Where to start with the incredible Junko Kazukawa? This two-time breast cancer survivor is an ultrarunning legend with twenty-one 100-mile ultras in the bank, multiple 50-mile finishes and a road marathon PB of 3:20 – and at 59 years old, she’s not stopping yet!

In 2015, at the age of 52, Japanese-born Junko was the first person to complete both America’s ultrarunning Grand Slam and the full Leadville race Series in one season. To break this incredible achievement down, within a four-month period, Junko completed the Western States 100 Run, Vermont 100 Run, Wasatch Front 100 Run, and the Leadville 100, alongside the Leadville Marathon, 50-mile run, 10K run and the Leadville 50-mile and 100-mile Mountain Bike events. Amazing. 

Junko’s running CV is vast, but notable mentions include her finishes at the UTMB, Ultra Trail Mount Fuji, and the Ultra Fiord Patagonia, where she was the second woman to cross the line. Thankfully for the American ultrarunning community, Junko shows no signs of stopping anytime soon. In fact, check out her 2023/24 plans in our interview below. Junko also shares how her second breast cancer diagnosis led her to take on her first 100-mile event, and we cover her training, race strategies, and her endurance running coaching business, which she runs from her home in Denver, Colorado.