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Before the workout, Lee Kuk Ju's waistline was measured to be 111 cm and Jo Se Ho's waistline was measured to be 100 cm. The instructor demonstrated a pli� (bending of the knees) as if you were the cork of a wine bottle being opened, giving strength to your inner thighs with proper breathing. He also put a plastic bottle in between their legs and asked them to crush it with their thighs while dong the workout. He recommended that you should do a 3-set pli� 8 times a day to see results. 

The workout seemed effective with Lee Kuk Ju's waistline becoming 108 cm and Jo Se Ho's waistline becoming 94 cm after doing 20 sets of the 'wine-opener' workout routine within 3 minutes.

Check out the workout routine above!