could be sexual harassment, especially if you're alone in a dark street at night, no one else around, and your victim has no way to escape, as you're blocking the alley exit
even if the comment is covered by the 1st Amendment Free Speech Clause, you are still liable civilly in a civil lawsuit for inflicting emotional distress, as well as subject to being fired from your job for violating their policies.
If you escape the criminal penalties, the civil penalties may be as bad or worse.
"you look like you've been working out" "what do you do, 300 pound bench lift?" See an episode of Fast & Furious, as the fast talker talks/flatters Brazil employees, to try to get into a crime lab evidence room,
or "You should enter the Ms. America contest" or "she looks really hot" (see the movie A Team, as Lt. Peck tries to act brave as the woman's husband is about to set Lt Peck on fire, so hot Mars can see it, while stuck in some tires, would probably be ok, unless the darker alley scenario arises. Although Lt Peck overplayed his hand and almost got himself killed, but for the amazing last minute rescue of BA and Col Smith.
There are criminal, civil and practical penalites, all which could be major, & fatal, no matter how "innocent" the comment or context.
On the other hand if a woman commented on a man's body, the sky is nearly the limit on what she'd get away with. As long as it was positive. IF negative, not so much, but not so badly as the gender reverse play. Even if negative, the jury or judge would laugh at the guy for filing a lawsuit, and he'd be laughed out of court and in the news media as a total wimp.
With a man commenting negatively on a woman's body. He's playing with fire. Never ask a woman if she's pregnant, or assume she is, no matter how seemingly obvious. TV show's Big Bang's fictional Cal Tech Professor Sheldon Cooper admitted he learned that lesson and he knows nothing about women, but maybe that one lesson
Call it a double standard or natural gender differences, it's very serious reality, not to be ignored, without major potential adverse consequences
But if your comment on someone's body is for purely health purposes, medical, not aesthetic, such as to point out some possible skin cancer, you get major credits, especially if you're right or close to right.
Or you're a football coach telling his lineman to eat more to fatten up, it's all part of the game . All's fair in love & war & football. (who ever came up with that original maxim, it was before they invented football, but maybe long after Sumo wrestling)
Context is everything. Or nearly everything.