Liz Lerman’s Martha Wittman and the University of Maryland Symphony’s Enrico Lopez-Yanez during rehearsal. (Nguyen Nguyen/Nguyen Nguyen)

A concert pianist takes the stage: dressed all in black, walking out into the circle of golden light, slightly hunched forward under the applause, scuttling with single-minded purpose toward the waiting, looming concert grand.

This is not part of the performance. We, the audience, are here to experience music, to hear the sounds his fingers make when he touches the keys, to hear the way he brings a composer’s music to life. And yet we’re looking, too, because we have come to this hall to experience live music, which involves bringing all of one’s senses to bear — doesn’t it? Otherwise, we might as well listen through speakers at home.

What part does movement have in musical performance? Musicians seem uncertain — or unaware. On the one hand, it’s a new truism that classical music concerts “need” a visual element to captivate new audiences (“Classical music must, in order to survive, introduce visual elements into its presentation,” wrote Patricia Handy in her program notes for Augustin Hadelich’s ostensibly theatrical “Tango, Song and Dance” program at the Terrace Theater last week).

On the other hand, classical musicians, and their audiences, don’t tend to be aware about the abundant visual elements they’ve already got. Yes, piano aficionados attending recitals ask for tickets on the left side of the auditorium so they can see the player’s hands; yes, in television broadcasts of orchestra performances, the cameras zoom in on individual players so viewers can watch the flutist’s fingers, the oboe player’s puffed cheeks, as they play their solo lines. But let a musician be deliberate about making theatrical movements while he plays, and purists will heap scorn upon him. Just ask the pianist Lang Lang.

This often leads to a sense of randomness in performance. Hadelich’s “Tango” program was a case in point. At a couple of points the pianist Joyce Yang, one of the other two musicians involved, got up and walked around the stage without conveying any sense of why she was doing so. At another moment she played, hunched over the keyboard, focused on expressivity rather than the awkward curve of her spine. One set of movements was deliberate, and one unconscious. In neither case did she claim them, lend them authority, make them her own.

This week, two different local orchestras are bringing movement to their performances — in different ways. On Thursday, the National Symphony Orchestra is starting a three-part, all-American festival called “New Moves” (Wednesday to 18): three concert programs that each include a concerto, a concert work, and a work of dance. Three different choreographers — Larry Keigwin, Jessica Lang and the dancers of Memphis’s New Ballet Ensemble — have created works to be danced, by their own dancers, onstage with the orchestra.

The University of Maryland Symphony Orchestra’s concert Sunday goes a step further in integrating movement. The choreographer Liz Lerman, who worked with the students to create the remarkable “Prelude to the Afternoon of a Faun” two years ago, is returning for an “Appalachian Spring” on the same model. The musicians have memorized their parts and move around the stage as they play: a challenging feat that shakes up concert tradition. “Part of what’s so wonderful about it,” Lerman said last week, “is how it messes up how they’re hearing each other just by putting people in different proximity.” It’s also a rare fusion of two art forms in which the same performers are taking responsibility for both music and visuals themselves.

If this fusion is rare, it’s not choreographers’ fault. That dance is often presented in orchestra performances as an appendage to music is a function of the available rehearsal time. Lang, who is choreographing John Adams’s violin concert for the final “New Moves” concert (May 16 and 17), is trying to link the dance to the instrumentalists as much as possible, starting by placing dancers throughout the orchestra during the first movement. “I didn’t want the dancers to not be a part of the orchestra,” she said. But she can’t actually work with the musicians much; the dance is being created in her New York studio. “We come to the Kennedy Center, get introduced to the soloist and orchestra and Wednesday, and premiere on Friday,” Lang said.

So the dance, in this standard approach, is a separate entity: something that can be added to the performance but is not necessarily an integral part of it. Indeed, Lang plans to take it into her company’s repertory and perform it without orchestra once the NSO concerts are finished. She certainly can’t work with the violin soloist, Leila Josefowicz, the way that Tricia Brown worked with the baritone Simon Keenlyside, who literally danced his way through their 2002 collaboration on Schubert’s song cycle “Winterreise.” “We do have some gestural work that possibly, potentially could make you see her movement more clearly,” Lang says, adding, “I don’t know if she’s a big swayer; I will assume she is.”

Some orchestras, certainly, are dabbling with involving musicians in different ways in performance. In 2013, the New York Philharmonic took up a version of the “Petrushka” that the artist and director Doug Fitch originally created for the University of Maryland orchestra, in which some of the musicians wore costumes (hats, slippers) and performed various pieces of stage business (drinking tea). But few professional orchestras are willing or able to devote the kind of time it takes to present the kind of fully integrated performance the University of Maryland will present, in which it’s a challenge to separate dance from music. “Innovation requires time,” Lerman says. “I don’t know that the [players] would love memorizing.” (For the record, the Maryland students committed the 23-minute piece to heart eagerly, and have been coming up with all kinds of suggestions on their own; one cellist even developed a harness for her instrument that allows the cello section to move around more freely than they are usually able.)

Integrating movement into classical performance is at once an uphill battle and a step toward opening a dormant and powerful channel of communication. Classical concerts are notorious for having become places of artificial silence and stillness, on and off the stage: Silent audience members glare at those who rustle their candy wrappers or clap in the wrong places.

“Maybe we went too far with the whole don’t applaud between movements, don’t participate, don’t be a human being,” says Thomas Wilkins, who will conduct the three NSO programs. “To the point that it gave some people outside of classical music the wrong impression of what classical music was.”

And people inside of classical music, as well. Some purists find it distracting that the musicians of the Berlin Philharmonic energetically move while they play, or write me to complain about the Baltimore Symphony Orchestra’s concertmaster, Jonathan Carney, who is certainly one of the most physical violinists on the stage.

What we’re left with is an assortment of what one might call “junk movement,” a faux-physicality, on the part of many performers, that could become so much more effective if it were addressed, and harnessed. In an early rehearsal for “Faun,” Lerman said, “I tried to get people to notice what they did naturally and see that that’s a thing; it can even be a design thing, particularly if they were willing to share it with each other. ‘How about if we all move like Josh when he plays?’ It’s a very subtle kind of learning.”

“As much as this is about movement,” she continues, “because they move so much anyway, it’s also about not moving.” If this line of artistic inquiry were to be more widely pursued — and Lerman is eager to see whether any of these young instrumentalists she’s working with continue to develop it — “one of the skills musicians would need to learn,” she says, “is to be still.”

Appalachian Spring will be performed Sunday at 4 p.m. at the Clarice Smith Center at the University of Maryland. 301-405-2787. www.claricesmithcenter.

The NSO’s “New Moves” festival begins on Thursday at 7 pm and continues through May 18 at the Kennedy Center Concert Hall. 202-467-4600.