Ben M said:
If you want to maintain bone density you should do some running. Running also burns off calories quicker so can help control weight / promote weight loss. The costs are cheaper and in winter, when the roads are getting reguarly dosed in salt, you don't get all those corrosion problems after going out for a run in damp / wet weather. You don't need to take tools / spares out with you, you don't need any mechanical knowledge or skills. And based on observations, my dog would disagree with you - she never gets excited when I come down the stairs and put on my cycling shoes, but see when I put on my running shoes - she bounces off the walls with sheer joy in the knowledge that she'll get to come with me for a run.
