Last week I went to my five-year-old daughter’s first grade-school concert. The concert was held on stage, in a community centre theatre that looks exactly like a real theatre, complete with galleries and spotlights. Kids of all ages sang out of tune and, more surprisingly, in tune. Some of the expressions on these kids’ faces were terrified, others earnest. I made a great effort not to weep.

A twelve-year-old girl stood out. Like her classmates, she wore all-black. What distinguished her from the others was how much skin she showed. She wore clingy leggings and a black tank top, highlighting a hefty musculature. Because although she was skinny, this girl was strong. From halfway up the audience, you could see each arm’s tough little bicep, the swell of each tricep. You couldn’t see, but you could imagine, the sinewy strength of each forearm.

Because the school community is small, I know this girl informally. She’s a gymnast and, at twelve, she trains a minimum of four times a week, after school and on weekends. She’s dedicated. So, on one hand, she wanted to show off her hard work. What was clear from her body language was her lack of self-consciousness. On the other hand, she had that awkward tilt of the head, the small, unevenness of the shoulders typically affected by adolescent girls, which showed that she was still wrestling with her body image.

After thirteen years of practicing karate, running, swimming, and doing yoga, I’m blessed with a pretty strong figure.  And, until a few years ago, I was proud of my musculature. It symbolized my hard work. I considered it half sexy, half tough. (When I was twenty, my favourite film character was Sarah Connor, the Terminator’s toned nemesis in the movies by the same name). Then, two years ago, I started training for my black belt. My quads grew. This was okay: I could hide them under a pair of jeans. I was worried about my arms, though: they swelled until I looked like a mini sumo wrestler in drag. Now, I was more tough than sexy.

I asked my husband, “do you think my arms look big?”

He looked at me. “Are you crazy? They look good.”

I continued to worry. I perused women’s fashion magazines: their arms were matchsticks. If women in the fashion world worked out, they kept it in check. I considered my closet and wondered whether I should replace all tank tops with quarter-length-sleeve shirts.

Then I saw this girl on stage. Clearly she was struggling with uncertainties that were also mine: what to do when one is strong, in a culture that undervalues women’s physical strength and the mark it leaves on our bodies. Her smile, though, showed me that her regard for her body — not for itself, but for what she could do with it as a gymnast — was winning over other doubts.

I still worry about the size of my arms. But seeing this gymnast reminded me of what I like about my body, which is that it practices karate, and a lot of it. It made me happy, seeing that tough young girl on stage, her head up, her face flitting from tentative joy to all-out, radiant, red-cheeked pride.