"I Don't Feel Old When I'm Dancing," a Channel 5 special about senior citizens involved in dance performances, manages to be both touching and enlightening despite its fractured form and treacly atmosphere.

The half-hour program, which airs at 8:30 tonight, is essentially a documentary about the Dancers of the Third Age, an integrated group founded by Washington dancer-choreographer Liz Lerman some years ago, which she has shepherded through extensive theatrical and community performances since. A favorably reviewed book by Lerman -- a pioneer in this field -- on teaching dance to senior adults was published earlier this year. The troupe's assistant director, Don Zuckerman, is the on-screen leader for the TV show.

Both the Third Age ensemble and the program are reflections of Lerman's philosophy -- in a nutshell, that dance performance (not just social dancing) should not be the exclusive domain of a youthful professional elite. Her own work with the Dance Exchange Performance Company has often used casts mixing children, adult professionals and seniors, with interesting and surprising results.

On one level, the activity has socio-therapeutic aspects -- it forms, as Lerman puts it, "a bridge between people" of all generations and backgrounds. One sees and hears affecting evidence of this on screen when Thelma, 87, raised on an Iowa farm, tells us that "it turned my life around completely . . . I feel like I'm floating through air"; or when Charlie, 64, a retired Methodist minister, says, "It gets my juices flowing"; or when Jess, 61, a modern dancer in earlier years, explains, "When the body moves, the spirit moves." Another sort of evidence is contained in the lighted faces and animated bodies as they move.

On another level, the dancing produces various kinds of esthetic fallout, starting with the unique line, amplitude and feeling that only an older performer can generate. The Third Age dancers bring a lot of personal history to every movement; what the viewer focuses on isn't technique, but honesty of expression.

The program also demonstrates how everyday experience from the lives of the group becomes the raw material for dance motifs -- a visit to a video arcade gets one bunch into a giddy body English; Charlie's reminiscences about swimming and the breast stroke initiate a row of arching arms; Vee's girlhood in Adirondack lumber territory (she's 85 and the self-described "rascal" of the troupe) stimulates an episode of chopping motions and a square dance. A finale on the theme of a rainbow and the pot of gold is followed by brief profiles of the dancers, ending with a smiling Thelma exclaiming, "I don't feel old when I'm dancing."

The program is a disjointed blur of cuts, close-ups, dissolves and freezes -- images are seldom permitted as much as a second on screen. Any gain in pace and fluidity -- the presumable motive for the hyperactive style -- is offset by the fragmenting of both the dance movement and the story, which the viewer must painfully piece together from jumbled hints. However, this is one instance in which the material triumphs over the mannerism of its treatment -- the Dancers of the Third Age make an irresistible case for themselves.