Here’s an article on why you shouldn’t run. I don’t recommend reading it, it makes the assumption that everyone’s main aim in life is to lift heavy weights and have big muscles.
Reason 2 of ‘why you should not run’: Endurance training is directly antagonistic to the creation and retention of muscle mass.
I think it’s interesting that people equate muscles with fitness. From an evolutionary perspective, having huge muscles is a huge waste. They require a lot of resources, and that inherently puts you at a disadvantage. My suspicion is that our ability to build huge muscles with strength training represents a lack of evolutionary optimisation, which suggests that that sort of heavy lifting has not ever been very important to our bodies. I also disagree that big muscles are particularly strongly correlated with practical strength. Look at a yoga instructor. They are capable of both a lot of strength and a lot of muscle control, which is very useful in every-day life (far more useful than being able to bench press 300lb), but visually, their muscles tend to be ‘toned’ at best.