I do a full body circuit. NOTE: diet is 70% of training. Eating right helps a lot and you feel better to boot.
--2-3 days at least one day of rest between workouts.
bw squats(slow decent, explosive up)
pushups
bw lunges(slow decent, explosive up)
chinups
shoulder press pushups
dips
reverse crunch(or some sort of core excercise like planks, hanging knee raises)
-- Do this three times
10-15 minutes eliptical
Other than that I stack fire wood, play with my four kids and I walk a lot at work. Important thing is not to forget your core. It will support your upperbody and aid in rotation and gelp balance while carving. For anyone who doesn't like to strength train the old fashioned way. I've had great results with Pilates in the past. It's a great alternative to weight/bodywieight training.
@benttech: I have a weak back as well. If I start to have any back pain at all I start a regemine of bent over barbell rows, pretty heavy, 2-3 sets of 8-10 reps. Always helps. If I had to pick only one excercise to do for the rest of my life... SQUATS!