I've been running a consistent 10-11ish kilometers 5 times a week for the last 13 years. Recent (old) re-injury has forced me to switch to weight training about 6 times a week - and absolutely loving it. I'll probably switch to something like Crossfit next year to take up a more cardio-routine, but it's showed how you don't need to necessarily "run" to stay fit & healthy (although I do miss it a lot).