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From: MATT MARINER BROZE <marinerkayaks_at_msn.com>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 06:12:30 -0700
Niels wrote:

>>>>....I think that covers all objections so far. I'm hoping for more solid
arguments: I was really hoping for a serious discussion on mechanics. I
still MIGHT be wrong, even very wrong; but so far, I have no indication
that I am.<<<<<

Off the cuff, it seems to me that there IS potential energy stored by lifting
the arms but I don't see any advantage to doing that since the paddle is
nowhere near 100% efficient in transferring that energy into forward motion.
Therefore, the more work you put into lifting the paddle the more energy you
waste because of the lack of paddling efficiency gained in return for your
efforts against gravity. If I'm correct about that, then other things being
equal the less you work against gravity during your strokes the more efficient
you should be. This is probably one of the reasons why a bent shaft canoe
stroke is more efficient than a kayak paddle stroke, less energy wasted
lifting the second paddle blade, hand, and arm against gravity and more of
ones effort going to propelling the kayak horizontally through the water.
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 18:12:22 +0200
MATT MARINER BROZE wrote:

 > Off the cuff, it seems to me that there IS potential energy stored by 
lifting
 > the arms but I don't see any advantage to doing that since the paddle is
 > nowhere near 100% efficient in transferring that energy into forward 
motion.
I'm not so sure about that. The mechanics are complicated, but let's 
simply ask: If the energy doesn't transfer to the force and movement of 
the paddle-blade, then where does it go? The movement of the arms is 
nearly frictionless. Nothing heats up, so no energy is lost.
I think almost 100% of the energy transfers to the paddleblade - but 
from there, I have no idea of the efficiency of a blade pushing against 
the water.

 > Therefore, the more work you put into lifting the paddle the more 
energy you
 > waste because of the lack of paddling efficiency gained in return for 
your
 > efforts against gravity. If I'm correct about that, then other things 
being
 > equal the less you work against gravity during your strokes the more 
efficient
 > you should be.
It is indeed possible that a horizontal stroke is more efficient than a 
vertical stroke. The mechanics and physiology are too difficult to put 
in a simple model. The main reason I consider the vertical stroke the 
best, is that it's been taught by most kayak-instructors and used by 
most paddlers. Once they master that stroke, they're able to keep it up 
for hours and stay with the group, so I think there must be something 
good about it.

 > This is probably one of the reasons why a bent shaft canoe
 > stroke is more efficient than a kayak paddle stroke, less energy wasted
 > lifting the second paddle blade, hand, and arm against gravity and 
more of
 > ones effort going to propelling the kayak horizontally through the water.
Efficiency is one thing; being able to keep it up is another. I tried it 
for myself: I can (in my home, with a paddle out of the water) longer 
keep up a forward-stroke motion than a static position. There might be a 
placebo-effect there: I _want_ to be able to keep it up longer.

I don't know if moving an arm uses more energy than keeping an arm 
steady against a force. To a steel crane, it certainly would be, but 
muscles work differently. They're comparable to a car-engine working 
against the clutch, with the car on the handbrake. Lots of energy are 
generated, but none is transferred to forward motion.
There might be a trade-off somewhere: If you move half of the time and 
rest the other half, you might be more efficient than when you keep the 
arm steady, constantly bearing the weight. I don't know.

Perhaps I step too lightly over what the best stroke is. I could change 
it to: "If you teach a vertical stroke, than THIS should be your 
justification".

Thanks for joining the discussion, Matt. I highly value your expertise.
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From: Darryl Johnson <darryl_johnson_at_rogers.com>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 15:40:51 -0400
On 28/04/2011 12:12 PM, Niels Blaauw wrote:
> MATT MARINER BROZE wrote:
>
>  > Off the cuff, it seems to me that there IS potential energy stored
> by lifting
>  > the arms but I don't see any advantage to doing that since the
> paddle is
>  > nowhere near 100% efficient in transferring that energy into
> forward motion.
> I'm not so sure about that. The mechanics are complicated, but let's
> simply ask: If the energy doesn't transfer to the force and movement
> of the paddle-blade, then where does it go? The movement of the arms
> is nearly frictionless. Nothing heats up, so no energy is lost.
> I think almost 100% of the energy transfers to the paddleblade - but
> from there, I have no idea of the efficiency of a blade pushing
> against the water.

