This is advice from adventure racing great Roman Dial from Alaska about what to wear when paddling.
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First key concept is that water in your boat chills your legs, not your top.
This means that you might look for high waisted (preferably to the chest) water
protection. In cold water lining your boat bottom with a 3/4 foam pad helps
keep the legs warm.
Second key concept is that feet are the cold temperature sensors, face and
hands the warm temp sensors. This means that if your feet are cold you tend to
chill (and that warming face and hands around fire “warms” body faster). Best
to have some sort of attached sock to the water proof pants above. Ideally,
Alpacka would make us a super light chest high pant with removable socks –
which they did for a year or so. No good for swimming but great for boating up
to Class III with a spray deck. When you walked take off the socks. Consider
some neoprene or goretex fishing chest-waiders; also go with thin neoprene
socks rather than SealSkins.
Third key concept is that water seems to crawl or wick up underneath your rain
jacket, so overdress and wear your foam PFD under your rain jacket.
Fourth key concept is stopping and trying to warm up by walking around seems to
send all the chilled leg blood circulating into your body and you get colder! I
don’t know about Scotland but in Alaska we have willows along rivers for
warming fires, very nice every few hours.
Fifth key concept: Keep water out of your boat! How big is your “big water”? If
you are talking Class III or below, then a spray deck with lots of backpaddling
to maneuver around the big water will help keep you dry. Don’t just power down
the big waves; match your speed to the water so you do not take any on.
