The sky in Seoul has been looking terrible recently.It is said that this is due to fine dust. Although I always wear a mask when going out due to the rising trend in influenza cases previously. But lately, it's clear that everyone is wearing masks. A study found that exposure to fine dust increases the risk of developing kidney and prostate cancer. However, as it has been confirmed that regular physical activity does not affect the development of the cancer, it is necessary to exercise regularly even indoors on days when fine dust is high. And also hope the view of the sky will be better soon.