Boyscouts from Troop 1367 participate in a flag retirement ceremony in Woodbridge, VA, June 14, 2011. Linda Davidson/The Washington Post/Getty Images

Extremely overweight Boy Scouts are banned this year from the scouts' annual Jamboree, which is expected to be the most physically-demanding in the organization's history.

The Boy Scouts of America organization said they published their height/weight requirements for this year's national gathering years in advance so scouts would have a reason to work toward healthy goals.

"Teaching scouts and scouters how to live a sustainable life, which includes a healthy lifestyle, and the health of our participants are important goals of the jamboree. We published our height weight requirements years in advance and many individuals began a health regimen to lose weight and attend the jamboree. But, for those who couldn't, most self-selected and chose not to apply," Deron Smith, spokesman for the BSA, said in a statement to ABC News.

The jamboree, which attracts thousands of scouts from across the country for 10 days of hiking, camping, and other activities, will take place for the first time this year at the Summit Bechtel Family National Scout Reserve in West Virginia.

Organizers told the Associated Press that the new location was specifically designed to promote physical fitness among scouts by forcing them to walk far distances over hilly terrain or hike mountains to attend various activities.

"Additionally, as the newest high adventure base of the BSA, The Summit is a fun but physically demanding facility with numerous high-adventure activities, including kayaking, rock climbing, bouldering, skateboarding, BMX, and various other activities," Smith's statement to ABC News said.

Scouts with a body mass index of 40 or higher were not eligible to attend the gathering, the AP reported. The average weight for a 12-year-old boy is 90 pounds. An obese 12 year old is more than 130 pounds, according to the Centers for Disease Control and Prevention.

The BSA said they it did not know how many scouts were affected.