You should pray for a sound mind in a sound body.

Juvenal (A.D. 60?-140?)

A lot of people are caught up in the current of physical-fitness consciousness. From "shape-up" clothes to "cool-down" stretches, producing and maintaining a sound body is a priority for millions of Americans. But perhaps it is time to heed the words of the Roman poet Juvenal and commit ourselves to exercising our minds as well as our bodies.

A regular program of reading and discussing intellectually challenging books need not be limited to the hallowed halls of academia. Rather, a book-discussion group is an effective and enjoyable way of becoming more mentally fit.

Any reader can form a book group with friends or join one sponsored by various public libraries or church groups in the area. The tone of the meetings can range from a low-key, unstructured atmosphere to a more formal discussion in which outside source information (biographies, reviews and criticisms) is used and guest speakers are heard.

One major benefit of an organized book group is that it helps initiate and sustain quality reading. The inability to find time for reading is a universal problem. Personal reading is easily put off. "As soon as I finish this project at work . . . " or "When the baby's schedule is more regular . . . " are familiar excuses.

The deadline of an upcoming meeting forces one to overcome such evasive habits and find time to read.

Beverly Bryce, librarian at Holy Names Academy, Silver Spring, formed a book group 12 years ago because, she says, "With three children under the age of 3, I needed a push to keep reading."

Her group, which now includes eight working mothers, prides itself on the high intellectual level of its book selections and discussions. Exchanges of recipes and talk of their children do not slip into the evening's topics. "The intellectual comraderie is what means the most to me," says Bryce, 46.

Former English teacher Christine McGovern, 35, and the mother of three young children, feels at-home mothers like herself "need a separate time, without the children, to share ideas with other adults." The Bethesda resident says her 2-year-old book group provides the intellectual interaction once provided by teaching.

Similarly, Patricia Brandson of Bethesda, another former English teacher and a mother of three, finds that being at home provides "little immediate intellectual satisfaction." Brandson, 35, says participation in a book group gives her a "sense of outside discipline" that she appreciates.

As our educational system and career fields become more and more specialized, a book group can help expand reading experiences.

New Jersey resident Becky Trenta, a 33-year-old former government policy analyst and Arlingtonian, needed a break from her professional duties of reading formal, monotonous government documents, so she formed a book group with three other women. "The political focus in Washington can be all-consuming," she says. "I wanted to improve my intellectual life with something more balanced. I needed a more formal approach to my personal reading."

Meeting monthly over dinner in a member's home, the group selected works by such literary greats as Shakespeare, Tolstoy, Chekhov and Thomas Mann, as well as more contemporary writers like William Styron, Flannery O'Connor and John Irving.

"I often said that I'd like to read a particular book sometime," says 39-year-old Jim Hastings, an archivist with the National Archives. Following a friend's suggestion, he "reluctantly" joined an established book group of eight men in varied professions (including lawyers, a doctor and a Navy officer).

Although always a casual reader, "I was never inclined toward discussing books," says Hastings, "never big on class participation." Now enthusiastic about the experience and comfortable about sharing his ideas, he says that he is talking more than he ever expected and discussing books he might never have read. Two examples he cites: Gail Godwin's A Mother and Two Daughters and Anne Tyler's Dinner at the Homesick Restaurant.

A formal book group also furnishes ideas for reading that go beyond the best-seller lists and may be more stimulating. Although names like Eudora Welty and Peter Taylor are not as familiar as Judith Krantz or Sidney Sheldon, the rewards in reading them can be greater.

Members of books groups usually find themselves scouring book review sections for suitable selections. In some groups, members suggest and mutually agree on books to be discussed; in others, each member is responsible periodically for the choice.

Beverly Bryce says her group makes a deliberate attempt to read varied works: the classics as well as contemporary books, nonfiction and fiction, by black and white authors, foreign and American writers. "We always," she says, "try to take the high road. We like to read things that might take a little more out of us."

The group used the Dartmouth College reading list (because several members happened to have it) as a starting point. But as time went by, they became less structured in their selection process. They, like many others, discuss titles and eventually agree on one.

Often yielding to impulse, the group stays with one author for a while or moves to a similar writer. "We love the freedom to linger," says Bryce, "when we find an author or area that is special."

Various book discussion programs are offered through Washington-area branch libraries, including some for the visually handicapped, the deaf and the hearing-impaired. At an organizational meeting the group participants, with the guidance of a librarian, choose what they want to read and discuss.

At the Hillcrest Heights branch, a group has been meeting for almost five years. Under the guidance of librarian Sue Uebelachker, the members have selected a variety of books, including some they admit they might not have read on their own. Among the works discussed: John Barth's The Sot-Weed Factor, T.H. White's The Once and Future King, Ralph Ellison's Invisible Man and Dostoevski's Crime and Punishment.

Finally, participation in a book group enhances the reading experience because it provides a framework for analysis. The different interpretations shared by group members can enrich the reading experience.

As a consequence, the reader usually finds herself or himself taking a closer look at the subject matter of the book and the literary style of its author. Members often come to meetings with notes, prepared to cite passages to support their points.

For those who prefer a more structured discussion format, the Great Books approach may be the answer. Since 1947 the Great Books Foundation, an independent, nonprofit educational organization, has sponsored a liberal self-education program through the reading and discussing of great books.

The Great Books Foundation publishes a four-book series that contains classical works of literature, philosophy, theology and psychology. In addition, three volumes of contemporary short stories and plays based on particular themes ("Search for Meaning," "Becoming Human" and "The Individual and Society") are available from the foundation.

By using what the Great Books Foundation calls the "shared inquiry" method, group members together try to determine the author's meaning. A trained group leader asks questions to stimulate discussions.

From the exchange of various points of view, participants say, the group comes away with a greater understanding of the work as a whole.