Back when I was still physically able to run, I did so. A lot. Sometimes I would describe that day’s run on Facebook. Once when I did, a friend jokingly asked, “Who was chasing you?” My answer: “The aging process.”

With another birthday upon me, I am thinking about how my celebration has changed. In my early 30s, I finally accepted that I’m not immortal and began to get serious about taking care of my health. My primary form of physical exercise was running. Soon, I started entering road races as incentives to run regularly. Over time, running regularly became its own incentive.

I decided I would mark my 33rd birthday by running a mile that day and I would add another mile each year to my 40th birthday, on which I would run eight miles. I knew it would take some work to increase the distance I could run, but surely I could get from one mile to eight miles, gradually building up my strength over that many years.

I ran two miles on my 34th birthday, three on my 35th and so on to eight miles on my 40th. Exactly as planned.

It didn’t take me eight years to work up to being able to run eight miles, though. In fact, I ran a half marathon a few months before my 36th birthday.

After 40, I did not keep adding miles to my birthday celebration. For my 41st, I ran for 41 minutes, then 42 minutes on my 42nd. I don’t remember how many years I continued this specific plan, but for a number of years I came up with something along these lines.

I also don’t remember when I began letting my birthday be a day of rest and relaxation. Probably around 60, which is when my knees began to complain. I still exercise regularly and at a level appropriate for a septuagenarian, but I take my birthday off now.

I’m continuing to run from aging, mostly via a bike in the gym, but certainly not from birthdays. Continuing to have — and enjoy — birthdays is kinda the point.