Nothing stops David Berdan from his daily running regimen.
Either in between, before or after teaching science to fourth-, fifth- and sixth-graders at Garrison Forest School, Berdan is likely to be wearing out another pair of running shoes as he takes a daily run of, on a slow day, anywhere from an hour to an hour and a half.
That's in addition to time spent with his wife, Amanda, and sons Colin, 3, and Evan, 8 months.
Or coaching the Grizzlies' varsity cross country team to a surprising second-place finish in the Interscholastic Athletic Association of Maryland C Conference championship meet.
"Dave is the consummate teacher, husband, coach and father," said Garrison Forest athletic director Traci Davis. "He does all that and is still an elite runner. And the fact that he's doing it at that level against professional runners, is even more amazing."
When Berdan, 30, focuses on long weekend runs, he piles up mileage required by all top marathoners.
For instance, as the campus resident prepares to run past the Betsy Ross House and the Liberty Bell in the Philadelphia Marathon (26.2 miles) on Nov. 20, he sets a mean pace on a 20-mile jaunt that only the best of the best distance runners would even contemplate.
After a 2-mile warmup at a moderate rate, Berdan hustles through four, 3-mile sets at a 5:10-5:15 pace, with a 5:40 recovery mile between each set. After a couple of cooling-down miles to finish the excursion, even he is ready to get off his feet after such a strenuous workout.
"I really have to make sure I get rest on the long days," said Berdan, who was an All-American 5k and 10k runner at Elizabethtown College in his native Pennsylvania.
He hopes the road work will help him record a sub-two-hour, 19-minute marathon in Philadelphia, which would be two minutes faster than his 10th-place finish (2:21:19) in the Baltimore Running Festival last month and qualify him for the U.S. Olympic Trials in Houston in January.
"I think I can do it," he said. "If I run as well as I did in Baltimore (marathon), I should be fine. The course is a lot flatter than Baltimore's."
Should that happen, Berdan has no illusions about earning a spot on the Olympic team that will take the top-three finishers from the trials.
"Realistically, I won't make it," he said, noting that the Olympic qualifiers will run under 2:10. "I would really be going just to get the experience of racing in a big race like that."
His experience in the Baltimore race was "really cool" he said as Charm City residents in unlikely places lent their vocal support.
"Down around (Johns) Hopkins Hospital, where it seemed like every other house is boarded up, people were out on their porch or hanging out windows yelling, 'go teacher!' and 'go, Dave, go!' And the cheering when I crossed the finish line was insane."
Berdan said he was an average runner in high school who blossomed in college.
"I started out as the 12th runner on the team," he said. "Then I put in the work I needed to do to get better, running on weekends. By the end of the year, I had moved up to sixth."
After graduation, he moved near Asheville, N.C. to train until settling in Baltimore after meeting his future wife.
He taught science for two years at Booker T. Washington Middle School in West Baltimore before landing a job at Garrison Forest.
"I thought I was going to make a difference," (at the middle school, he said. "But after a while I just was burned out. I almost gave up teaching, but I'm glad I didn't. It's been a great experience here."
Senior cross country runner Gussie Smith also is happy that Berdan found a home at Garrison Forest, considering what he did for the team this fall.
She said that his approach to coaching was well received, and that he was "positive all the time and encourages us, but doesn't mess around. You can really tell that he knows what he is doing. He knows when we need to go harder or need to rest. Everyone's times were better this year and everyone was faster."