Girl looks me up and down?

One time at the gym, I turned to my right and saw a girl looking at me and we made eye contact. Right after she scanned down my body quickly going down to my toes, then she looked back up at my eyes and looked away. What does this mean? On this day I was wearing my tanktop which I dont normally wear, she normally stares at me anyway, But she doesn't neccesarily look me up and down like that. So I wonder if it had to do with my muscles being exposed? This time it felt very sexual? What does this mean?

Girl looks me up and down?
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