When he arrives shortly after dawn near the Hopkinton Common, a cool, misty air sweeps across the empty road. There are no water stations or spectators. The cheering section includes only his wife and two young children.
A week before the big race, and nearly a year after the most harrowing minutes of his life, Aaron Baggish and a fellow cardiologist who had been with him that day near the finish line set out to run their Boston Marathon.
The journey back to the city will require as much emotional stamina as physical, especially as the past blurs with the present.
No matter how much time has passed, the dark memories remain intense for the 38-year-old doctor from Cambridge, one of the race’s three medical directors and among the few first responders who has avoided speaking publicly about his experience.
Last April, Baggish had already been considered among the world’s leading experts on marathon-related deaths. But his experience overseeing a program for athletes at Massachusetts General Hospital had been confined to runners who had collapsed from heart issues, dehydration, or other ailments. None of that prepared him for what he experienced.
Now, hoping to reclaim the race for himself, Baggish is back on the starting line, reprising his annual tradition of running the route a week before the actual race.
After a kiss from his wife, Baggish and his friend start the long slog back to Boston, easing down the initial hill and moving swiftly toward Ashland. It’s overcast, with mild temperatures and a gentle breeze — ideal for running 26.2 miles.

It’s similar to the conditions a year before, when Baggish had time to putter around outside the medical tent on Marathon day. The cool, cloudy weather meant his staff was going to have it easy that day. He had little more to do than answer questions and walk the hundred yards or so to the finish line, where he kept watch for any problems with runners.
As Baggish and his friend pass into Framingham, the doctor thinks about some of the harder times he’s had on the route, which he’s run every year since 2002. He recalls how it was so hot in 2004 that he could see steam rise from the nearby train tracks. He also recalls the heat wave of 2012, when the temperatures soared to nearly 90 degrees on Marathon day, and he and his fellow volunteers worked nonstop to help care for a crush of patients.
“We thought we had seen Boston the worst it could get,” he says.
In Natick, Baggish meets his wife and children at a commuter rail station, where they’re waiting in a parking lot with water and big grins. They offer him high-fives, but his wife, Sylvia, who is six months pregnant, looks pensive.
“I then knew how connected she was with the complexity of this run for me,” he would say later.
When they pass through Natick Center, firefighters wave from their ladder engine as it rolls out of the station. Seeing them brings him back to the year before, when he stood in his blue and yellow windbreaker near the announcer’s booth, watching as the surge of charity runners trudged down Boylston Street. It was as peaceful a moment as ever at the Marathon, when all at once he felt the heat, saw the flash, and heard the massive blast — so close that he temporarily lost hearing in his right ear.
As they cross into Wellesley and near the halfway mark, Baggish picks up the pace, out of habit. The mile there is usually lined on Marathon day with screaming students from Wellesley College, but none of the usual kisses are on offer this morning. Baggish can run the course in under three hours, but he’s thinking more about the calendar than the clock.
On that terrible afternoon after the bombs exploded, Baggish was among the first to start ripping down the barricades. Through the smoke, he saw the glass shattered in the surrounding storefronts. He saw the blood all over the sidewalk. He saw the scattered body parts and heard the screaming.
More than anything, he recalls the overwhelming smell — the gunpowder and charred flesh, a stench he can’t forget.
On the long descent into Newton Lower Falls, Baggish’s legs still feel light and he skirts traffic to climb the hill over Route 128, perhaps the loneliest leg of the course. About a mile later, he and his friend turn onto Commonwealth Avenue by the Newton Fire Station and see the rows of daffodils that have been planted along the course to bloom for this year’s Marathon. A chilly rain begins to fall as he climbs the succession of slopes that culminate with Heartbreak Hill, where he finds his family waiting with more water.
As he hugs his 5-year-old daughter and 2-year-old son, he’s thankful they were too young to understand what happened last year, what he did, and the terror he has to live with.
Baggish recalls how, after the barricades were cleared, he began looking for those who needed his help the most. Immediately, he saw one woman suffering from catastrophic wounds. She was conscious and her eyes were open, but she was clearly taking her last breaths. He took off his belt and tied it around her pelvis. He did CPR as her pulse faded. He told her everything would be OK, even though he knew it wouldn’t be. He kept working to save Krystle Campbell until a firefighter relieved him, and then he moved on to help others.
On their way down to Boston College, with the Prudential Tower on Boylston Street now visible in the distance, the rain has become heavy, helping to blot the tears. His hamstrings tighten as he plods through the haunted mile and down to Cleveland Circle, only 4 miles from the finish line.
“I now realized in full that this run was my chance to get my Boston Marathon back,” he would say later.
As Baggish makes his way through Coolidge Corner in Brookline, over the Massachusetts Turnpike and toward Hereford Street, he feels twinges of anger — what he calls “seething reminders” — at how a race that means so much to him has been irrevocably changed, at how it left him rattled. He recalls the sleepless nights, breaking down in front of an audience while giving a routine talk, even losing his breakfast after a starting cannon caught him off guard at a later race.
He also recalls the screams, and how they guided him to who needed help urgently.
While officers shouted for everyone to stay alert to potential secondary devices, Baggish spent those long minutes using anything he could find to use as tourniquets, including a shoelace and the lanyard of a medal from the race. In all, he tied some eight tourniquets and only left when police escorted him back to the medical tent, his hands and clothes drenched in blood, his Marathon indelibly stained.
When he finally turns onto Boylston Street, Baggish speeds up to a near sprint. He’s now running alone, through traffic, strong and serene.
The barricades and the media bridge are back up and officers begin blocking traffic as they watch him approach, his resolve clear.
When the medical director finally crosses the finish line, the tears are heavy. He kneels on the faded yellow paint for a long moment, oblivious to the traffic, which officers direct around him.
Afterward, he slides through an opening in the barricades, and sits on the sidewalk in front of Marathon Sports, where he tried to save Krystle Campbell.
The memories flood into his mind even more now. He recalls how he never removed his sunglasses that day, because he was too afraid to make eye contact with the victims. He considers what has changed, and what hasn’t.
He feels good about his decision to return to the medical tent this Monday. There are thousands of additional runners and a lot of lingering anxieties.
His help will be needed more than ever.
“There’s no place that I’m more destined to be,” he says.
David Abel can be reached at dabel@globe.com. Follow him on Twitter @davabel.