In french, we call this kind of start where you jump in the river "embarquement à l'américaine"... I wonder how you call this in english ?
Seal launch
I'm not a kayaker, but I'm casual American English I've never heard a term for this
"running start" would be the closest thing I could think of in American English, but it's not a perfect match. As it pertains to kayaking, a "running start" would be understood as some sort of momentum transfer while simultaneously hopping into the kayak.
But still, that definition is what a typical American would imagine if you said "kayak running start". So perhaps not totally identical to what I think you're describing.
I haven't heard of a term for that en anglais, but I would call it "scooting in" ou simply just "launching."
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