Find some 20 years old cars, one with 200,000 miles on the clock, one with 20. Which would you choose?
Mechanical parts wear out from use, whether they are animal or machine. Animal parts will heal to an extent and may require a minimum level of use to stay healthy, but they still wear out.
If I go lift heavy weights, my bones self repair and get stronger.
If I sit on my butt all day on a computer, my bones get thinner and weaker.
No matter how much you drive a car, it is never going to get "stronger", only slowly wear out.
Since you are a human and not a car, I would suggest you maintain your body like it is alive and not made of metal.
As to the general feeling here. I invite everyone here who thinks ridiculous exercise is good to volunteer at an emergency room for a week. I guarantee this idea will get cured on the first day in any large city.