Rosie Brennan, a three-time Olympic champion in cross-country skiing, has announced her end to her career at age 37. Brennan had been battling health issues, including achy joints, soreness and random cramps, and estimated she saw at least 10 to 12 doctors. She began her career with a deep appreciation for challenging myself and finding joy in learning. Brennan competed in 31 total Olympic or World Championships races. Her 279 World Cup starts are second in U.S. women’s cross-continental skiing history. She plans to enroll in a master’�s program for Liverpool John Moores University in England.