Women's locker rooms can be both freeing and intimidating. A locker room can be a retreat, a place to toss aside the worries of the day, but it is also where our flaws become most apparent — and where most of us can't help but wonder how we “measure up.” Leslie Goldman spent five years talking with women of all shapes and sizes about their body image, from taut twenty-somethings to heavyset seniors. Goldman was invited to discuss her book “The Locker Room Diaries” on the “Today” show. Read an excerpt:

Introduction:  Warming Up
When I learned Crunch Fitness had installed peekaboo showers in their locker rooms, enticing members to watch their fellow gym-goers soap up from behind sil­houetted glass doors, I was amused and, admittedly, a bit ­intrigued.

When 24 Hour Fitness launched a billboard campaign featuring an alien along with the proclamation, “When they come, they’ll eat the fat ones first,” I was horribly disturbed.

But when I discovered Women’s Workout World had a “No Nudity” policy in their club’s locker rooms, I was blown away.

“We deal with women from all walks of life, all different shapes, cultures, and religions,” explained CEO Shari Whitley. The “No Nudity” policy, she believes, fosters a nonthreatening atmosphere, one that especially helps women who have issues with body image.

So there it was: Women’s self-esteem has become so needy that although some of us feel it necessary to perform a wet burlesque show for the weight room while we shower (“Oops, I dropped the soap!”), others are so fragile that “No Nudity” clauses are now needed ... in locker rooms.

I knew something had to be done.

That’s why in the time it takes to read this introduction, I’ll likely have witnessed more naked women up close and personal than the average adult male sees in his lifetime. Yes, from gazing at gazongas to poring over pedicures, for the past few years I have immersed myself in the locker room of my gym, scribbling notes, eavesdropping, stealing glances, and, when the situation called for it, just downright, blatantly staring. Some might call this sort of behavior rude — invasive, even. I call it research.

NBC VIDEO 'I'm so fat!' Women and body image issues July 10: The "Today" show's Natalie Morales talks with Leslie Goldman about her new book "Locker Room Diaries." Today show

What I conducted, essentially, is an ethnography of the ladies’ locker room (and in the process I raised more than a few male friends’ and colleagues’ eyebrows). It began innocently enough: I was just starting graduate school, earning my master’s degree in public health with a focus on women’s health. Having grown up in the impenetrable bubble of north­western suburban Chicago, where taking a baseball bat to a mailbox is cause for a town-hall meeting, I was new to the city and needed to join a gym. A nice, safe gym — my only requirement being that men did not lift weights in cut-off jeans and construction boots. Did such a thing exist?

I found a great place, a relatively expensive health club with all the amenities: from disposable razors, lotion, and mouth­wash to an onsite manicurist and Reiki healer. I mean, there was even a rooftop sundeck with a tiki hut and bar.

But for me, the real action was in the locker room. Within my first few days of working out, I started to take note of the insults women hurled at themselves like drunken Cubs fans, the public trading of body flaws like so many stocks and bonds. In what began as a sort of informal thesis, I started carrying my faux leopard fur-covered journal in my gym bag. Every day in that locker room, I would scribble down what I saw and heard. And in a culture where women are essentially trained to loathe their bodies, it wasn’t long before I had a diary chock-full of anecdotes and stories — some of them disheartening, some inspiring, but all poignant.

Take, for instance, the attractive, slim twenty-something woman who approached me from behind as I applied my lipstick one evening. She wore a silver two-piece bathing suit, apparently ready to hit the hot tub. As she walked closer and closer, I eyed her toned physique through the mirror and felt a twinge of envy. Just as the thought, “I wish I looked like that in a metallic string bikini,” traveled through my head, the woman slapped her thighs and shouted out in disgust, to nobody in particular, “Ugh — I’m so FAT!”

Was she searching for some sort of sick camaraderie from me? Or was this self-deprecating comment merely rhetorical? Regardless, the message was clear: This woman hated her body, imaginary flaws and all.

From the women with immaculate physiques who change in the bathroom stalls to avoid imagined public scrutiny to the heavier women who stroll around naked without a care in the world; from the women who wax everything — and I do mean everything — to women who shave down south only for their yearly gynecological exam; from breast implants and mastectomy scars to bellies swollen from pregnancy and asses sagging from old age, every body part and every owner has a story to tell — and a lesson we can learn.

When we are naked, we are at our most vulnerable — physically and emotionally. When we are naked, there are no Miracle bras to lift our 34Bs to magnificent heights, no control-top panty hose to smooth away the dimples, no high heels to coax our calf muscles out of hiding. Without the armor of clothing, we fall prey much more easily to low self-­esteem, personal insecurities, and the scrutiny of those around us. Like animals in the wild, we are in our bare, natural state, with nothing to hide us except a measly rectangular strip of towel. Skin hangs and wobbles, blemishes emerge, hair sprouts from places we didn’t know it could grow. Ah, yes, fluorescent lighting. From the self-deprecating comments I continue to hear uttered by and between women, the bodily obsessions and emotional vulnerability reflected in the mirror and on the scale, I have come to realize that the locker room is where women literally let it all hang out. Beneath the un­forgiving lights and amongst the stolen glances from fellow females, I’ve gained a new understanding for how what goes on in the women’s locker room can be viewed as a distillation of our body-obsessed society’s impact on women.

I believe it’s time we tame the disparaging inner demon that paralyzes so many women into a state of broken body image and delve deeper into the question of why — why have we succumbed to this culture-induced cacophony of “if-onlys”? If only I could be thinner. If only my breasts could be as firm as hers. If only my ass could be that high. If only I could be that sexy. That curvy. That waif-like. The adjective doesn’t even matter, so long as the grass is greener (and neatly trimmed into a Brazilian bikini landscape). Though these locker room lessons — whether about growing older, giving birth, getting cancer, or braving therapy — may differ, the ultimate maxim will emerge universal: Slay the demon, screw the scale, and live large, no matter what you weigh.

Through my (mis)adventures, the locker room has become my second home. It’s where I shower and shave, gossip and gab. I venture to my gym five, even six times a week. (Although sometimes exercise isn’t even required: I’ve been known to indulge in an occasional “executive workout” — a sauna and a shower — just to get my fix.) After each sweat-soaked, soul-cleansing workout, the locker room is my retreat. Inside, I and scores of other women peel off our clammy sports bras and strip down to our skivvies, our tired bodies begging for a warm shower and perhaps a reprieve from self-reproach.

But much more than that, the locker room is where I have learned about body image, the female form and the various neuroses that afflict it — more than any college anatomy class or well-worn therapist’s couch has taught me. Time after time, I have listened as women chastise themselves and trade insults with girlfriends, sisters, or even their children, uttering the sorts of statements that would be deemed mentally abusive if a man were to spew them to his wife.

Having watched too many friends battle anorexia, bulimia, and compulsive exercising, I have seen the ways poor body image can wreak havoc on a young woman’s physical and mental health. They are just a few of the eight million American women who struggle with a diagnosable eating disorder, according to the National Association of Anorexia Nervosa and Associated Disorders — and that number does not account for the untold others with disordered eating and distorted body image (“body image” referring to the way a woman perceives her physical appearance, as well as how she thinks others see her).

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