Snowshoeing - 2nd time

Tomorrow I will set off on a big snowshoeing adventure.  I have been out snowshoeing one time before and though I enjoyed the activity immensely, I was pretty red in the face after only a short time.  I now own snowshoes and hope they will pay me back on the investment by giving me some good cardio, and leg strengthening results.  I will let you know on Sunday night as I will be away from computers etc. for the weekend.  Wish me luck!  PS I hope to stay on my feet and not bang up any more knees....