First lady Michelle Obama serves herself some salad during a dinner at an Olive Garden restaurant in 2012. (Carolyn Kaster/AP)

It’s true what they say about Michelle Obama. She has amazing arms. I saw this up close when she unfurled her bare right limb in front of me Thursday night, while the two of us were doing tapas at the jumping Barcelona on 14th Street NW.

Clearly the first lady works out, clearly she moisturizes and clearly L’Oréal should hire her as its pitchwoman after she leaves 1600 Pennsylvania Ave.

“Ma’am, you rock,” I wanted to tell her, even though I was seated a table away from her party of eight, which included White House chef Sam Kass, and was separated by a table occupied by two Secret Service agents. (They ate, too, but didn’t drink anything stronger than soda.)

A food fan who has eaten around the world (Le Diplomate, Cafe Milano, Zentan) around town, the first eater’s better half and I hadn’t exactly planned on seeing each other. She was at Barcelona for what looked like a celebration, seated in the back of the Spanish restaurant’s private room; I was there for the last of three visits in my role as food critic for The Washington Post.

To be clear, our eyes never met. Throughout dinner, Mrs. Obama sat facing the rear wall, and not once during my 90 minutes in the restaurant did she turn around. Her attention was totally on the three men and four women who had joined her for dinner. Only when a server dropped something to her right did she turn in the direction of the crashing noise, and then only briefly. The dark suits next to me, on the other hand, stopped chewing and fixed their gazes on the situation until they deduced the problem was something that didn’t require retreating to an undisclosed location (“Let’s really move!”), but merely a sweep or three of a broom.

Going into dinner Thursday, I knew it was going to be different from my other taste-tests. A knot of people at the restaurant’s entrance included more than staff trying to retrieve dishes from the open-air patio, drenched by a monsoon-like­ rain. “Can I check your bag?” a Secret Service agent asked the woman in front of me. “We have a dignitary in the house tonight.” Beside him was another man, who had a wand and a question for me. “Sir, do you have anything in your pockets? Keys? A cellphone?” Three more sober suits guarded the open entrance to the rear dining room.

As soon as I sat down, I spotted the reason for the abundant security. Even with her back to the crowd, the ­FLOTUS’s sleek coif, sleeveless dress (turquoise) and model posture gave away her identity.

My first instinct was to tweet the sighting — #TheSheBearIsLoose. My second impulse was to give the first lady, who enjoyed wine and dessert during dinner, her privacy. As it should, my news sense prevailed.

I had a third thought, too: Draped across a companion’s chair, Michelle Obama’s arm was the best review Solidcore — the workout studio that the first lady reportedly frequents — could ever hope for.