The handsome actor Joo Sang Wook gave his fans a sneak peek at the good stuff on the latest episode of 'Qualifications of Men'.

On the latest episode, the cast members teamed up to take on the 'Iron Man' - a sports event which includes swimming, cycling, and a marathon.

At the swimming section, the other members pressured Joo Sang Wook to take his shirt off, which he obliged with some hesitation.�Although everyone was surprised and envious at his musculature, he himself was embarrassed, asking the cameras to stop filming.

Meanwhile, actor and exercise fan Song Il Guk joined the cast for the 'Iron Man' episode.

Source: Newsen via Nate