All you skiers, remember. You don’t go skiing to get fit, you get fit to go skiing. Get those legs stronger and fitter. Tired legs lead to faulty technique which can cause injury. I’m getting marathon runners in the clinic now so all you first timers and shorter distance runners remember to hydrate, up your carbs and protein and remember to stretch regularly. Increase mileage sensibly. There are some good marathon training programs on the Internet. Good luck.