Every Sunday afternoon, around 2:30 pm, a line of "War Horse" performers snakes down the hallway just inside the stage door from the street. People are not vaguely annoyed, the way they might be at the supermarket when you choose the check-out with the customer who has to count out his or her payment in nickels and pennies while you quietly fume. The "War Horse" line is lively, and not only because people are happy to have made it to the final performance of the week. 

They are also cheerful because stage management has posted a physical-therapy sign-up sheet on the show's main backstage bulletin board, and they are there to put down their names for appointments. As I've said ad infinitum on this blog, "War Horse" is a physical show; so great are its demands on the body, that if I were to write a musical parody of the play the title would have to be "Sore Horse." 

Enter Jenni Green, physical therapist extraordinaire. PhysioArts, the company that she helped found a decade ago, provides much-needed services to the "War Horse" performers. Green and her colleagues -- Laura Becica as well as Michael Ballentine and Carol Holyoke - do not just give the actors a little massage where it hurts. They are integrally involved with the process by which the "War Horse" performers keep themselves together. 

"What's really unique about 'War Horse,' Green told me the other day, "is that Lincoln Center Theater and the show's creative team got me involved before rehearsals even started. We heard about the performers in the London production, and brainstormed how we could be of service in New York." 

Green says that for most shows with which PhysioArts is involved - a long list that includes "The Lion King" and "The Full Monty" - a main focus is on providing a preventive program. 

"With 'War Horse,'" Green explained, "we not only provide preventive care: soft-tissue work, joint work, taping. But we also get involved early on to do one-on-one screenings, especially for the puppeteers." After casting is completed, Green and her team evaluate performers for baseline strength, flexibility, balance, and posture, as well as assessing where people are at most risk for breakdown. 

"One good thing about the performers," Green explained, "is that they are on the whole very body- aware. They begin the rehearsal process in good physical shape." 

But Green said that even the fittest puppeteers have to learn to move efficiently with the weight of the horses on them. "With this show more than others, posture and body-mechanics training are crucial." 

"War Horse" performers, Green pointed out, experience what most actors do when they are onstage a lot. "They get over-use injuries. But where you are sore and tight can vary throughout the run." 

Backs and wrists are two especially big problem areas for the "War Horse" company. "The back gets stressed because people have to hold so much load," Green said. "The wrists are stressed because people have to maneuver with a lot of mechanisms that move the legs and head of the horses." 

"Backs are a very common area for actors to need work," Green pointed out. "But wrists are less common; they are not an area that most people strengthen." 

On whatever area the PhysioArts therapists focus, their work is essential to the day-to-day running of the production. The lucky performers may receive therapy once a week - with priority going to puppeteers and performers who have a specific, pressing need - but I suspect that the company would be willing to stand in line before every single show if it meant further sessions. 

"One of the great things about the 'War Horse' actors," Green said, "is how grateful they are for the services we provide." 

Brendan Lemon is the American theater critic for the Financial Times and the editor of lemonwade.com.