BOSTON (AP) – The Boston Marathon is breaking with a century-old tradition and moving up its start time by two hours.

The change was announced Monday by the Boston Athletic Association, the race organizer, in an attempt to ease traffic in the eight cities and towns along the course and give runners a break from warmer temperatures later in the day.

Organizers of the world’s oldest annual marathon had been discussing the idea of starting at 10 a.m. instead of noon with city and town officials since last year, when the marathon introduced a two-wave start. That enabled the 10,000 fastest runners to start at the scheduled time and the balance of the field to start a half-hour later.

Breaking up the start gives organizers more time to bus the 22,500 registered runners from Boston to the start in Hopkinton.

“The positives for the runners and for the communities and the feedback from the medical community seem to all be on the side of the ledger saying this was a really good idea,” said Jack Fleming, spokesman for the Boston Athletic Association.

The Boston Marathon follows a 26.2-mile route from Hopkinton into Ashland, then Framingham, Natick, Wellesley, Newton, Brookline and, finally, Boston. The inaugural race, held in 1897, began at 12:19 p.m. It traditionally got under way at noon in the 109 races that followed.

The association said it changed the start time after receiving approval from officials in each community along the route, as well as from the state.

The mobility-impaired program, wheelchair and elite women’s divisions will continue to start earlier.

“It’s great,” said Bill Rodgers, 58, a four-time winner of the Boston Marathon. “Because it’s an endurance sport, the cooler the conditions the better for all the athletes.

“If they could push it up another two that would be even better,” he said.

Rodgers said moving up the start will make Boston a stronger race, just as adding prize in 1986 did. He also said it would give runners a better chance at setting records.

“You cannot get records in warm weather conditions,” said Rodgers, who dropped out of Boston mid-race three times – all three in high temperatures.

The association cited several reasons, in addition to weather and traffic concerns, for making the change: Runners overwhelmingly prefer the earlier start; the event’s medical directors support the move; and international media deadlines would be more easily met, allowing for better coverage.

The new start time marks a change in a day of traditions in Massachusetts, and could provoke another: On the day of the marathon, the Red Sox have long had an 11 a.m. game at Fenway Park, which is located just blocks from the finish line. Baseball fans have traditionally been able to catch the finish of the race right after the game.

The 2007 race will be on Monday, April 16.

Fleming said part of the reason for announcing the change early was to give the Red Sox time to consider a schedule change. Red Sox spokesman John Blake said no decision had been made yet.

Hopkinton Police Chief Thomas Irvin said the new time is good news for his town from a logistical and public safety standpoint, though some people may need to get up for work a bit earlier. He said he didn’t expect much resistance to breaking with tradition.

“The race has enough of a reputation that it can weather this change without really harming the tradition of the overall event,” Irvin said.

AP-ES-08-21-06 1806EDT