During an interview with OSEN on April 7, Han Hyo Joo worried over "letting everything go," or baring the stripped down, unaffected version of herself on KBS's '1 Night 2 Days.' 

When asked about how it was guesting on the program, Han Hyo Joo answered, "I have great respect for everyone. The director, and all the staff members are incredible. My body felt like a bag of sand [after filming]. Just one day of filming, and I couldn't recover for three days. I just lay there, unable to do anything." 

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The actress continued, "The filming was so fun. But I'm a bit worried. I let everything about myself go. As the airing date neared, I felt more nervous than I did for a movie premiere. I thought, 'What should I do?' and worked until the point of exhaustion even though I only needed to put in a normal amount of effort."