I know that the guys who work out a lot will get a good laugh out of this but heavy hands walking works amazingly well for stamina and cardio. My routine consists of 32 minutes per day, five days per week on a treadmill at 60 - 75% of MHR doing various exercises with hand weights (have built up to 5 lb weights now). I am still heavy for my height (5'8" 185 lbs) but it has allowed me to get in many more passes even at the slower speeds that I ski. At 40 years old, I am in as good cardio condition as I have ever been, and there was a day that I was at 150 lbs and could crank 50+ pull ups consecutively (the good ole college days). If interested shoot me a PM and I'll let you know more about my routine. Its all I do, nothing else. I went from 205 in March to 185 now with heavy hands and a proper diet (tried Insanity and all that crap but it does me more harm than good). Plan to drop to 165.
What I most like about heavy hands walking is its effectiveness, convenience, and the fact that it doesn't drain you, I can ski immediately after I'm done. I don't dread it. It is something that I can maintain for the rest of my life. Heck, I get out of bed and go straight to the treadmill, and I've gone for 15 minutes before I even wake up:)