Tim Geraghty is among that elite group of runners—an estimated 10 percent—fast enough to qualify for the Boston Marathon.

Runners had to race 2 minutes and 28 seconds faster than the usual qualifying time for their age group and gender to qualify for this year’s Marathon, which for 22-year-old Geraghty (ENG’16) meant 3 hours and 5 minutes.

He beat that qualifying time by 10 minutes by running the 2014 Chicago Marathon at a personal best of 2:55. He is aiming to surpass that record when he joins an estimated 26,000 runners at Monday’s 120th Boston Marathon.

“I’m really looking forward to being out there,” says the Illinois native, who has run the Chicago Marathon three times, the first in 2013. “I’ve been studying Boston’s topography, and the first 4 miles or so are downhill, and then you have Heartbreak Hill at mile 21, so it’s important to hold back a little bit, save your energy for later. I plan to feed off the crowd’s energy.”

One hurdle that might affect that time is the weather—Monday’s forecast is a high of about 72 degrees and sunny, unfavorable conditions for runners. Hydration, early and often, will be key.

A runner since the sixth grade, Geraghty says a friend tricked him into hitting the pavement, saying that long distance running was like competing in an obstacle course. He ran cross-country in high school and set a goal—to be able eventually to complete a marathon. Coming to BU to study engineering, Geraghty was already pressed for time, so opted to run on his own instead of joining the track and field team. Running Boston has been in his sights ever since he applied to BU.

Looking to improve on his time, training, and approach, he signed up for this semester’s FitRec’s marathon training class, led by veteran marathoner Jennifer Carter-Battaglino (SED’03). “Since she has run Boston, she is very knowledgeable about strategy, diet, and hydration tips,” says Geraghty, whose diet for the last few weeks has consisted mostly of carbs and proteins, like chicken, lean meats, pasta, and whole grain bread.

“The fact that he qualified for Boston is super-impressive,” Carter-Battaglino says. “I think he’ll do well, and he’s been doing a great job in training.” Geraghty embarked on a regimen of speed workouts, tempo runs, Yasso 800s, track workouts, and hill repeats, which, in theory, should prepare a runner for the grueling Heartbreak Hill. “In class, most of us would do a hill repeat one or two times, but Tim would do it three or four,” Carter-Battaglino says.

Geraghty’s conditioning involved something more. The mechanical engineering major is also a StuViII resident assistant (in addition to being a student government judicial commissioner and a member of the Catholic Student Association), and on nights when he was on duty and couldn’t leave the building, he got in his workout by running up and down StuViII’s 26 flights of stairs.

Come Marathon morning, Geraghty says, he expects he’ll be a little nervous, but plans to treat the race as “just another long run. Runs tend to max out at 20 miles, so the last 6 on Monday will be about mental toughness and adrenaline.” His parents will be tracking his progress online from Chicago and cousins and friends will be spread along the 26.2 mile route cheering him on. “A lot of people ask me what I like the best about running,” he says. “I like being outside, being with my thoughts, exploring, and pushing myself to be better.”

When he crosses the finish line Monday, Geraghty has no plans to slow down. Next up is November’s New York City Marathon, and after that, an even more ambitious goal: he plans to run marathons in all 50 states and on all 7 continents, even Antarctica.

The 120th Boston Marathon is Monday, April 18, beginning at 9 a.m., in Hopkinton, Mass. The prime viewing location is along Beacon Street, from East Campus through Brookline. The first runners should hit that area sometime after 11:30 a.m. Check out this online map to track how the marathon will progress.