The Bottom Line

So you’re thinking that great-looking abs are the body part du jour.

Guess what, chicken butt? It’s the gusto for gorgeous glutes that traditionally shapes our idea of what the perfect body should look like, an enthusiasm going back to the Stone Age when well-rounded female carvings meant fertility.

“Historically women have based their self-esteem on their appearance. Buns are a target, just like breasts, because it’s a visible part of the body and connotes sexuality,� says Kathleen Mojas, a Beverly Hills psychologist who often deals with body image issues. “It’s an obsession propelled by history, fashion and media.�

Getting the lead out has launched an entire industry for at least 15 years. The granddaddy of backside videos, the “Buns of Steel� series, has sold more than 13 million copies. That includes 15 tapes alone devoted to firming your lower half.

Unfortunately, Mojas says, in our quick-fix society, people think changing their butt size will ease their inferior feelings. That said, the sorry-ass truth is, looking great in a pair of jeans does do something for the ego. But you can forget the notion of nice buns in 30 days.

A perfectly toned tush depends largely on genetics, with an assist from exercise, diet and motivation, experts say.

Here are the facts.

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Spot toning--the idea that you can exercise a certain part of your body and lose the fat--is a myth, says Richard Cotton, exercise physiologist and spokesman for the American Council on Exercise.

“The limitations of spot reduction are that we are genetically predisposed to where fat comes off first. The good news is, we tend to lose weight in our face first. The bad news for women is, fat generally comes off the rear, hips and thighs last.�

A lot also depends on body type, Cotton says. “Women who are naturally thin or athletic get quicker results from a buns-focused workout. The secret to fanny-firming exercise tapes is that the models who do them have pretty good-looking buns to begin with.�

Storing backside fat is a gynecological survival tactic, says Susan Bartlett, associate director of clinical psychology at the Johns Hopkins University Weight Management Center in Baltimore. “Sustaining a healthy reproductive cycle requires body fat. It’s our reproductivity that decides how much fat will go to our backsides and when it will be mobilized.�

Women often find they gain more weight in their bottom and hips during a pregnancy. Bartlett says the body counts on those fat reserves and activates them first under two conditions: toward the end of a pregnancy and during lactation. For the same reasons, taking hormones such as birth control pills or hormone replacement therapy can also play a role in gaining backside fat.

Researchers theorize that many American women maintain extra backside fat after their pregnancies because they tend to breast-feed for a shorter time compared to women worldwide.

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Inheriting your parents’ unhealthy eating and exercise habits can also give you a big ol’ butt, says fitness expert Kathy Smith, whose two latest exercise videos in “Functionally Fit� (Warner-Vision, 1996), emphasize lower body firming and fat burning exercises.

Bodybuilding is a science, says fitness expert Joyce Vedral, author of “Bottoms Up� (Warner Books, 1995). She says “pyramiding� and “super-sets� are essential to building and sculpting muscle quickly. With pyramiding, the weight used for each exercise is increased slightly in each set of three. Super-setting means to alternate between exercises for two body parts--for example the butt and thighs--without a break between the two, then repeating the process.

“Effective workout routines are progressive,� adds personal trainer to the stars David Mastorakis, who runs Fitness Thorough Science in West Los Angeles. “A nonactive person will see some initial results, but building a muscle requires resistance. Which may initially mean the resistance of your own weight, but should eventually mean adding weight.�

Important to the fanny-firming formula is reducing fat either through aerobic exercise or diet, preferably both. Cotton encourages choosing exercises with dual benefits. Climbing, bicycling, walking and running not only tone the gluteus maximus and surrounding muscles, but work on overall aerobic fitness while burning fat.

Remember that working on your backside goes beyond the rear view. Not only does muscle burn calories faster than fat, but strong glutes help posture, balance and give you a head start in most sports. But more important than balance in your body is balance in your life, Cotton says.

“Having a tight bottom doesn’t make you healthy. It’s much more healthy to be happy with yourself than constantly self-critical.