The American Alliance for Health, Physical Education, Recreation and Dance’s 127^th annual meeting was meant to kick off March 13-17 at the Hynes Convention Center in Boston, but most of the event now has been canceled after a nearby electrical transformer fire knocked out power to the building on the event’s opening day.

The power outage not only impacted the meeting in the city’s Back Bay neighborhood, but also more than 20,000 residences and several surrounding businesses, including the Hilton, Westin and Sheraton hotels.

When the power was still out the morning of March 15, the Massachusetts Convention Center Authority, which oversees the Hynes, and AAHPERD meeting representatives announced most aspects of the event, which had an expected 6,000 attendees and exhibit space at the Hynes, would be canceled because of health and safety issues.

“We had to make the decision this morning to cancel the show,” said Paula Kun, AAHPERD’s senior director of communications.

She said the association was in constant contact with city, hotel and convention center representatives, and after it was determined there was no guarantee of power on March 15 until maybe later in the day, most events were scrapped.

The exhibit hall, which typically draws 300 exhibitors and was scheduled to open at noon March 14, was completely canceled as well.

“Everyone was very disappointed, of course,” Kun said. “We are the only major physical education event in the country, so a lot of people were really looking forward to it.”

She added, “It’s no one’s fault though. What can you do?”

There were 4,400 preregistrations, Kun said, and they expected another 1,600, mainly local teachers, to register onsite for the five-day event.

James E. Rooney, executive director of the MCCA, said the substation where the transformer caught on fire was very close to the West side of the Hynes.

“At first, people didn’t know what was happening because there was a lot of smoke in the air,” he added. Rooney said as more time passed, and it became apparent power would not be up by the following day, there was a meeting with AAHPERD officials.

“It was an easy decision to make to cancel the event that day knowing there would be no power,” he added.

The utility company, though, indicated power would be restored later that same day, so there were plans to open the show on March 15.

“Over the course of last night, it became clear that power could not be restored,” Rooney said. As a result, he added, the decision was made to cancel all aspects of the event that were scheduled for the center.

Kun said members of the five associations who attend the event – the American Association for Health Education, the American Association for Physical Activity and Recreation,  the National Association for Girls and Women in Sport, the National Association for Sport and Physical Educationand the National Dance Association– tend to be easygoing people so they were understanding of the overall situation.

In fact, AAHPERD representatives still decided to go ahead with the March 15 general session at a nearby Sheraton ballroom, even though the hotel was still on generator power.

“It was standing-room only with 700 to 800 people,” Kun said.

She added that they also still planned to have their Hall of Fame dinner March 16, which honors individuals in the profession. “We hope people don’t start leaving town,” Kun said.

Rooney said that everyone understood the decision to cancel the event.

“We certainly wish … the people that came to Boston could have had the event they were meant to have,” he added. “But they certainly will leave with some stories.”

Rooney said it was hard to communicate the severity of what happened.

“These are huge transformers,” he added. “One had the fire and damaged the other one. It was a very serious incident.”

For now, Rooney said, power is expected to come back some time in the evening March 15.

AAHPERD’s annual meeting is scheduled to head to Charlotte, N.C. next year and is on the books again in 2017 in Boston, according to Kun.