In the years I have not run, I missed it. As you have read here, there have been many restarts but nothing sustained. I have too much experience to say that anything as really changed, but I can factually state that I have completed my 67th running workout since the last week of April 2018.
I am building my aerobic base while losing weight at the same time. This translates to a very long period of base-building and very slow paces. I expect to be building until at least the end of the year. I am making measurable progress in both areas. My weight is coming down -- inches off the waist as my resistance training is adding upper body muscle -- and my aerobic base is improving -- faster times with lower heart rates. Keep in mind that "faster" has no relation to "fast" in this case. Let's just say that I cover the same distance in less time with a lower average and peak heart rate.
Building strength, muscle, and endurance -- all still happening in the years past 55. That is good news for all of us. BTW, my resistance training consists of high-repetition dumbbell workouts, using dumbbells over a range of weights from 10 to 40 pounds each (as in, each hand). My workouts now are about 40 minutes and I just hit a total lift of 13,400 pounds (weight times reps for each exercise). Running-wise, I am doing a three-mile LvSD (Long very Slow Distance), walking 2/3 of a mile to cool down, then back into two miles of 100-meter intervals and another cool down walk. This workout takes about an hour and 45 minutes.
I am well-exhausted after these workouts. I run MWF, and lift and do at least 30 minutes on the Nordic-Tack skier on TTh. Just as all the landscaping work held me back from having the energy to workout, now my workouts leave me too tired to do much landscaping. The landscaping is mostly done except maintenance, anyway, which has its widely varying degrees of intensity. My activity priority is fitness now, without being irresponsible toward other tasks.
I have been improving my eating habits (80 percent of weight-loss comes from reducing food intake and only 20 percent from exercise), but I have spent decades cultivating bad habits. Improving these bad habits is good, but I have to face the truth and say that my improvements have only made them less-bad, not good. So now I am working on taking my eating habits from bad, to less bad, to something approaching good (which will likely leave room for further improvement once I get to that level).
Why all this? Do I want to race or do a marathon before I am 70? No. No. I love the solitary runs along country roads. I love to workout. Mostly, though, I love that I feel better about all of my life when I feel like there is nothing holding me back from doing the things I wish to do. I am not trying to add days to my life; I am trying to add more life to my days.