This is well-written and as a runner I agree that running is therapeutic, spiritual even.
My only quibble is tying this to the article’s age angle. The data about older runners competing in Boston and triathlon might conflate correlation and causation. Marathons (especially Boston) and triathlons are both time-consuming and incredibly expensive habits, and the 40-somethings who follow those pursuits have more vacation time and income than their 20-something counterparts.
I also know 20-somethings who use ultra running, crossfit or other sports as a means to combat depression, because it can be such an effective and complementary treatment.
If extreme athleticism works as an effective outlet to help against the existential questions of middle age, that’s great. For any other age, it can also be just as helpful and effective.