**Cotton is a very good material during the summer because it's a material that breads.
    But in the winter it may cause problems, especially if it is worn on top of your skin.
     During your activities, cotton absorbs your sweat and stays wet. 
  So when you stop to take a break and your body relaxes, and cools down you become cold. 
           This is the reason why we recommend wearing wool or synthetic clothing.

It's good to wear layers of clothing. This way, when your body is warm 
 you can remove some layers to avoid getting to wet 
 and when your body cools back down, you can put them back on.
 That way you stay warm all the time.