Joe Datsko, 92, of Catonsville, Md., became a serious bike rider in the 1970s. He estimates he has logged about 150,000 miles in his lifetime.

BALTIMORE — Joe Datsko was an admitted workaholic for the first 25 years of a 47-year career as a mechanical engineering professor at the University of Michigan. Datsko likes to say that until he was in his early 50s “most of my exercise was writing on a blackboard.”

That changed in the early 1970s when the younger of Datsko’s two sons — he also has three daughters — was invited to the 1972 U.S. Olympic trials in cycling. Robert Datsko, who was in high school at the time, failed to secure one of the 12 spots, finishing in the top third of the 66-person field.

But something happened to change Joe Datsko’s life.

“We became a bicycling family,” Datsko, 92, recalled recently, sitting outside his apartment at Charlestown Retirement Community in Catonsville, Md., where he now lives.

Datsko, who as a college student at Michigan once rode a three-speed bike from Ann Arbor to his hometown of Ebensburg, Cambria County, became the most serious cyclist of all.

The Tour of the Scioto River Valley, or TOSRV, in Ohio, a 210-mile back-and-forth trip between Columbus and Portsmouth, became an annual excursion that eventually doubled as a family reunion.

And Datsko became one of the most dedicated riders in the Ann Arbor Bicycle Touring Society, a local riding club founded by his older son, James, and some friends.

“When I retired in 1990, there was a lot of publicity about celebrating 500 years of Columbus coming to America, and I thought it would be great for me to ride cross-country like my daughter had done,” Datsko said.

Datsko was one of 45 who, with a Minnesota-based cycling club, started off in Bellingham, Wash. Then age 71, he was one of only six who rode every inch of the more than 5,200-mile trip that ended 12 weeks later in Portland, Maine. Fifteen riders dropped out after the first week.

“I didn’t know if I could do it. I hadn’t ridden in the mountains,” Datsko said. “My younger son was a captain for American Airlines, and I had an open ticket for a return flight for any weekend if I couldn’t handle it.”

Datsko was the oldest in the group by two years to start the tour and the oldest to finish. He followed up with a ride the next summer from Portland, Maine, to Orlando, Fla. — a mere 1,680-mile jaunt. He took another cross-country trip, from Oceanside, Calif., to St. Simon Island, Ga., in 1994.

After his children moved away from Ann Arbor and his wife, Doris, died, Datsko’s life centered on the local cycling club. Three years ago, he became the first member to ride 100,000 miles around the college town. Overall, in his lifetime, he estimates his total is 150,000 miles.