If you're overweight and want to see a production at St. Paul's Circus Juventas, consider yourself warned.

Under the heading "Patrons of Size" on its website, the youth circus is now urging the overweight to "proactively book the number of seats needed" before the performance or risk being moved to a different location when the show is starting.

The circus says the seats, installed in March, are 18-inch molded plastic seats with no separation between them, meaning that a heavy person could spill over into the space next to them.

"We want to advise people that if they do need special seating to plan in advance, because Circus Juventas usually sells out and it's very uncomfortable for a larger person to be unable to find a seat that works without crowding others," said Connie Shaver, who does publicity for the circus. "It's being proactive."

The circus appears to be among the first to publicly request such measures. Other venues have increased seat widths to keep pace with a growing population.

A study released Monday by the national Theatre Projects Consultants said chair width and legroom have expanded to accommodate the larger size of American theatergoers. The standard seat width was increased from 19 inches in 1900 to 20 in 1990. Since 1990, it has expanded to 21 to 22 inches.

The Guthrie Theater is keeping pace. The seats at the old Guthrie at Vineland Place ranged from 18 to 21 inches. At the new theater, seats at the Proscenium Stage are 20 to 22 inches wide; in the Thrust Stage, a few are 19 inches wide, but they range up to 23.

Officials at Target Center, Ordway and other venues in the Twin Cities said they often accommodate overweight patrons, just as they do taller or shorter patrons or those who are hard of hearing. Most said they place heavy patrons on detached seats in the handicapped area, if space allows.

"Really, the goal is to make everyone comfortable and avoid a last-minute situation where you're trying to seat someone," said Shaver. "If it can be addressed in advance, it won't be a problem."

At the brand-new Target Field, heavier patrons are put in one of the 794 handicapped spots, if there is room there, said team spokesman Kevin Smith. Overweight fans also have the option to go to the standing-room-only areas, he said. A more complicated issue, he said, is when a smaller person feels his or her space is compromised by an overweight person in the next seat. In the Metrodome, it was easy to move a fan to a different seat because so many were available. But games at Target Field are sold out.

When that happens, there's not much the team can do, he said. "You have to work with the person next to you to try to figure out a way you can both coexist for three hours," he said.

Suzanne Ziegler • 612-673-1707