I would disagree that "nothing heats up, so no energy is lost". 
Exercise does create heat in the muscles, else there would be no need 
for profuse sweating to cool the body down during strenuous exercise.

But I suspect the amount of energy referred to is small. I doubt you 
could get a kayak to move forward by just using the potential energy 
stored by the effort of lifting the paddle up. Even on a completely 
calm day.

In fact, I suspect this line of reasoning might be accused of counting 
the number of angels to dance on the head of a pin.

My point of view is something like this: the muscles in your shoulders 
(used for lifting the paddle) are weaker than the core muscles used to 
power a forward stroke using rotation. Therefore, one should reduce 
the work done by the shoulders (and arm) muscles to as great an extent 
as possible, and rely instead on the core muscles to do the work of 
moving the boat forward.

You might gain some small advantage by lifting the paddle to a 
slightly greater extent, but I suspect this to be of relatively short 
duration and the advantage would reduce as the shoulder and arm 
muscles tired. During a longer paddle, the gain would be so small as 
to be non-existent.

But I am open to arguments proving me wrong. Lord knows, at my age, I 
can use all the advantages I can get to keep up with my younger 
paddling friends.

-- 
   Darryl


>
>  > Therefore, the more work you put into lifting the paddle the more
> energy you
>  > waste because of the lack of paddling efficiency gained in return
> for your
>  > efforts against gravity. If I'm correct about that, then other
> things being
>  > equal the less you work against gravity during your strokes the
> more efficient
>  > you should be.
> It is indeed possible that a horizontal stroke is more efficient than
> a vertical stroke. The mechanics and physiology are too difficult to
> put in a simple model. The main reason I consider the vertical stroke
> the best, is that it's been taught by most kayak-instructors and used
> by most paddlers. Once they master that stroke, they're able to keep
> it up for hours and stay with the group, so I think there must be
> something good about it.
>
>  > This is probably one of the reasons why a bent shaft canoe
>  > stroke is more efficient than a kayak paddle stroke, less energy
> wasted
>  > lifting the second paddle blade, hand, and arm against gravity and
> more of
>  > ones effort going to propelling the kayak horizontally through the
> water.
> Efficiency is one thing; being able to keep it up is another. I tried
> it for myself: I can (in my home, with a paddle out of the water)
> longer keep up a forward-stroke motion than a static position. There
> might be a placebo-effect there: I _want_ to be able to keep it up
> longer.
>
> I don't know if moving an arm uses more energy than keeping an arm
> steady against a force. To a steel crane, it certainly would be, but
> muscles work differently. They're comparable to a car-engine working
> against the clutch, with the car on the handbrake. Lots of energy are
> generated, but none is transferred to forward motion.
> There might be a trade-off somewhere: If you move half of the time and
> rest the other half, you might be more efficient than when you keep
> the arm steady, constantly bearing the weight. I don't know.
>
> Perhaps I step too lightly over what the best stroke is. I could
> change it to: "If you teach a vertical stroke, than THIS should be
> your justification".
>
> Thanks for joining the discussion, Matt. I highly value your expertise.
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 22:34:55 +0200
Darryl Johnson wrote:

> I would disagree that "nothing heats up, so no energy is lost". Exercise
> does create heat in the muscles, else there would be no need for profuse
> sweating to cool the body down during strenuous exercise.

We were specifically talking about the energy that's lost while 
_relaxing_ the muscles and letting the paddle drop. While your point is 
valid for exercise, it's not for this specific case of rest.
>
> But I suspect the amount of energy referred to is small. I doubt you
> could get a kayak to move forward by just using the potential energy
> stored by the effort of lifting the paddle up. Even on a completely calm
> day.

