Terry Fox's Marathon T-shirt

Origin
Terry Fox was a Canadian athlete, heavily involved with sports from an early age. However, at 19 he was diagnosed with a cancer called osteosarcoma, spreading from his left knee. He had his left leg amputated and underwent several sessions of chemotherapy. Fox embarked on a 3300 mile across Canada to raise funds for cancer research. He ran the equivalent of a full marathon every day for 143 days until he was forced to stop when the cancer spread to his lungs. His hopes of overcoming the disease and completing his marathon ended when he died nine months later.

He was the youngest person ever named a Companion of the Order of Canada. He won the 1980 Lou Marsh Award as the nation's top sportsman and was named Canada's Newsmaker of the Year in both 1980 and 1981. The annual Terry Fox Run, first held in 1981 in his honor, has grown to involve millions of participants in over 60 countries and is now the world's largest one-day fundraiser for cancer research; over C$650 million has been raised in his name.

Effects
Worn in Fox’s training sessions where he learned how to tolerate and overcome the pain of running with a prosthetic. Wearing it allows the user to run great distances repeatedly while ignoring any pain. However, extended use will cause the user to contract a cancerous like injury within either their leg or lungs, making it medically impossible to continue running.