Nearly 80 runners gathered on the steps of the Malkin Athletic Center (MAC) Wednesday afternoon for a celebratory jog along the Charles River with authors and fitness authorities Scott Jurek and Christopher McDougall ’85, in an event coordinated by Harvard On The Move.

Jurek is famous for dominating ultramarathons, endurance events that well exceed the traditional marathon distance of 26.2 miles. In 2010, at the 24-Hour World Championships in Brive-la-Gaillarde, Jurek ran 165.7 miles in 24 hours, setting a U.S. record. He is also author of the book “Eat and Run: My Unlikely Journey to Ultramarathon Greatness.”

McDougall is the author of “Born to Run: A Hidden Tribe, Superathletes, and the Greatest Race the World Has Never Seen.” He rekindled his love of running after studying the seemingly superhuman running techniques of the reclusive Tarahumara Indians of Mexico’s Copper Canyons.

After the run, the Harvard Book Store hosted a discussion featuring Jurek and McDougall at the Brattle Theatre.

Standing outside the MAC earlier, McDougall pointed toward the Yard. “When I was at Harvard, I was in Winthrop House,” he said. “Part of what got me through school was just playing here in the Yard, chucking around a football, just having some playtime. Running’s like that; you just head out and play.”

For Jurek, the gathering on National Running Day was an opportunity to celebrate such exercise as a social, community event. “I love to get out and run with other people,” he said. “I’ve run a lot of miles by myself, and people ask me why I come out for group runs. But we love that social aspect. When I’m running with others, I feed off their motivations and stories, how they got into running, and so on. It inspires me and keeps me going.”

Obi Okobi, who just graduated from the Harvard Graduate School of Education with an Ed.M., said she came out to jump-start her commitment to running. “Harvard On The Move really is a fantastic entity,” she said. “It proves that the School is really looking to model wellness, not only for undergraduates, but also for members of the greater Boston community.”

Jill Puleo, owner of Sugarbird Bakery in Rhode Island — which bakes “ultracookies,” a gluten-free treat for ultramarathoners — drove up just to participate in the event.

Proving that running wasn’t just for students was 78-year-old Brookline resident Henry Wolstat. “I’ve been running for about 40 years,” he said. “It keeps me young, it keeps me alive, and I try to run every day — about 25 miles a week.”

For Daniel Lieberman, Harvard professor and chair of human evolutionary biology and principal investigator for the Skeletal Bio Lab, the diversity of those attending spoke to the mission of Harvard On The Move. “We have runs and walks every week for people of every ability, speed, and distance. Running is a communal thing. People have been running together for millions of years. It’s just a way for people to get out and get moving.”

As the group headed through the Winthrop House Gate toward the Charles, McDougall smiled. “Running’s playtime,” he said. “All the anxiety and the hectic things in your head, they just clear out. And you come back feeling relaxed and ready to tackle the next thing.”

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