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They're known for their model-like proportions, but the leggy beauties of AOA took the MCs of Weekly Idol by surprise when they measured their tiny waists.
On last night's June 24 episode, Jimin and Mina took part in a challenge to see had the smallest waist.
Both seemed to get into the spirit of the competition as they struggled to suck in their stomachs and contort their tiny bodies as much as possible while the other girls, particularly Choa, helped wrap the measuring tape around their bodies.
First up was 24-year-old Jimin, who had recorded an impressive 19.5-inch at the narrowest point of her waist.
But taking the grand prize was Mina, 24, who shocked everyone when the measurement was a minuscule 17.9-inches!
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AOA are currently promoting new single "Heart Attack" and running from show-to-show, so it's no surprise the K-pop idols have all lost weight. We just hope they stay healthy!