Our landline rarely rings unless it's a robot or someone in Bangalore wanting to clean my ducts or fix my Windows computer. (I have radiators and a Mac.) But this was a human voice I recognized, saying "I died the other day, but they brought me back!"

It was an old friend I'll just call P, who worked for me when I was an architect. He married my receptionist. He was best man at my wedding and after I became a developer, he became my architect on a big project. We had a falling out at some point; it was either over work or over a piano, I cannot remember. We hadn't spoken for years.

Last week he was not feeling well when he went to bed, and felt worse in the morning. At one point he just got up from his desk and said "I have to go to the hospital." While he was sitting there with two nurses and a doctor, he had a massive coronary and fell to the floor with zero heartbeat, zero blood pressure. The nurses started CPR and the doctor ran for the paddles and they brought him back. He notes that if you're going to have a major heart attack, the smart thing is to do it in the emergency ward. He also invited me to visit, which I thought odd, since we really hadn't talked in a very long time.

I've many thoughts about this. The first is about exercise; many years ago, P said he didn't believe in it. Astronaut Neil Armstrong summarized the argument: “I believe that every human has a finite amount of heartbeats. I don't intend to waste any of mine running around doing exercises.” He's not alone in this view; President Trump shares it. According to The Atlantic, the president gave up sports after college because he "believed the human body was like a battery, with a finite amount of energy, which exercise only depleted."

When P suggested it years ago, I fired up VisiCalc on my Kaypro II and did a big spreadsheet showing that because my resting heartbeat was so much slower due to my running, that even with the extra beats during exercise, my aggregate total of heartbeats was less than his. I didn't remind him of this when I was at his hospital bedside.

Meanwhile, on the day I saw him, Gretchen Reynolds wrote in The New York Times about how "aerobic activities like jogging and interval training can make our cells biologically younger."

There is mounting and rousing evidence that being physically active affects how we age, with older people who exercise typically being healthier, more fit, better muscled and less likely to develop a variety of diseases and disabilities than their sedentary peers.

Cuyahuga River There is a path along the shore here somewhere, but this was where I went running — because on this particular morning, I had to run. (Photo: Lloyd Alter)

The next morning I was out of town on a trip to Kent, Ohio, but got up early to go for a long run along the Cuyahoga River and became determined that I'm not going to miss a day of exercise, no matter how crazy my MNN and TreeHugger deadlines are.

After you exercise, you're not done

The other lesson of this experience is the issue of friendships, of relationships. I thought about who I might ask my wife Kelly to call if the same thing happened to me, and the list of people I truly think of as friends was extremely short. Sometimes I fear that I'm closer to people on Twitter and Skype than I am to people I know in person. This isn't healthy.

Wall Street Journal cover This guy is my age. (Photo: Snapshot of Wall Street Journal page)

Also on the same day as my visit to P, there was an intense article in the Wall Street Journal,The Loneliest Generation: Americans, More Than Ever, Are Aging Alone. The first person in the article is my age.

Danny Miner, a 66-year-old retired chemical plant supervisor, spends most days alone in his Tooele, Utah, apartment, with "Gunsmoke" reruns to keep him company and a phone that rarely rings.

He looks ... old. He is on oxygen, sees nobody, goes nowhere, has no friends.

Now the only family Mr. Miner sees regularly is a brother who stops by every few weeks to cut his hair. His main outings are trips to the VA hospital in Salt Lake City for cortisone shots in his sore shoulders and checkups for emphysema and diabetes.

It seems in so many of the examples in the article that health and loneliness are intimately connected. And while I might trot out my old arguments about aging in the suburbs, this isn't just about urban design, it's universal.

So much of this is chance; you don't get to choose your parents' genes or wealth. You don't know what random thing life will throw at you.

family Reunion The Alter family reunion in Arizona — a fun time and a reminder that showing up is almost always the right choice. (Photo: Lloyd Alter)

But the events of the last week have convinced me that when the things we can control swing around, it's so important that we grab them. I've already started reconnecting with P and his wife, and I'm going to think about other friends and family where I've let connections loosen and fade. I'm going to run or row every day. I'm going to seriously watch what I eat and drink.

It's not the first lesson I have learned from my old friend P, but I'm taking this one very seriously.

Lloyd Alter ( @lloydalter ) writes about smart (and dumb) tech with a side of design and a dash of boomer angst.

There are 2 keys to successful aging: Exercise and friends
Health and loneliness are intimately connected and you have to work on both.