Actress Lee Si Young demonstrated her extreme passion for sports once again as she decided to participate in a marathon, regardless of her 5-month pregnancy.

On September 21, a representative for Huayi Brothers stated, "Lee Si Young will be participating in a small marathon competition."

The actress even recorded her process by posting on her Instagram page, proudly taking a stroll at the Han River Park.

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Upon seeing this, many fans expressed their concerns for the star, Lee Si Young wrote, "Ever since I've been practicing, my body feels lighter and my records look great.  Of course, I have been following instructions from my obstetrician and medical doctor.  I've also been cooperating with other medical staff in safely preparing myself with weight training and running routines.  I am steadily getting ready for the marathon. (There have been so many concerning messages lately)."

This hasn't been the first time Lee Si Young has been in a marathon race.  Meanwhile, she will be tying the knot on September 30.