APF -
You can't be in long-term medical care (meaning, in a hospital or old folks' home or similar) and simultaneously be jogging. How many folks do you see rise from a wheelchair for a brisk morning 5k? An 'active, sporting lifestyle' is no panacea but by no means is it something we should be discouraging because of minor injuries. The long-term savings are going to far outweigh the short-term costs.
Are you familar with the term 'organ reserve'? It's basically the capacity of our organs to handle stress. Dying of 'natural causes' is typically because of organ failure. Organ reserve correlates strongly with skeletal mass and lean muscle mass. The more exercise you do, the more you build up your bones (yup, lifting weights literally gives you bigger bones, since your body is responding to the stress of carrying the extra weight...hence the common fattie defence of being 'big-boned'), your muscle mass AND your organ reserve. Anyone who is taking regular exercise is on track to live longer on average than people who don't, and have a higher quality of life while doing so. They'll be getting up and walking around, picking up heavy stuff etc much longer than couch potatoes BECAUSE they get up, walk around and pick up heavy stuff right now. Any mentality that discourages people from being active and sporty now is working against our shared long-term health interests. I recognize that the original statement about this was intended to be satirical but it's still wrong-headed and uninformed.