Winter Training

So, what does a person do during winter months in the North country to get in shape for biking across the country? Beats me....I have never done this before!
I have developed my own array of muscle building and cardio training. I have the following equipment that I trade off on.....
---A loaned Schwinn AirDyne from brother and sister-in-law, Rick and Bonnie.
---A loaned bike trainer stand that I have my trail bike on, from Pete Drost.
---My own treadmill for jogging/walking.
---My son's rowing machine.
---Arm weights.
---Exercise pad for doing back and abdomen strengthening exercises.

I hate jogging, so I have been spending most of my sessions on the Schwinn AirDyne, riding 20 miles at level 3, which takes about 70 minutes. I have found this to be harder than level terrain bike riding and is a real workout, as if you were riding uphill the whole way. This gets my heart rate up in the 150+ area. I am trying to do this 3-4 times a week.
I have dropped about 15 pounds since last Fall and hope to trim some more off before Spring comes and the more enjoyable outdoor training begins.