She’s been called the Iron Nun and the Nun on the Run, but Sister Madonna Buder says there’s one title that she’s really proud of — the oldest woman ever to complete an Ironman triathlon.

The 80-year-old has been competing in Ironman races since she was 55 and has no plans of stopping now. She says when you think of age, you’re in trouble; if you don’t think about it, you’re better off.

Sister Buder was first introduced to running by a priest in 1978. When she realized she was good at running, she got interested in triathlons. After completing her first one, she was hooked.

Now, exercise is a part of her daily life. She says she jumpstarts each day by running to Mass. She said she swims year-round in an indoor pool and runs and bikes outside the rest of the year, weather permitting.

She’s describing her passion for competing in her new book, “The Grace to Race.” She says when she first started competing in races 25 years ago, it was unusual for a nun and may have bothered some of her sisters. She describes how competing has now just become a natural part of her life.

Plus find out how she digs down deep and endures to complete an Ironman, which consists of swimming 2.4 miles, biking 112 miles, then running a full marathon, 26.2 miles.