The Mezzalama course crosses above 13,000 feet several times, and at that elevation the temperatures are really cold, even in good conditions. As soon as you notice that you are getting really cold, you should stop and add a layer. The basic rule is simple: You are climbing higher, and therefore the cold is going to get colder. At some point you are going to have to stop and put on something warm so it’s better to do it as soon as you feel cold. This means you don’t tap into your reserves, and your energy is maintained. We were able to overtake other much stronger competitors close to the end of the race because they were freezing cold and had used up much more energy. In summary, maintaining your body temperature sustains your performance. It’s especially important not to arrive at the technical transitions chilled to the bone. If your fingers are frozen, you’re going to have a hard time attaching crampons or putting on your skins.
My product recommendation: I really like the DYNAFIT Borax PrimaLoft Mitts. These mitts are warm, but if you want to get a little cooler, or you need more manual dexterity, it’s easy to slide your fingers through an opening in the palm - meaning, it's not necessary to take off the gloves, which rules out the risk of losing them.