Jane Fonda is haggard. Jane Fonda is harried. Jane Fonda is hungry. Jane Fonda looks great.

"You're not going to take too many close-ups," she says to the photographer, as she settles her 47-year-old sacroiliac into an uncompromising chair. "I'm soooo tired."

It's tough being a Modern Woman with Something to Promote. "Donahue" in the morning, local TV in the afternoon, radio and print in between. It's been a stressful day all the way around. And no time for Jane Fonda's Workout.

She has a new book, "Women Coming of Age," and a new fight. It's against aging. You've got to hand it to her. Fonda will not accept defeat. She is indefatigable in the face of the ultimate inevitabilities, this prophet of the new puritanism. And you should look so good.

"I'm not going to apologize for the fact that I look very well for my age and that I'm extremely healthy," she says, munching an apple. "I worked hard for it and I'm proud of it and I'm not going to apologize for it. Millions of men and women in this country have done my program and read my books and have been turned on to health and fitness. I think it's wonderful. I haven't heard too many of them complaining, 'I want this program put forward by someone who's dumpy.' "

She is sitting in her hotel suite overlooking Central Park. Down below, a whole city is on the move -- mostly, it seems, in sweats and sneakers. Fonda isn't just part of the movement. She is the movement. If you want to trace the changes in American culture over the last 20 years, all you have to do is look at her. She is a lightning rod for a generation whose rhetoric has evolved from Burn Baby Burn to Feel the Burn. And now: Hot Flashes (as of the first printing, she hadn't had any). As goes Jane, so goes the nation.

"In all my probings of the biological reasons for getting older," she writes, "I've found that the process of aging is, to a large degree, negotiable."

Negotiable?

Isn't middle age about spreading and sagging and accepting it gracefully? Isn't the message of this glossy new tract with her glorious kisser on the cover the same insidious one that middle-aged women have been subjected to all along? That unless you look 22 when you're 50, unless you look like Fonda, you've had it?

Don't women buy her book, or Raquel's or Victoria's or Sophia's, because of the implicitly cynical promise that somehow we'll all end up looking like her?

Fonda is calm. Fonda is tough. She's heard it all before.

"If we buy into the demands to conform physically to some fashionable image of someone else, that's getting on a treadmill of anxiety that I personally have been victimized by," she says.

Victimized. She has talked about the fact that she was once bulimic, keeping her weight down by forcing herself to vomit.

And there were critics who felt that her sex-object role in "Barbarella," back in 1968, was the work of a Svengali husband-director, Roger Vadim.

She's come a long way from bulimia and "Barbarella," but some might argue that she is still selling her looks.

"I'm sure there are some people who would couch it in those terms," she says."I don't know how to answer this. There's no question 'On Golden Pond' helped sell my Workout program because people saw me in a bathing suit. So what?"

Furthermore: "I'm not ashamed of 'Barbarella.' I think 'Barbarella' is a great camp movie. A great cult film, a lot of fun. It was not sexist, either, by the way."

Back then, in the days of "Barbarella," she never thought about getting old.

"No, no," she says. "Weren't we immortal? I think we were immortal. Yeah. The true, true recognition that I was going to die was when my father was dying, to be perfectly honest. When your parents are still alive, there are barriers between you and your own mortality. When they die, man, you step up to the turnstile. It's your turn next. When people who were your idols, the people you've hung on to for surival, your parents, go, you know you're not going to be exempt. That's when you really know."

There was no epiphany, no one moment when she realized it was happening to her. "I think it happens sort of slowly," she says. "It creeps up."

She can feel it in her bones. "I'm like Katharine Hepburn," she says. "It won't be the heart and lungs and vital organs. It'll be my joints and bones."

She noticed the gray hairs first. She doesn't dye and she doesn't yank. She streaks. Then she noticed the wrinkles, and then the ease with which she could put on weight. "That's real noticeable," she says, but refuses to divulge the pertinent figure.

There are other figures available, however.

The original "Jane Fonda's Workout" book has sold nearly 1.5 million copies, according to her publicist. The "Workout" videotape is the top grossing video of all time. Her husband, Tom Hayden, may be the only person in America who hasn't done the Workout. He runs, plays basketball and works out with the Los Angeles Dodgers every spring in Vero Beach, Fla.

The new book, coauthored with her friend Mignon McCarthy, has sold more than 300,000 copies since November and is in its second printing. It offers pragmatic tips on how to negotiate with the aging process, scientific research on nutrition, menopause and beauty, a new "Prime Time Workout" designed for the over-35 set, and Fonda's personal account of coming to terms with middle age. She believes in being prepared.

"It's from the heart," she says. "It's personal. I admit I'm afraid of about getting old. First I admit I'm getting old-er. You're not supposed to do that when you're a movie star."

There is something ironic in the fact that the chatty feminism of her text is so acceptable to women who would have once repudiated her, who would have repudiated the message if it came without the gloss of a Hollywood veneer.

"You know what matters? Will they learn something. I'll stake my life on it: reading my book they will learn something. I don't care why they buy it. It's like I didn't care why they would come to hear me speak against the war or whatever as long as they came away with information.

"It is true when a movie star writes a book that's not called the Feminist Workout and is not being marketed as a feminist book, that it will have a wider audience," she says. "And you know something? There isn't anything in there that most women don't agree with. The fact is so many of us are feminists and don't know it but are maybe scared of the word."

There are certain things, she admits, that you just can't prevent: wrinkles, gray hair, decreasing bone density. She is unalterably opposed to cosmetic surgery. But she refuses to capitulate. She is down there in the trenches fighting every day.

"I'm 47," she says. "There's no reason why someone has to look 65 when they're 47. Some people feel, 'So what? I'm going to die eventually. Why not smoke? I'm already stressed out. Why not drink coffee? Life is hard and I need to relax. Why not drink a third of vodka? I'm getting old anyway. Why not put on 40 pounds?'

"Well, God bless them. They may be the exception that proves the rule and live to 100 and have a happy life. But chances are they won't. Chances are they won't be happy about themselves. Chances are they will not have a good-quality life and will die sooner, but it's their right to live that way."

"I like the way I look better now," she says. And who can blame her? "I have more character. Where? In my face. It's a gestalt. I just think I have more character than I did then. Since I'm not conventionally beautiful and never was, character is very important."

She has never thought of herself as beautiful. "I don't perceive myself as being ugly," she says. "I think I'm more average."

Her laughter is a welcome interruption. But there is no doubting the seriousness of her purpose. "Aging is harder for women who are perceived as being beauties, and whose lives and careers and social relations are based on their physical beauty," she says. "That's not the case with me. I don't have beauty-type roles. I almost never have, with a few exceptions. If I was pretty it helped, but the roles were not about being beautiful. My profession has never been predicated on my being a glamor girl."

She has just finished shooting 'Agnes of God,' in which she plays a chain-smoking psychiatrist, and is awaiting the script of a new movie called "Old Money," which is about old money. She and her brother, Peter, will costar.

Life is still a vibrant, vital, dynamic whirl. Time is precious. She is running late. Her plane leaves at 6. One last question. America wants to know: Does Jane Fonda have any cellulite?

"That's personal," she says. "If America is worried about that, America is in big trouble."