Cowbells rang, Matracas rattled and Elvia Negron-Perez, who has completed 12 New York City Marathons, offered runners in Sunday’s race relief at her folding table along 135th Street in the Bronx.

Dressed as “Super Boricua,” Negron-Perez stood a few feet north of the Mile 20 marker wearing a Puerto Rican flag draped over her shoulders and wristbands emblazoned with its image. In plastic bags, she assembled care packages of bananas, oranges and pretzels for friends on the course. She reached into a container to pull out a muscle-roller massage stick, and tried to ensure that anyone thinking of surrendering to physical pain or mental exhaustion did not do it on her block.

“No wall!” she said. “We’re here for everybody!”

While the marathon’s annual visit to the Bronx is brief — just over a mile — it has often brought out the best in the borough. The Mott Haven neighborhood in particular has become synonymous with moral support and muscle sticks on race day. Positioned at the foot of the Willis Avenue Bridge, where runners and wheelchair racers cross into their fifth borough of the route, residents come to the course equipped to assist those whose bodies may be breaking down.

Neil Heckman, who ran in 2014 and 2015, said he never forgot cramping the first time he reached Mile 20. On the sideline on Sunday, he wore a black headband, offered bagged snacks and kept a roller at the ready. As morning burned into afternoon, he held up a white sign to alert the participants that he had relief available for the asking.