‘Fitness’ — literally comes from ‘fit‘. A theory on the origin of the word ‘fit’ comes from the Middle English ‘fit’ which means ‘an adversary of equal power’.

Thus perhaps in some ways for us men who are trying to become more ‘fit’ — what we are actually trying to *really* do is to become more physically dominant than the other man, in order to exert our strength and dominance over them.

But anyways in the modern sense in terms of ‘physical fitness’ (a modern notion which only comes from around the 1920s onwards) — why fitness?

To look great, to feel great

Vanity is good. Certainly when it comes to physical fitness, the more buff we are, the less body fat we got, etc … the better we feel about ourselves when looking in the mirror. And even assuming there weren’t mirrors around, the benefit of having less body fat and more muscle mass is:

1. You get less hot and ‘overheated’ when outdoors or in humid environments
2. You have more physiological energy
3. You generally feel greater

And of course we got a trillion mirrors around the house. When you take off your clothes and get naked in front of the mirror when you shower, don’t you want to like what you see?