Jack Butler crosses the finish line of The Lucky Run half marathon on March 7 in Davis, Calif. Photo: Melissa Butler
Jack Butler crosses the finish line of The Lucky Run half marathon on March 7 in Davis, Calif. Photo: Melissa Butler

In just his second half marathon, Jack Butler became a world record-holder. The 10-year-old from Sacramento, Calif., ran a 1:31:08 on March 7 at The Lucky Run in Davis, Calif., finishing 16th overall and averaging 6:57 per mile. In January, he ran a 1:35:26 at the Rock ‘n’ Roll Arizona 1/2 Marathon, placing seventh in the 14-and-under age group and 353rd overall.

Butler, who is in the fifth grade, has been running for a few years in a youth running club organized by his mother, Melissa Butler, a 2015 Boston Marathon qualifier and veteran of 10 marathons. Jack used to help his mom with her speed work by pacing alongside of her on his bike. As of late, he’s been running with his mom’s Boston Marathon training group, often outrunning some of the club’s veteran adult runners. He’ll be in Boston in April, not only to cheer on his mom and their training partner, Cynthia Ortiz, but also to run in the B.A.A. 5K.

“We train some together. It started out as 5Ks about three years ago and then he tried 10Ks,” says Melissa Butler, who qualified for Boston with a 3:29 marathon at the California International Marathon in 2013. “He quickly started getting too fast for me, but we still run mostly together or I will bike at his pace with him. He usually places in his age group with 14- and 15-year-olds in all his races.”

She says her son runs about 12-20 miles per week, but she also says that she’s not pushing him into it. He loves to run, she says, and she’s trying to help him do it in the most healthy way possible.

“I realize some people will say it’s unhealthy for him, I’ve never had that concern,” she says. “If he’s tired he stops, if he’s feeling ‘off’ that day we cut it short. He’ll take 3-4 days off sometimes and other weeks he feels great and runs a little more. He keeps track of his shoe mileage and doesn’t wear them past 350 miles. I tried to do at least a portion of his long runs on softer surfaces.”

Also on March 7, Megan Crum set a new 5K world record for 7-year-old girls with an 18:25 clocking at the Run with a PAAL race in South El Monte, Calif. She finished 14th overall and first among female runners in that race, averaging 5:55 per mile. Crum also holds the world 5K mark for 6-year-olds with her 22:18 effort from last July at a race in San Diego.

Those stellar times from Butler and Crum are part of a growing trend. They’re the latest American youngsters to set world records in road running events from 5K to the half marathon over the past two years.

Earlier this year, Dallas Stricker set an 8-year-old world record in the half marathon by running a 1:43:08 in Waveland, Fla. Last year, Stricker set a 7-year-old mark (1:43:53), while Hunter Perez (11, 1:24:10), William Stone (9, 1:41:07) and Cael Schwartz (6, 2:19:48) also set world marks for that distance. New girls half marathon world records have been set by Americans Heather Welsch (11, 1:32:23), Makenzie Kolvoord (7, 1:40:59) and Rosie Dunham (6, 2:40:22) in the past two years.

In January, Reagan Jones set a new 10K world record for 8-year-old girls with a 45:31 effort in Ocean Springs, Miss., In November, Grattan O’Neill set a new 10K world record for 7-year-old boys with a 42:40.1 effort in Florence, Ala. Kolvoord also set a new 7-year-old 10K world record last fall with a 46:07 clocking. O’Neill also set a 7-year-old world record for 10 miles, running 1:15:23 in January at a race in Homewood, Ala.

On top of that, nine 5K world records for the single-age categories of 4 to 12 have been set by American boys since 2013—among the most notable marks are James Reed’s 24:08 for 5-year-olds set last October in Duluth, Ga., and Zach Blum’s 9-year-old mark of 18:30.9 set last November in Tustin, Calif.