You must have missed my calculations. In my own stroke, analyzed in my 
own video, I put close to 30 watts into lifting the paddle, while 30 
watts drive a kayak at a speed of 2 kts.
There will be losses, but still: 30 watts is a significant amount of power.

> My point of view is something like this: the muscles in your shoulders
> (used for lifting the paddle) are weaker than the core muscles used to
> power a forward stroke using rotation. Therefore, one should reduce the
> work done by the shoulders (and arm) muscles to as great an extent as
> possible, and rely instead on the core muscles to do the work of moving
> the boat forward.

I addressed this in my video. WHY use big muscles when small muscles can 
do the job? In almost every other activity, we learn to turn to the 
_smaller_ muscles that can do the job, so why not here?
>
> You might gain some small advantage by lifting the paddle to a slightly
> greater extent, but I suspect this to be of relatively short duration
> and the advantage would reduce as the shoulder and arm muscles tired.
> During a longer paddle, the gain would be so small as to be non-existent.

If you look at my stroke in the video, you'll notice that I have a 
pretty average forward stroke. (It's at 7.50 minutes, and for your 
convenience, here's the link once again: 
http://www.youtube.com/watch?v=-aB0rdn4UnQ ) I'm not promoting a new 
stroke; I'm not urging you to raise the paddle higher. I'm just asking: 
Why DO we raise the paddle that high?
>
> But I am open to arguments proving me wrong. Lord knows, at my age, I
> can use all the advantages I can get to keep up with my younger paddling
> friends.
>
Why not try? Paddle your boat into the dock, see if you can find the 
vertical rest, and see if you can put it to use.

Niels
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From: Mark Sanders <marksanders_at_sandmarks.net>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 14:11:32 -0700
I can accept that potential energy contributes to the stroke, but are 
you saying it's the prime mover? I wish I was on the water right now to 
give it a test. It seems even at 2kts, there has to be some more energy 
involved.

Mark Sanders

On 4/28/2011 1:34 PM, Niels Blaauw wrote:
>> But I suspect the amount of energy referred to is small. I doubt you
>> could get a kayak to move forward by just using the potential energy
>> stored by the effort of lifting the paddle up. Even on a completely calm
>> day.
>
> You must have missed my calculations. In my own stroke, analyzed in my 
> own video, I put close to 30 watts into lifting the paddle, while 30 
> watts drive a kayak at a speed of 2 kts.
> There will be losses, but still: 30 watts is a significant amount of 
> power. 
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 23:33:59 +0200
Mark Sanders wrote:
> I can accept that potential energy contributes to the stroke, but are
> you saying it's the prime mover?

I wouldn't dare! Although I say it generates 30 watts, and 30 watts is 
what's required to get that speed (from some table I linked to earlier) 
there are losses involved that I don't account for. I think the 
vertical-rest-stroke might account for about 50% of the force in my own 
stroke - but even if it were just 25%, it would still be significant, 
especially since it's for free. You lift your arms anyway, so you might 
as well put that energy to some good use by relaxing your arms.
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 23:53:07 +0200
Mark Sanders wrote:
> I can accept that potential energy contributes to the stroke, but are
> you saying it's the prime mover? I wish I was on the water right now to
> give it a test. It seems even at 2kts, there has to be some more energy
> involved.

Something else that is easily forgotten: 30 watts is nothing when it 
comes out of the socket, but it's quite something when you have to 
produce it yourself. We're extremely spoiled with our x1000 watts 
washing machines, heaters, vacuumcleaners, powerdrills and cars. I 
hardly remember the last time I turned a screw by hand.

 From wikipedia (lacking a better source)
http://en.wikipedia.org/wiki/Human-powered_transport
 > In lab experiments an average "in-shape" cyclist can produce about 3 
 > watts/kg for more than an hour (e.g., around 200 watts for a 70 kg
 > rider), with top amateurs producing 5 watts/kg and elite athletes
 > achieving 6 watts/kg for similar lengths of time.

