Doing lots of exercise in older age can prevent the immune system from declining and protect people against infections. Scientists followed 125 long-distance cyclists, some now in their 80s, and found they had the immune systems of 20-year-olds. The research was published in the journal Aging Cell.

I dont know for me the benefits are short term also, but then again it doesn't feel like it until after you're done so getting to that point people get hung up on until you've been doing it long enough that you associate the uncomfortable nature of exercise with the good feelings you know are coming then it becomes somewhat of an addiction to those feelings. I can't understand in my own mind why people don't want to exercise. Anytime I've stopped I start to feel depressed, sore, anxious, my confidence drops, my hormones go out of whack, and so it's not an option to stop however it did take a few months (to maybe years) to not FORCE myself into it.. now I crave it so it takes a lot of discipline at first until you associate exercise with the good feels

/r/science Thread Parent Link - bbc.com