Participants in a 4-mile race planned for Sunday in Central Park picked up tee-shirts  at the New York Road Runners headquarters that read: "I run for... Boston."

Approximately 7,000 runners are expected to participate in the City Parks Foundation Run for the Parks. It will be one of the first major races to be held in New York City since the Boston Marathon bombings earlier this week.

Runners said that they wanted to show solidarity with the victims in Boston.

"It's really just to support the families and people who were injured," said race participant David Kim. "It's a small gesture we can do that's visual, that's symbolic."

Runners are being encouraged not to bring bags but people who do will be asked to put all their belongings in a clear, plastic bag provided by race officials. The NYRR cautions runners that any unattended bags will be confiscated.

Runners in shorter-distance events have traditionally been allowed to use their own bags to stash their clothes and other post-race items, which are stored in a designated area staffed by volunteers. But many longer, larger races tightened their gear-check policies several years ago, requiring all runners to use a bag — often clear — provided by organizers. Organizers of the half-marathon and marathon in Austin, Texas, for example, have been providing runners with clear plastic bags for their belongings for almost a decade.

At Sunday's London Marathon, only gear stored in the official bag provided by race organizers will be accepted. Next weekend's Oklahoma City Memorial Marathon and Half-Marathon, organized as a tribute to the victims of the 1995 bombing that killed 168 people at that city's federal building, only accepts gear in the clear plastic bag it provides runners.

New York Road Runners puts on dozens of races a year, including the New York City Marathon. The club did not say if the policy for Sunday's run will extend to future races.

The NYPD is planning to remove all trash cans from the race course Sunday. Runners should also expect fewer available bathrooms.

"I trust the city and I think the police will be there in full force," said race participant Lindsay Flora. "We're runners, we'll get through it."