I think kayaking is much less efficient than cycling; we can keep it up 
for longer than an hour. I'd be surprised if we produced over 75 watts 
of useful energy - which again makes 30 watts quite significant.
(The number 75 is from another, even less reliable source. Never trust 
fundamental greenies. Still: It's a nice number to quote.)

Niels
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From: Craig Jungers <crjungers_at_gmail.com>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 15:13:21 -0700
On Thu, Apr 28, 2011 at 2:53 PM, Niels Blaauw <niels_at_nibla.nl> wrote:

>
>
> ...I think kayaking is much less efficient than cycling;...
>

At least two decades ago Scientific American stated that the most efficient
machine in the world was a fully loaded 747 jet airliner at 35000 feet (in
terms of passenger miles versus BTUs burned).

The second most efficient was a bicycle. :)

I'm sure that airliners have become even more efficient with modern engines
but the bicycle is probably right up there, still.

Even so a kayak is very easy to propel at very slow speeds. I would imagine
10 watts would get a kayak to 1mph with no trouble (in no wind).  I'd bet
Matt Broze has some data on this somewhere.

Craig Jungers
Moses Lake, WA
www.nwkayaking.net & www.bigboxbikes.com
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Fri, 29 Apr 2011 01:42:33 +0200
Craig Jungers wrote:

> Even so a kayak is very easy to propel at very slow speeds. I would
> imagine 10 watts would get a kayak to 1mph with no trouble (in no
> wind).  I'd bet Matt Broze has some data on this somewhere.

Intriguing! In fact interesting enough to go to my kayak upstairs and do 
some measurements:
- If I sit down and stretch out my paddle, to where I would usually put 
it in the water, it's 1.20 meters front of my backrest. Supposing I end 
my "power" phase where it should, at my hips, I move the paddle through 
the water for 1.20 meters, from my own perspective.
- If I put my paddle in various positions, with the blade against a 
scale, I hardly can push it above 5 kilograms. I'd guess my average 
force on the paddle is about 3, during normal touring.
- A stroke on one side takes about 1 second. (A full cycle, left and 
right, will take twice that long. Whenever I talk about a stroke, I mean 
one slash on just one side.)

 From there, it's the most basic physics in the world: Force * distance 
= energy. energy/time = wattage. These are actual _definitions_: Energy 
is measured in Nm, which means Newtons per Meter. Wattage is defined as 
Nm per second.

Anyway:

- Distance: 1.20 meters
- Force: 30 Newton (amounts to 3 kg)
- Time: 1 second
===================
- Output: 1.2*30*1 = 36 Watt. Let's say between 30 and 50.


In a full sprint, I could perhaps raise the force to 60 Newton and do it 
in half a second, creating a burst of 144 watts (let's say between 100 
and 200) - for about 10 strokes, perhaps.

---------------

Now for the efficiency. I rechecked the 'net for drag tables:
http://www.cyberiad.net/library/kayaks/skmag/skmag.htm
http://www.keelhauler.org/khcc/seakayak.htm
http://www.oneoceankayaks.com/kayakpro/kayakgrid.htm

...and found that they quite consistently measure 1.9 to 2.1 lbf to get 
a seakayak to a speed of 3 kts, which is my touring speed. That's about 
1kg or 10Newton. The distance over 1 second (calculated from the 3-knot 
speed) is 1.5. Again: Wattage = distance*force/time = 15 watts. FIFTEEN 
WATTS! What's happening to my other 15!?

Well: I have a much slower boat than listed in any of these tables. 
Efficiency might be as low as 50%, or as high as 99%. Let's hope Matt 
has more accurate data on paddle efficiency.

Time to walk to dog. No one can say that "I should get out more".

Niels
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From: PeterO <rebyl_kayak_at_energysustained.com>
subject: RE: [Paddlewise] A new way to teach the forward stroke?
Date: Fri, 29 Apr 2011 19:08:25 +1000
G'day,

There's an interesting chapter on human power in Wilson's classic book
'Bicycling Science' that covers the human power generation and energy
consumption for movements such as cycling and rowing. On the whole the two
seem to be comparable despite the very different actions. On a bike 100W
seems to be a reasonable cruising power and 200W a decent workout over an
hour.

