Yes, you could either purchase the Diplomat America travel insurance plan with sports cover on a trip-by-trip basis or for the full 5 months. However, please note that there is no coverage on the Diplomat America in Canada for you since you are a Canadian citizen.
The Diplomat America overseas sports travel insurance plan is what you want to use since you will be traveling in the U.S.  It will cover you outside of Canada and anywhere in the world, including the U.S.
You will also need to add the “sports rider” to your policy and include the sport(s) you want covered, like bobsledding.