Open a magazine and you'll find one Madison Avenue conception of the modern man: brawny logger in wool shirt and boots astride a mountaintop, his jutting chin challenging Mother Nature as he puffs away on a Camel.

Peer into the home of a young Washington couple and you're likely to see another version: the husband vacuuming, doing the laundry or cooking.

The macho image may be the one many men grew up with, but an increasing number are stepping down from that mountain to change a diaper or to push a dustmop.

American men, it is obvious, are changing -- whether they like it or not.And some most certainly do not.

"I'll help," retorted one man when asked by his working wife to pitch in with the chores, "when you're bringing in as much money as I am."

But when a change in attitudes has occurred, it can be attributed largely to the women's movement.

Women who are putting in eight or more hours on the job -- and their paycheck is needed to cover the mortgage -- are no more eager than their husbands to cook dinner or do the dishes. To keep the household running, men are finding that -- either voluntarily or after persistent prodding -- they have to do their share.

"It is," says one Washington husband, "only fair."

Fair or not, men are apt to be confused about what they see happening to their homelife -- or angry at the "male-chauvinist-pig" names and the blame for keeping women subservient in the past.

"If it was my fault, I was doing what I was taught to do," complains men's liberationist Richard Haddad of Columbia, Md., editor of "American Man."

"I don't remember entering any conspiracy with other men. I was taught by my mother. Blame my mother. My father wasn't home to raise me."

"We are," say Alexandria psychologists Helen and Wayne Reznick, "in a cultural revolution in sex roles. You can't change women without changing men."

It may, they say, "take several generations to reduce the strains."

But what, asks feminist leader Betty Friedan in a Redbook magazine article, "are men's rewards for giving up some of (their) power?" The benefits "aren't that obvious at first."

What, then, has the women's liberation movement meant to men?

What have they gained?

Lost?

These questions were put to a number of people -- including leaders of both men's and women's liberation movements.

Apt to anger feminists is the answer of one 40-year-old Washington writer/bachelor.

"It is," he says -- and he means it as a tribute to the women's movement -- "easier to get laid now, in a grown-up way."

The most difficult thing "was to learn to drop the word 'girl' from my vocabulary."

Another mid-career male sees a darker side to the influx of women in the workplace.

"There is a tendency," he says of affirmative-action programs, "for some companies to hire able women over able men of the same qualifications. It's harder to get ahead."

Bethesda lawyer Edward T. Love, whose wife is a partner in an insurance agency, takes a more positive view:

"Women are getting a good idea of what men have been going through on the job." He says women now can be more understanding about their mate's career hassles -- as they expect men to grasp the hassles of housekeeping.

The wife's income, says Quincalee Brown, executive director of the American Association of University Women, has relieved the male of sole responsibility for the family's income.

"It's just so hideously expensive to live. It's very hard to support a family alone."

The financial stability of two salaries also means, she says, that if either spouse decides to go back to school, make a career switch or start a new business, the family has that second income to keep food on the table.

Another benefit, suggests Brown, formerly director of the Montgomery County Commission for Women, is that the husband who pitches in with housekeeping and childcare is less likely to find himself involved in a divorce.

It is the "domestic battleground," says the Reznicks, where the tensions tend to erupt -- "who cleans the toilet, who changes the diapers."

But an increasing number of men are realizing "that they are important, too, as parents."

It beats what they call "the werewolf relationship:" Father shows up only at night and the children are sent off to bed "because Daddy's had a hard day."

The impact of our cultural transition can be subtle. Take the example, says Eleanor Smeal, president of the National Organization for Women, of the man who thinks choosing wallpaper is solely a woman's responsibility:

"If you're redecorating and the man doesn't like it, he might live for 20 years with a color he doesn't like." Her father, she says, "never had a chair he was comfortable with in his home. He let Mother do that because that was the way to be."

For Smeal and her husband Charles, a metallurgist who followed her to Washington when she took her NOW post, sharing household and work responsibilities gives both spouses "more control over your environment."

She recalls a time when her husband would call her from the kitchen for each step in a recipe. "He has a Ph.D. 'You could be more creative cooking,' I told him. I learned."

One thing that has troubled her is that women tend "to raise their girls as feminists, but their sons more traditionally. We feel that is setting your son up for trouble.

"If a man is going to expect a traditional wife" in the year 2000, "she isn't going to be around."

Many men -- though they may dream of a willing harem -- find they enjoy a mate who has a career of her own. Her work associates broaden their range of friends. They can share career concerns.

"It makes her more interesting," says a middle-aged Washington male.

As women find they can express their assertiveness without losing their femininity, men are learning they can be both sensitive and masculine.

"Men feel that they can be more varied," says Wayne Reznick. "They don't feel they have failed if they are not macho."

"Being able to express their emotions," adds Helen Reznick. "That's got to be a plus."

One of the big challenges for men today, she says, is dealing with the disparity between their new role and old image. "TV says women want men to be macho. But women tell me, 'I want some sensitivity from him.'

"It's a dilemma."

Says the bachelor writer: "The masculine dominance thing is a drag."

Men's liberationists believe the women's movement has reached its peak -- that now it is time to deal with important men's issues such as shorter life expectancy.

"If women are angry at being deprived of income," asserts Fredric Hayward, Cambridge, Mass., founder of Men's Rights, Inc., "what about men being deprived of eight years of their life? Why should I live eight years less than women?"

Still he credits the women's movement with teaching "me that things could be done about sexism."

"There's no question that the women's movement opened up our minds as men to the subject of liberation from sex roles," says Haddad, a founder of Free Men. That was "Act I. Act II is going to be the flip side."