Conner Mantz, the 2024 U.S. Olympic marathoner and American marathon record holder, posted his first structured workout on Strava this week after months sidelined with an injury.
The session — 3x(mile, 800m) with tempo miles in 4:36, 4:36, and 4:35 and 800s in 2:08, 2:05, and 2:03 — was solid by any measure. But with the Boston Marathon just nine and a half weeks away on April 20, the question on everyone’s mind is whether the 26-year-old can get anywhere close to race shape in time.
Mantz titled the Strava post “Baby deer,” a nod to the wobbly-legged feeling of returning to fast running after a long break. “I tried to stay with Casey as long as possible each rep,” he wrote, referring to training partner Casey Clinger. “My legs are not used to running this fast.”
When asked in the Strava comments whether he planned to run Boston, Mantz was cautiously optimistic: “As long as another injury doesn’t come up.”
A Rapid Return to Training
The comeback timeline has raised eyebrows in the running community. According to his public Strava data, Mantz was doing half-mile walk-jog sessions as recently as January 2, and by mid-February he was already logging roughly 45 miles in four days and running tempo efforts at altitude in Provo, Utah.
Some observers on the LetsRun message boards — the sport’s unofficial town square — flagged the mileage ramp as aggressive. Others pushed back, noting that bone stress injuries tend to have a more straightforward recovery timeline compared to soft tissue damage, and that a runner with Mantz’s years of high-volume training can safely rebuild faster than most.
“If the injury is healed, and given the amount of time he stayed off his feet, it should be, then there’s no issue with ramping up fairly quickly,” one forum commenter wrote. “He’s been running big miles for years.”
There’s also the possibility that not everything is on Strava. As one poster noted, “You do realize this is merely what he posted publicly and chose to share. He could have had previous runs or workouts for weeks that he either didn’t post or simply set to private.”
Even if Mantz’s body holds up, the bigger challenge may be the simple math of marathon preparation. Elite marathoners typically build over 12 to 16 weeks of heavy, specific training to peak for a race — long runs at goal pace, high mileage weeks well over 100 miles, tune-up races. Mantz has roughly half that runway.
The marathon rewards accumulated training load more than perhaps any other event. While Mantz’s deep aerobic base from years of 100-plus mile weeks hasn’t disappeared, the specific fitness required to race 26.2 miles at sub-5:00 pace takes time to sharpen.
Who Is Conner Mantz?
For those less familiar, Mantz is a former BYU standout who made the 2024 U.S. Olympic Marathon Team after a breakout performance at the Olympic Trials in Orlando. He and training partner Clayton Young, who also trains under coach Ed Eyestone in Utah, have emerged as two of the most promising American marathoners of their generation.
Mantz first turned heads with a 2:08:16 debut marathon at the 2022 Chicago Marathon, which at the time was one of the fastest American debuts ever. He represented the United States at the 2024 Paris Olympics and has established himself as a fixture on the American road racing scene.
His appearance on the Boston start line would add a compelling storyline to the 2026 race: a talented but under-prepared American trying to compete against a deep international field while still finding his legs after injury.
What to Watch For
With nine weeks still to go, a lot can change. If Mantz can string together several weeks of healthy, progressive training — building his long runs and adding more race-specific work — he could surprise people in Boston. The enforced rest may even work in his favor to some degree, giving his body a chance to absorb years of hard training while coming into the race fresher than usual.
But the margin for error is razor thin. One setback, one tweak, and the whole plan falls apart. As one observer put it: “I think no one, Mantz and Young included, would deny that it’s a really quick turnaround and that the odds are really long. But they’re going to give it a shot and that’s respectable.”
For now, the baby deer is up and running again. Boston will tell us the rest.
