Muscle, fat, density, weight, mass...oh my!
As a mechanical engineer, I find it upsetting the lack of understanding in basic scientific principles on the forums. I know people are just going to say "get over it" or "what's the big deal?" However, if people do not understand basic science then the perpetuation of fads, misinformation and outright lies in the fitness industry will continue. As an example, one concept that comes up a lot is the difference in the density of fat and muscle.
It usually goes something like this: Someone says "muscle weighs more than fat." Another person points out this is wrong because "a pound equals a pound." This person goes on the explain that "muscle is less dense than fat." Then the arguments start about nitpicking, context, etc. Underlying all the bashing and arguing is the unfortunate reality that both "sides" usually lack a complete understanding of basic physics.
Let's break down some of these statements:
"Muscle weighs more than fat" - This statement is more incomplete than inaccurate. It's incomplete because there is no frame of reference stated. A more complete statement would be "At sea level on Earth, an equal amount of volume of muscle weighs more than an equal amount of volume of fat at the same pressure and temperature."
"Muscle is more dense (sic) than fat" - Another incomplete statement. Again, there is no frame of reference. A better statement would be: "At the same pressure and temperature, muscle is denser than fat."
"A pound equals a pound" - This one irks me because it demonstrates the root cause of the misunderstanding of the general topic. Again, it's a frame of reference problem. Unfortunately, in the English system of units, "pound" is used interchangeably between weight and mass suggesting that weight and mass is the same thing. This is a false. In the scientific and engineering fields we distinguish between mass and weight by using either lbm or lbf, respectively. One pound-mass (lbm) is a unit that measures the amount of matter in a given object. It is always the same no matter where you are. So a true statement would be "1 lbm equals 1 lbm." (There is a disclaimer here because some of these rules break down in the quantum world, but I will admit myself that I do not understand a lot of that crazy stuff). One pound-force (lbf) is a unit that measures the amount of force gravity is exerting on a mass. A true statement would be "at sea level on Earth, 1 pound-force of muscle weighs the same as 1 pound-force of fat."
Again, my goal here is not to bash people, nitpick, or try to be all pretentious. I just want people to start understanding BASIC science! If more people understand science, the lies, misinformation and deceit the diet and fitness industry tries to use on us will not work as much and we can all start having a healthier relationship with food and exercise.
I apologize in advance for what is to come next, but it needed to be said…..
Let the games begin!
