I was advised tonight that running ruins your knees. It must be true because the man said he knew lots of people who ran, played rugby or football whose knees were damaged as a result. I advised him that I will be avoiding rugby and football but that running has only improved my fitness. When asked who he knew who ran with damaged knees, he said his brother who was a "professional" runner. Oh that's ok then, I am not a professional runner, I do it for my own enjoyment, I run three times a week and over shorter distances. If I have any issues with my legs, I rest them but in fact they are stronger than before. What a twerp! He has asthma so couldn't possibly run - oh and my lung capacity is also improved - I managed to keep it to myself!! Anyone else have concerned people warning them to stop running?