I'm from the Netherlands and as you might know, we don't have a lot of warm days. Most of the time our days are wet and cold. A surfer then needs a good warming-up so that you don't get to cold in the water. Now i've tried several things (incl. running up and down the beach and a lot of stretching) but several times I feel my neck or arms/legs getting stiff. What do you do as a warming-up? and maybe you have several tips!