I am an adult. I pay taxes. I vacuum, sometimes. I buy the fancy toothpaste. I do all those things a grown-ass woman should do, which now includes a reasonable amount of exercise on a regular basis. Yet, the second I get to the gym and hit that locker room, well — I'm in the locker room again.As a kid, I was never pelted with tampons or subjected to boob-shaming by my peers after gym class. Sure, there was plenty of teasing and name calling in the halls as I was growing up an almost-but-not-really chubby kid before hitting an early puberty hard right around third grade. But, in the locker room, it was my own eyes that pried and compared and loathed what they saw in the mirror: a wonky, round girl jammed into school gym shorts that were clearly designed for the hipless. Things only got worse when we hit the soccer field and I watched my stick-thin classmates leap around like baby gazelles while I tried inventing a new way of running that somehow kept my butt from bouncing. Instead, I looked like I was practicing an elaborate pantomime of cross-country skiing. It did not catch on."Gymtimidation" may be the most irritating buzzword I can think of, but the phenomenon is real, and we've likely all been grappling with it since the moment we discovered other people had bodies, too. When I walked into Equinox a little over two months ago, admiring the gym that would help me help myself out of this fitness rut, I was a little "gymtimidated" (ugh, my kingdom for a new word.) The facilities were gorgeous (they have Kiehl's in the showers! For free! For me!), and the clientele, I had to assume, were better than I. After all, they were already coming here on a regular basis, were surely Zumba'd out the yang, and probably wore sports bras personally fitted by their best friend, Gwyneth Paltrow.Oh yeah, and I was the one afraid of being judged. I grabbed a locker and carefully assembled my workout clothes on the bench so I could put them on as fast as possible. Hiding "behind" the 10-inch locker door, I jumped into my (new fancypants) gym wear, put my head down, and darted out onto the floor. Out there, all I had to worry about was being the chubby girl on the elliptical, and that was one shame I was ready to let go of. At least if I was on the elliptical, working on my body, I could hold my head high-ish. Forty-five minutes and 11 Beyonce songs later, I headed back to the locker room and realized, as ever, that I was a total idiot.There were skinny women, and there were baby gazelles. But there were also a vast variety of female bodies, all in various states of undress — none of them trying to hide inside their lockers. It was another lesson in grown-ass womanhood: Life is not middle school, unless you want it to be.