Re the horizontal vs. vertical stroke some considerations on classic body
types that fit a large proportion of older paddlers:
	the increased efficiency of a 'horizontal' paddle stroke if the
paddler has restricted mobility and relatively high upper body strength
compared to abdominal muscle strength 
	the increased efficiency of a 'vertical' paddle stroke if the
paddler is flexible with low upper body strength but strong abs.

Grand discussion Niels and Matt. Thanks. I'm about to cycle home!

All the best, PeterO
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From: Richard Culpeper <culpeper_at_tbaytel.net>
subject: RE: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 20:03:56 -0400
The most relaxed forward stroke is the Ottawa Shuffle.

Lie back, all the way back on to the rear deck.  Let your hand rest on your
chest, where they hold the shaft of the paddle.  Paddle by alternately
cocking the wrist and raising the fingers of one hand, and then cock the
wrist and raise the fingers of the other hand.  Enjoy, but try not to doze
off.
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Fri, 29 Apr 2011 02:31:27 +0200
Richard Culpeper wrote:
> The most relaxed forward stroke is the Ottawa Shuffle.
>
> Lie back, all the way back on to the rear deck.  Let your hand rest on your
> chest, where they hold the shaft of the paddle.  Paddle by alternately
> cocking the wrist and raising the fingers of one hand, and then cock the
> wrist and raise the fingers of the other hand.  Enjoy, but try not to doze
> off.

I've seen that stroke many times, usually performed by a girl in the 
front of a double rental.

I never knew it had a name though. Possibly the Dutch don't dare mention 
it, referring to it as the "you-know-what" stroke.

Myself, I've found a way of cruising with the wind, sticking my paddle 
under a deckline, using it as a rudder by rotating it with one hand. It 
allows me to put my feet on deck (toes in the water, temperature 
permitting) and leaves the other hand free to smoke, take pictures and 
play with my GPS.
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From: Mark Sanders <marksanders_at_sandmarks.net>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 14:36:25 -0700
I thought you're model was a good way to show that PE can propel a 
kayak, but I don't think it mimics true paddle mechanics of the human 
very well. If you're putting in 30 watts to raise your paddle, I would 
think only a fraction of that would find itself going to forward motion.

Mark

On 4/28/2011 1:34 PM, Niels Blaauw wrote:
> You must have missed my calculations. In my own stroke, analyzed in my 
> own video, I put close to 30 watts into lifting the paddle, while 30 
> watts drive a kayak at a speed of 2 kts.
> There will be losses, but still: 30 watts is a significant amount of 
> power. 
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From: Darryl Johnson <darryl_johnson_at_rogers.com>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 18:00:27 -0400
On 28/04/2011 4:34 PM, Niels Blaauw wrote:
> Darryl Johnson wrote:
>
>> I would disagree that "nothing heats up, so no energy is lost".
>> Exercise
>> does create heat in the muscles, else there would be no need for
>> profuse
>> sweating to cool the body down during strenuous exercise.
>
> We were specifically talking about the energy that's lost while
> _relaxing_ the muscles and letting the paddle drop. While your point
> is valid for exercise, it's not for this specific case of rest.
>>
>> But I suspect the amount of energy referred to is small. I doubt you
>> could get a kayak to move forward by just using the potential energy
>> stored by the effort of lifting the paddle up. Even on a completely
>> calm
>> day.
>
> You must have missed my calculations. In my own stroke, analyzed in my
> own video, I put close to 30 watts into lifting the paddle, while 30
> watts drive a kayak at a speed of 2 kts.
> There will be losses, but still: 30 watts is a significant amount of
> power.

