Again, according to Isaac Newton’s Third Law whenever a body exerts a force on another body, the latter exerts a force equal magnitude and opposite direction on the former.
This also means that when your torso’s entire weight is combined with the weight of your thighs, and together this weight pushes down against your seat, your seat pushes back up with an equal force on your posterior and lower back.
One more, instead of having your powerful legs support your body weight, you find yourself in a position where you have to support most of your legs’ weight with a part of your body that already supports your torso’s weight.
This vertical pressure is exerted during the whole time you’re seated in the traditional kayaking position. Furthermore, it is combined with the horizontal pressure that your legs exert on your lower back (see part 1), thus enhancing the ergonomic problem in your lower back.
No wonder cushioned seats and various ‘lumbar support’ solutions don’t change much.
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