High stroke rate inefficient?

[Chilly]

My new favorite quote. 

--"because them's the rules, buckwheat" PonoBill

[upwinder]

Of course it all works in reverse down here in the southern hemisphere.

[upwinder]

No real difference in overall performance because high cadence paddlers need smaller, less efficient paddles. Not a matter of how strong the paddler is. Rod Parmenter is FAR stronger than Devin Blish, but Devin flies with a Molokai and Rod flies with a Wiki. 

This.

The physics is all very interesting but in relation to the OP's question, you're not going to get a universal rule out of it, at least not one that's useful. We and the environments/conditions we paddle in are all too different. I've got a rough idea what works for me on my boards, with my paddles, in my current physical condition, because I've trialled a few things on my favourite courses in my local conditions.

YMMV

[downriver]

I have read all 5 pages of this thread, and I didn't notice much talk about weighting and unweighting the board in relationship to planing. 

If getting your board up on top of the water so that it is planning and keeping it planning longer is the ticket to more overall speed, then looking at the downward push of your paddle in conjunction with bending and unbending your body to change the weight applied to the board, adds another big dynamic element not otherwise covered here. 

When you are heading out through the surf you naturally bend your knees to suck up the wave.  You also plant your paddle as the white wash runs under and drive forward down the backside of the wave as it passes.  These same kinds of motions, when applied to flat water mix up the physics. 

In my 40+ years of alpine snow experience I have learned that the fastest racer uses only as much down pressure on the skis necessary to keep on the fastest line and the skis flat on the snow.  There is a lot of up and down action.

And it is not just up and down on the body weight.  Moving the board in front or behind your balance point, drastically changes the amount of downward force applied to the board at a given moment. 

I once watched a couple of bodyboarders off the Pismo Beach Pier on a day with 15 to 20 foot waves.  (They had jumped off the pier, since no human could swim out through that.)  Right before each wave they would rise up as high as they could out of the water, then sink below the surface, then bobbing back up and forward to catch the wave.


In flat water application it might look something like this. 
1)Begin stroke, body weight goes down and forward to lessen weight on board,    bent paddle pushes down, board goes up.
2)Now that the board is up, the bent shaft is more vertical and pushes more in a forward direction, the board reaches top speed sooner than when using normal stroke.  The hull uses less energy at this speed because it is displacing less water.
3)Pushing down gently increases weight on the now planning hull which, because of the increased speed the hull can support more weight.  Push down by slowly standing straighter. 

Body is now in position to begin next stroke.


all replies welcome, cheers
Marty

http://en.wikipedia.org/wiki/Wave-making_resistance
Another way is to shape the hull so as to generate lift as it moves through the water. Semi-displacement hulls and planing hulls do this, and they are able to break through the hull speed barrier and transition into a realm where drag increases at a much lower rate.