Long term (and I mean LONG TERM) exercise!

Define "advanced age"...

If I had to generalize - I'd say think in terms of low impact versus high impact (cycling and swimming versus running), and exercises/sports that don't require a lot of quick changes of direction (rowing versus basketball).

That said, there will be numerous exceptions to this rule, of course...

I have several mfp friends who are fit/active and in their 60s and even early 70s. One in particular lifts heavy even with ill health. I suppose where there's a will there's a way?

I know several 70 yr olds who cycle regularly 60+ miles at a time.

Cycling is easy on the joints

I ride, I golf, hunt and fish with my sons, and I work my farm with all the hard work that comes with it like clearing brush, chainsawing, digging, etc.

It might kill me one day, but at least I lived my life not cooped up in a house, inactive and overweight, looking at the idiot-tube and watching 1/2 hour of commercials for every hour of TV (although I used to do that - but no more).

I'm a cyclist and hang out with a lot of other cyclist and my trainer works with a lot of cycling enthusiasts. One of his clients is in his late 70s and he lifts and rides...he's not doing power lifting or anything like that, but he lifts and he rides regularly...he's actually doing the time trial series this summer.

There are a lot of people in my circle of cycling friends who are in their 70s and a few in their 80s...and they aren't just casual joy riders, these folks are still doing 1/2 centuries and the like.

My 91 year old grandma still goes to the Y to participate in aerobics classes 3 days per week. I would love to be like her!

Old is also a state of mind as well as calendar years - I work with a lovely guy who is a couple of years younger than me, he's fat, had a triple bypass, diabetic and acts so damn old! Never does any exercise, barely active really, only started to take care of his diet after becoming diabetic. Sadly I can't predict a long and healthy old age for him.

My health, strength and fitness are precious to me and I invest the time and effort accordingly. Neither of my parents had the retirement they deserved and that motivates me.

Started weight training in 1974 as a reaction to a bullying culture at school and can't see the time I will ever stop. There's a perverse satisfaction in lifting more than old farts are "supposed" to that tickles my funny bone. Also suits my self-competitive nature.

Cycling is my other big thing, part as a personal challenge to improve but it's also kind on my knackered knees and takes me to wonderful places. I'll need a knee replacement one day but that should only be a hurdle to overcome rather than a full stop.
I see loads of 70+ cyclists doing endurance events and they are a great inspiration, both because they are still doing it and also because of the obvious benefits to their quality of life: mental, emotional and physical.

Growing old gracefully my *kitten*!
Growing old disgracefully FTW.

I'll be 65 next February. I'm always shocked when I think about my age because I don't feel old. When I exercise, I vary my activities. When I work out on my elliptical , I work out for 55 minutes, I have several step aerobic routines I do on a regular basis, I walk my dog, I walk up and down 7 flights of stairs at work 5 days per week (350 steps up and 350 steps down). I try to do cardio of some sort 5-6 days per week. I also don't consider it a good workout if I'm not drenched in sweat at the end of the workout. I do strength training 3x per week using dumb bells and resistance bands. I'm looking forward to retirement next year so that I can kick it up a notch. I'll let ya' all know when I get "old". Gotta' go, it's time to jump on the elliptical.

For the sake of argument, I am going to consider over-50 years as old age.
My wife, who is 51, runs. In the past few years, she has run at least four marathons, and now, in the past year, she has been injured for most of the year, with slightly different ailments, mostly related to a stiff and achy, lower back.
My point is: Many of us tend to get locked in to one type of exercise that we like to do, and after a while the toll from doing the same thing over and over begins to add up. Sometimes the key to staying active long is to recognize this fact.
I have been trying to talk my wife into doing something different -- preferably something with a bit less pounding -- for at least six months. Maybe rowing. Maybe biking. Let the tissues rest. Let the little things heal. You can go back. But sometimes you have to rest from a repetitive motion.
I remember hearing Serena Williams say one time that she felt that one of the reasons she was still going strong at the advanced [ahem] age of 33 years (then) was because she was injured for a year and the time off allowed her body to rest.
I think the older you get the better off you are if you mix it up a bit.

I plan to be that fit, crazy 80 year old they make meme's about...Weights, cardio, the works....I live by the adage "Use it or Lose it"!

I belong to a medically oriented gym and I seem to be the youngest person there. I'm 47. Most are in their 70-80's. They use the weight machines, treadmills, free weights, etc. Some are there because they have injured themselves, but there are a lot of them there for their health and strength.