BOSTON (AP) _ The Boston Marathon, which altered its start last year to give women their own send-off, will change it again in 2006 and release the rest of the field from Hopkinton in two, 10,000-runner waves.

The elite male competitors _ and about 9,900 other men and women who don't qualify for the elite field _ will begin the race at noon, the traditional starting time for the world's oldest annual marathon. The rest of the 20,000-runner field will start at 12:30 p.m.

The elite women will again start at 11:31 a.m., a change instituted last year to give their race more attention and a cleaner 42.2-kilometre path to the finish line in Boston's Back Bay. The wheelchair division starts at 11:25 a.m.

The two-wave start is designed to alleviate crowds in Hopkinton and allow organizers to manage the area better. While in past years runners might have waited 30 minutes to cross the starting line, it is expected to take each wave 10 minutes to cross the start this year.

The new start will also let runners warm-up more comfortably and away from the residential areas in the town. In the past, Hopkinton residents have complained about trash, and about competitors relieving themselves on lawns.

In unrelated moves, the last mile (1.6 kilometres) of the race will be altered so runners go in a tunnel under Massachusetts Avenue, instead of across it; organizers hope the change will tie up traffic less than in past years. The official time will also run 30 minutes longer, giving stragglers a chance to collect an official time until 6:30 p.m.

The 110th edition of the race will be run on April 17.