I am not a physicist, and, yes, I did skim over your calculations, so 
I may have missed an important point. But from empirical observation, 
I can't believe that you gain enough energy to move a kayak simply by 
letting the weight of arms and paddle fall. In my own test -- sitting 
on a stool and going through the paddling motion, I'd estimate that 
most of the motion of the paddle blade is downward, with only a small 
amount going back as my shoulder joint forces the arm backward as it 
nears the bottom of the "fall".
>
>> My point of view is something like this: the muscles in your shoulders
>> (used for lifting the paddle) are weaker than the core muscles used to
>> power a forward stroke using rotation. Therefore, one should reduce the
>> work done by the shoulders (and arm) muscles to as great an extent as
>> possible, and rely instead on the core muscles to do the work of moving
>> the boat forward.
>
> I addressed this in my video. WHY use big muscles when small muscles
> can do the job? In almost every other activity, we learn to turn to
> the _smaller_ muscles that can do the job, so why not here?

I don't buy your argument from the video. Yes, we use small muscles to 
scratch our heads. They have the more delicate control needed to hit 
the itchy spot. But scratching doesn't require much force. If more 
force was needed, we'd use larger muscles. If force and endurance are 
needed, your fingers, or even your arms, aren't going to make the grade.

If you carve a chicken or turkey for Sunday dinner, you will note 
there is so-called "white meat" and "dark meat". The white meat is on 
the breast: these are the muscles that power the wings for flying (in 
pre-domestication days). The dark meat is the muscles that are used 
for shorted spurts. Your arms are dark meat. They're fine for shorter 
bursts of energy, but they tire after a while. Your core muscles (not 
just the back muscles, by the way) are more like the white meat. 
They're designed for continuous use over longer periods -- like a 
day's paddle.

>>
>> You might gain some small advantage by lifting the paddle to a slightly
>> greater extent, but I suspect this to be of relatively short duration
>> and the advantage would reduce as the shoulder and arm muscles tired.
>> During a longer paddle, the gain would be so small as to be
>> non-existent.
>
> If you look at my stroke in the video, you'll notice that I have a
> pretty average forward stroke. (It's at 7.50 minutes, and for your
> convenience, here's the link once again:
> http://www.youtube.com/watch?v=-aB0rdn4UnQ ) I'm not promoting a new
> stroke; I'm not urging you to raise the paddle higher. I'm just
> asking: Why DO we raise the paddle that high?
>>
>> But I am open to arguments proving me wrong. Lord knows, at my age, I
>> can use all the advantages I can get to keep up with my younger
>> paddling
>> friends.
>>
> Why not try? Paddle your boat into the dock, see if you can find the
> vertical rest, and see if you can put it to use.
>
I may certainly do that, once I get my boat back on the water. Again, 
as others have said, it's an interesting point of discussion.

-- 
   Darryl

> Niels
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From: Niels Blaauw <niels_at_nibla.nl>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Fri, 29 Apr 2011 02:11:26 +0200
Darryl Johnson wrote:

> I can't believe that you gain enough energy to move a kayak simply by
> letting the weight of arms and paddle fall.

I've learned not to challenge beliefs. Challenge my facts, observations 
and measurements with counter-facts, observations, measurement or logic, 
and I'm all yours.
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From: Robert Livingston <bearboat2_at_comcast.net>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 20:15:00 -0700
When I eat, I lift my fork countless times. How come I am just getting  
fat and not going anywhere?
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From: Bradford R. Crain <crainb_at_pdx.edu>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 21:32:31 -0700
Bob, what are you eating? And drinking?
-- 
Bradford R. Crain

Quoting Robert Livingston <bearboat2_at_comcast.net>:

> When I eat, I lift my fork countless times. How come I am just  
> getting fat and not going anywhere?
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From: Craig Jungers <crjungers_at_gmail.com>
subject: Re: [Paddlewise] A new way to teach the forward stroke?
Date: Thu, 28 Apr 2011 21:36:19 -0700
On Thu, Apr 28, 2011 at 8:15 PM, Robert Livingston <bearboat2_at_comcast.net>wrote:

> When I eat, I lift my fork countless times. How come I am just getting fat
> and not going anywhere?
>
> You obviously need a heavier fork. Try putting more food on it.

Craig :)
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