Thread: Yuloh
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Default Yuloh

Rowing is a much more efficient way to transfer energy to the water from
your muscles. Think for a minute, if that weren't true, we'd have eight
man yuloh sculls.

Tom Best wrote:
I wonder if this is true.


In a while, you'll know firsthand


Sculling off the stern involves primarily
leaning back and forth. Very little muscle activity.


hmm, you must be doing it differently than I always have.

.... Rowing is a much more direct
expenditure of energy for movement but it also involves the recovery
part of the stroke which gives you no return.


True, hadn't thought of that. But it's not a very large percent of the work
done overall (work in terms of FxD).

The reason why I think that rowing is more efficient is that it does not
involve generating lift. Thrust is generated 100% from drag, which is very
easy and also instantaneous. To generate lift over a foil you have to move the
foil at least one chord length so part of each stroke of the yuloh is also
wasted. And you still have to fight drag, but the drag is not helping move the
boat.

So I look at it as this way: for each pound of work expended on the yuloh, X%
is spent generating the lift for that stroke and another Y% is wasted as drag.
With an oar, for each pound of work you get greater than one pound of thrust
because of the leverage, minus Z% for the recovery stroke. So it appears
likely IMHO that X+Y Z. Not very precise math, but so it goes.



On a calories expended per pound of thrust I wonder if rowing is truly
more efficient. Or is it instead just more powerful and fast at the
expense of true efficiency?


That's possible, the leverage is pretty good. And we all know that with a big
enough lever you can move the world.....

Fresh BReezes- Doug King