule that the initial letter of a unit name or its derivative shall be lower case in English.

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