I also suffered from numb legs and on several occasions literaly 'fell' onto the beach when I exited (most embarrasing). I found that putting some support underneath the lower part of my thighs (close to my knees) helped a great deal. Five or six hours in the kayak is now not a problem.

Dan
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: Can someone confirm my suspicion that the reason my legs go numb after an
: hour or so is because I have made the seat too deep and too close to the
: shape of my backside?
: The seat is ground from closed cell foam and covered with vinyl. It has quite
: a deep concave shape and feels really good and secure for the first half
: hour, but I think the sides press too firmly on the sides of my backside.
: A temporary solution of some extra foam just on the bottom to raise me
: enough to stop this side pressure seems to have solved the problem.
: Is this a recognised problem?