Where else but Martha’s Vineyard can a grandparent and grandchild compete against athletes and long-limbed teenagers without the competitive edge? Runners return every year for the Chilmark Road Race, and this weekend’s race is no exception. Everyone from Croc-wearing children to adults clad in high-tech sneakers will navigate the winding and hilly Middle Road on Saturday to compete in the 33rd annual Chilmark Road Race.

“We’re bursting at the seams,” race founder Hugh Weisman said earlier this week. Registration for the 1,500 runners closed last Saturday, and with a $20 registration fee for children 11 and younger and $30 for adults, the net proceeds of the race will benefit programs at the Chilmark Community Center. Last year, the race raised around $20,000.

“For many people it’s become a family affair,” Mr. Weisman said. “It’s a distance kids can run as well as grandparents.”

Mr. Weisman has been planning the road race since 1976, and what started out as a small, local race has grown into something so large that Chilmark officials required him to put a cap on the number of registrants. After 1,700 racers ran the course two years ago, the cap has remained firmly at 1,500. Planning for this year’s race began in May, but anticipation runs all year long.

“I get e-mails every winter asking me when the race is so people can book their vacations accordingly,” Mr. Weisman said. “It becomes part of everyone’s summer.”

One of his biggest concerns is the weather. With the record heat this year, Mr. Weisman has issued an advisory. “No one should run unless they’re healthy enough to do it,” he said. “We ask runners to attest to that.”

Tri-town ambulance and Chilmark police will be on the scene in case of emergency, but assuming all goes well, Mr. Weisman said he looks forward to everyone having a great time. With help from nearly 100 volunteers checking in runners and handing out water, for a few hours on Saturday Middle Road will be transformed from its usual bucolic state to a boisterous display of energy.

Mr. Weisman said he saw more competitive runners in the early years of the race than he has recently. Now, the road race is a family event.

“Running times have actually gotten a little slower,” he said. “There was a time in the 1980s when there may have been fewer marathons around and we had a lot of high-quality competitive runners. Now it’s become more of a recreational than competitive event, although there are still some fast runners.” Last year’s top winners included Anne Curi Preisig’s time of 18:56:0 for women, and Louis Serafini’s 16:21.0 for men. The race is five kilometers (3.1 miles).

Participants will be running not only to raise money for the community center but for the annual lobster: this year the winning prize weighs in at four or five pounds. Another coveted tradition are the T-shirts that runners receive at check-in. Mr. Weisman preferred to keep this year’s color theme a surprise.

The race starts east of the Chilmark town hall on Middle Road and finishes at Beetlebung Corner. Parking is limited and entrants are encouraged to either walk, bike or take the bus to the starting line. For those arriving from Woods Hole, a shuttle is being provided to and from the ferry.

While Mr. Weisman hasn’t run the race in a few years himself, his excitement remains unabated. “It’s great to see people come back year after year and of course it ages me when I see kids that were 13 or 14 running in the first race that are almost 50, it kind of puts the thing in perspective,” he said. “My kids ran it at that age and now they’re running with my teenage grandchildren.”

The 33rd annual Chilmark Road Race begins at 10:30 a.m. on Saturday on Middle Road. Participants are required to check in tonight or on Saturday morning. For more information visit chilmarkroadrace.org or call the Chilmark Community Center at 508-645-9484.