f(x)'s Sulli is going to share her tips for weight loss that she had to "Rum Pum Pum Pum" up for the group's latest comeback on the upcoming episode of SBS' 'Star King.'

For the upcoming 'Diet Show' special, Sulli discussed the 'plastic bag diet' that helped her get into shape. Popular in Japan, the plastic bag diet consists of blowing up a plastic bag and continuously kicking it into the air using your knees or feet. 

Other guests also joined in and revealed their tips to toning up on the summer special episode. 

To learn more about Sulli's tips, check out the upcoming broadcast airing on the 17th at 6:20PM KST!