Originally Posted by
fastk9dad
Originally Posted by
Athens80
Can you explain the difference? I understand that the jersey protects your skin from the direct solar rays. But otherwise it seems like what you want is to get sweat from the skin to the outside of the jersey where air flow will evaporate it. It seems like making the sweat go through the base layer, transfer to and through the jersey, and then evaporate is just going to slow down the evaporation, compared to just wearing a jersey that wicks moisture as well as the base layer material.
There are different types of base layers, most of the ones mentioned in this thread have been the mesh type, which are a little thicker than jersey material but in a very lightweight honey comb type pattern. Sweat is absorbed by the part of the base layer that touches your skin, then is transferred to it's outer edge where it can be absorbed into the jersey to evaporate. The idea is to pull the sweat away from your body and give you a little air gap between the jersey body so the sweat soaked jersey isn't against your body.
I have never had one of these types of base layers sopping wet as described by some, with thinner base layers more like an undershirt, yes and it's sticky uncomfortable, but not the mesh type which I always wear in the summer even with humidity.
+1... The mesh type are very open but have what are probably hollow core yarn that wicks more sweat, thereby increasing the wicking and transportation of sweat from your skin. It also increases the effective surface area available for evaporative cooling, so if you unzip your jersey a little the venting can also allow the baselayer to help cool you off in addition to wicking moisture to the jersey.
You can test this by wearing the thin sun shield style arm sleeves. Cycle in the heat with them on then spray them with water from your water bottle and you'll realize that your arms are actually cooler than if they were just bare skin. Note that the mesh baselayers are basically open like a net so they don't reduce airflow or help to insulate and trap heat.
