Career
She edged out her teammate Jung Seul-Ki to take a bronze medal by 0.31 of a second in the 200 m breaststroke at the 2010 Asian Games in Guangzhou, China, with a time of 1:10.22. Back qualified for the women"s 200 m breaststroke at the 2012 Summer Olympics in London, by eclipsing a FINA A-standard entry time of 2:26.61 from the FINA World Championships in Shanghai, China. Back shared a seventh fastest qualifying time of 2:25.76 with China"s Ji Liping in the morning"s preliminary heats to secure a spot for the semifinals.
On the evening session, Back missed out of an eight-seed final, as she placed ninth in the semifinal run by 0.21 of a second, lowering her Olympic time to 2:24.67.