The American Chiropractic Association says outdoor activities can cause problems if you aren't in good physical condition, especially if you don't warm up first.
* Skiing: Do 10 to 15 squats with knees aligned over feet, shoulder-width apart. Slowly bend your knees.
* Skating: Do several lunges. Let your back knee come down to the floor if you can, while keeping shoulders over your hips.
*Sledding/tobogganing: Stretching may prevent compression injuries caused by frequent bouncing over snow. Sit or lie down, pull your knees to your chest, and hold 30 seconds.
* Shoveling snow: Not actually a sport, but many people do it for fun or necessity. Do warm-up stretches before you start, especially for your shoulders, upper and lower back, and legs. When shoveling, bend your knees to lift. Let your legs and arms do the work.