Since it is finally starting to feel like winter here in Colorado, I thought I would bring up the topic of skiing and snowboarding. I grew up my entire life on the slopes of the Colorado Rocky Mountains. The funny thing is though, even with all the years that I have spent skiing and snowboarding, I never realized that it was giving me a such a great workout and was not just a source of entertainment. Skiing and snowboarding have secretly been keeping me in good physical condition during the winter without me even realizing it.
I have realized that Skiing and snowboarding do have slight differences in what muscles they help get stronger. For instance, in skiing I feel like it mainly targets my quadriceps and hamstrings for stabilizing and balancing and my abdominals for stabilization as well. In snowboarding (my personal favorite) I feel that I am targeting my shins and my calves more because of the leaning forwards and backwards motion that it requires to steer while also giving me an even greater lower back and abdominal workout than skiing (but that's just my experience).
On top of the muscle strengthening that skiing and snowboarding have given me, they have also been giving me a great cardio workout. Working at being able to balance and control my body while going at a high speed downhill is one of the best (and funnest) ways to keep my heart rate up and burn calories fast. Unlike with muscle strengthening where skiing and snowboarding work different muscles, I have found that both skiing and snowboarding are fairly equal when looking specifically for a cardio workout.
In summary, purely thinking from a fitness point of view (disregarding personal preference (snowboarding)), if I wanted to get a better upper leg workout, I would go with skiing. If I wanted a better core and lower leg workout, I would go with snowboarding.