Junko Kazukawa

Junko Kazukawa (数川 純子 Kazukawa Junko, born 1963) is a Japanese-born ultrarunner who currently lives in Denver, Colorado, U.S. A two-time breast-cancer survivor, Kazukawa competes in marathon, ultramarathon and cycling events. She was the first person to complete the Leadville series and the Ultrarunning Grand Slam in a single year.

Biography Kazukawa was born in Sapporo, Japan in 1963. After completing her primary and secondary education, she earned a master's degree in Kinesiology and Exercise Physiology. She moved to Denver, Colorado in 1988 and works as a trainer and coach for runners. Kazukawa began running marathons in 2000 and had completed 48 marathons and 11 ultramarathons by 2017, including such venues as the Boston Marathon, the Ultra-Trail Mt. Fuji and the Ultra-Trail du Mont-Blanc.

Kazukawa was diagnosed with breast cancer in 2005 and after completing a five-year treatment plan was diagnosed with new cancerous tumors in 2009. After undergoing a double mastectomy, she competed in the 2009 New York City Marathon five weeks after her surgery, while she was undergoing chemotherapy. In 2011, Kazukawa completed her first Leadville 100, as a fundraiser for the Susan G. Komen Foundation.