A wetsuit creates a barrier against the elements
utilizing the insulating properties of closed cell neoprene. Neoprene
is a closed cell foam made up of thousands of tiny air bubbles
known as cells. The air within the cells
creates an insulating barrier which slows down the conduction
of heat and cold and allows body heat to be retained.
The thickness of the neoprene utilized in a wetsuit
will determine its warmth and flexibility.
A thick wetsuit provides a lot of insulation but
can inhibit flexibility. A thin wetsuit such as a 3/2mm wetsuit
will be very flexible but can inhibit insulation.
The key is to get the right combination of warmth
and flexibility so the wetsuit will not only keep you warm, but
provide maximum flexibility as well.
A 'Steamer' is a wetsuit with sealed seams, usually
achieved by blind stitching. This stops the majority of cold water
from re-entering the suit once your body has initially heated
it up. Winter wetsuits are steamers typically
with a 5mm body and legs for warmth and 3mm arms for manoeuvrability.