An extraordinarily simple way to burn calories and build strength while inside is to keep a pair of hand weights (three pounds, five pounds, or ten pounds, depending on your strength and experience) or resistance bands by the TV. If you don't own hand weights, consider using soup cans, old milk jugs filled with sand, and other homemade weights.

If you think that lifting weights will be too distracting during your favorite show, try lifting only during commercials. Doing this gives you starting and stopping points (start lifting when the commercials begin; stop when your show comes back on), lets you rest between sets (while your show is on), and doesn't distract you or anyone else in the room from the program you're watching.