Al White, a current member and former president of Evanston Running Club, explained that the biggest hurdle prospective runners often face is the fear that they will be too slow. That fear, he said, is unfounded: “The truth is, though, the people who aren’t running at all are the people who are too slow.”

ERC running sessions vary in venue, length and intensity, from a Wednesday track workout to a longer Saturday run which, during the summer, has water and Gatorade stops along the way. Winter runs attract about 30-35 runners; summer runs draw about twice that many, according to Mr. White.

The club was founded in 1973 by a group of track runners from the Evanston YMCA. They plastered paper notices around town in order to find other local runners. Dues were initially set at $10 a year. Nowadays, Evanston Running Club boasts about 500 members and hosts sessions geared towards runners at all levels, from beginning runners to novice marathoners or marathoners training for Boston.

“When we started running was just for fun,” said Mr. White. “Now the literature is more than conclusive that it’s healthy.”

Numerous members were longtime runners even before joining ERC, and never envisioned themselves being part of a running group. Amy Gingold, who joined in November 2014, was one such member. She joined ERC in to take part in a relay race, but has retained her membership.

“I thought I liked to always run by myself,” Ms. Gingold recalled. “I thought that I like to just do my own thing, and listen to my own music.”

But she quickly warmed to the club’s camaraderie and schedule. “I realized that running with a group made a difference – I was more motivated to get out there when the weather was bad, or it was colder, if I knew there were some people waiting for me.”

“When I was younger, I never ran with others,” added Mr. White. “Now I can’t run unless there’s other people.”

ERC Board Member Tim Guimond recalled that, once when out running alone, he crossed paths with a group of ERC runners who were training for the marathon, and joined the club soon after.

“I didn’t start running until I was age 49,” said Mr. Guimond. “I had been gaining weight, and it was one of those things where I didn’t think I had enough time [to exercise]. … I loved [running]. I went from running for one or two blocks, up to a mile, up to two miles, and the further I went, the more I liked it. I lost 50 pounds and kept it off. I ran my first marathon in 2003.”

Mr. Guimond now leads ERC’s Saturday morning runs.

“Just running with better runners than myself got me inspired to be a better runner,” he explained. “I just enjoyed the life – the camaraderie – and I made tons of friends through running, including some elite people. One example is Nancy Rollins, our track coach on Wednesday nights.”

Ms. Rollins is a veteran of numerous marathons, including this year’s Boston Marathon. In 2007, she won that race’s Women’s 60-69 division.

“She’s a world class runner in her age group,” said Mr. Guimond. “She actually approached me about training with her, especially on the winter runs, when you need a lot of support from people to go outside in the ice and snow.”

Indeed, inclement weather rarely discourages the ERC faithful; Mr. Guimond said attendance starts to dip only when temperatures dip into the low single-digits. “There was one run where I was the only runner in the group. This past winter, I cancelled the Saturday morning run once.”

Numerous members of Evanston Running Club run marathons, both in Chicago and elsewhere. Mr. White estimated that around 400 Evanston residents run the Chicago Marathon, and about 100 of those are ERC members. This year, one out of those 100 will be Ms. Gingold.

“I swore that I would never run a marathon,” she said. “But I was going to the Saturday morning long runs, and running long distances every week, anyway.”

Now well into training season, Ms. Gingold had just completed a 14-mile long run. “I’d done half-marathons before, and never had any reason to run more than that distance. The club makes it a lot easier – it’s nice because there is someone there telling you what to do and who makes sure there’s water.”

Ms. Gingold also credited the ERC with introducing her to a diverse group of people whom she probably would not have had the opportunity to meet otherwise. “I run with everyone from older men to people like Nancy Rollins, who wins her age group in races, to Northwestern Ph. D. students—a lot of times I don’t even understand what their Ph. D. is in. But the club is not just for crazy people who run 10 miles a day – it has both social and motivational benefits. It can be a lot of things for a lot of people.”

Like Mr. Guimond, Mr. White said his health had been improved by running, and his social life had been changed by ERC.

“A lot of people will say they don’t run because of their knees, but those injuries often came when they were younger,” noted Mr. White. “Swimming is less traumatic, but you have to have a pool. But with running you can just put on your shoes and go out the door. You don’t have to just run marathons – you just need to do it for a half-hour two or three times a week.”

More information on schedules and events is at evanstonrunningclub.org.