...mmmm. obviously those assumptions are pretty debateable duck without some pretty detailed scientific testing.... but i do agree you have to have a well-fitting fin.

then again, take the ala foot pocket for example.... not 100% perfect but a size 42-44 fin will fit pretty perfectly to a size 11-12 (US) foot, in particular around and under the ankles etc and the arch of the foot... cos its nice and stretchy i guess. there might be a few mm of movement around the toes but pretty darned minimal, and if you follow ducks logic of movement with no contact equalling waste then its only a fraction of a second of waste at the very start of any stroke, such a tiny fraction as to be almost irrelevant.

i guess what i'm trying to say is, alas, leaders etc have shown that its possible to get a very good fit with a mass produced design (of course could be improved still further...)

...so possibly the added complications, time, effort and cost of custom fitting fins to a particular foot would outweigh the possible improvements gained in any performance boost.

but then again i guess it has to be done first to see what advantages it would have!


also just thinking aloud but wouldn't there be problems with the change of the shape of the foot between extended, pointed through the down stroke and say, fully flexed and drawn up as the foot would be while sitting stationary on the bottom, or through turns? surely the foot would change shape as its extended and compressed, as force is driven through it in the same way a runners foot flattens and expands on inpact with the ground.... and we're restricted to tougher material than can be used in running shoes. that skin has to be able to wrinkle or go somewhere surely... maybe you'll have to use a very flexible material otherwise the foot will be locked into a position that is great when swimming but uncomfortable while static or turning?

what do you reckon fk pk?

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