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MIKE SIMPSON REMEMBERED
I would like to commend Dave Pinel for his heartfelt tribute
to Mike Simpson. I was extremely fortunate to have had
the opportunity to paddle with Mike to the Brooks Peninsula
last summer. He was exactly how Dave described: dedicated,
enthusiastic, supportive, energetic and so much fun to paddle
with. Mike truly was an inspiration.
Sheena Grindlay
THANK YOU!
I just downloaded the Spring 2007 issue of WaveLength, and
felt compelled to write and thank you so much for publishing it,
and making it so accessible. I look forward to every issue, and
find them packed with the most helpful information about paddling.
I’m a 58-year old kayaker who came late to her passion
for kayaking, but the stories you print are often inspirational,
and keep me motivated and keen on improving my skills. Once
again, thank you so very much.
Pam Mayhew
SKILLS FOR A NEW WORLD
Alan, I really enjoyed your “Skills for a New World” in the
spring edition of Wavelength Magazine but—
For all of your preaching about the need for a low impact
ethic to apply to all realms of our life, to which I subscribe,
there are a few facets of your article that I would like to address.
Reality and idealism are not easy bedfellows.
Your boats are, obviously of fibre glass/Kevlar and a polymer
gel construction—all products of the Alberta Tar sands
or other oil producing regions. Would you go back to a cotton
canvas/wood frame boat? Your clothing is oil based nylon/
polypropylene cloth as, probably, is your tent, sleeping bag and
accessories. Back to cotton clothing? Instead of burning wood
from the beach on the campfire, you are, apparently, encouraging
the burning of non-renewable white gas or LPG products.
“Low impact camping?”
Please look through ALL pages of the magazine and you
will see the degree to which we are all dependent on the petrochemical
industry for our “low impact” recreation—especially
the group flying to Tasmania for their kayaking adventure.
I have no answers, I am as guilty as the next “low impact”
kayaker in my use of non-renewable resources, but please remember
“those of us who live in glass houses, should not throw
stones.”
Geoff Russell
Editor’s Note: The Tasmanian paddlers featured in the Spring issue live
in Australia.
FEWER STROKES, FASTER BOATS
I read the article in the spring issue of WaveLength Magazine
and was surprised by some of your ideas. I agree that
varying your cadence on long trips can help to reduce mental
fatigue because paddling for extended periods can be monotonous
and any method of adding variety to your journey can increase
energy levels and overall enjoyment. Moreover, the ability
to paddle efficiently at different cadence levels is important
for your development as a kayaker. There are situations where
paddling at a low cadence (high gear) is necessary, for example
into a stiff headwind. Likewise, the ability to kayak at a high
cadence (low gear) is essential when sprinting against a fast current
to pass through a tidal narrows. However, humans have
anatomical and physiological limitations which affect all aspects
of movement including cadence. As far as I know, “paddling
faster with fewer strokes” can only be achieved in three ways:
developing a more efficient stroke, a more powerful stroke, or
a combination of the two, so the idea that “Gliding...increases
speed” seems suspect. As a kayak glides, it decelerates and loses
kinetic energy. It then takes more work to accelerate the boat
back up to its initial speed. Less power is needed to maintain a
constant velocity than to average the same speed by accelerating
(during a stroke) and then decelerating (while gliding) between
strokes. There is a non linear relationship between speed
and power such that there is a diminishing return of speed as
you apply more power, thus trying to paddle too quickly over
long distances will be inefficient. Therefore, kayaking for long
periods of time, you can emphasize efficiency over speed by using
a lower cadence, a lower stroke angle and a lower average
power output. Taking “micro rests” (gliding) will increase your
endurance in as much as your average power output will be
lower, and hence so will your speed; but this could be achieved
more effectively by simply paddling continuously with slightly
less stroke power. However, there are a few exceptions where
gliding will add to efficiency and endurance: kayaking at very
low power outputs (speeds), say below 2 km/h, while lowering
your paddle onto the deck to rest your muscles between strokes.
Also, when gliding with strong currents, paddling will offer less
advantage.
A kayak does not “glide on its own buoyancy,” nor does
“buoyancy help sustain forward motion,” nor does buoyancy
“increase speed, efficiency and endurance.” In the context of
kayaking, buoyancy is defined as an UPWARD force equal in
magnitude but opposite in direction to the weight of the water
displaced by the kayak. The key point here is that buoyancy
is an upward force, and thus in no way can it add to forward
propulsion. The only way to increase speed is to increase stroke
power or reduce hull drag. Efficiency is increased by improving
paddling form and coordination. Endurance is increased
by high repetition, long duration nonstop paddling training,
emphasizing efficiency.
As for “allowing your kayak to do more of the work,” a kayak
does not do work! A kayak does not produce power, which
is the rate at which work is done. A kayak only produces drag
which acts directly opposite to the power you produce when
you paddle.
Finally, increasing your “gearing” while paddling is not a
function of “putting more oomph (torso rotation) into each
stroke.” One can paddle at an equal speed with a lower cadence
(a higher stroke force) using a longer paddle. I hope this
information sheds light on the subject of stroke cadence and its
relationship to strength, speed, endurance and their combination—power.
Ian Smith
Editor’s Note: Because of space limitations, Ian’s letter was substantially
edited for length. I trust we have retained his key points.
8 WAVELENGTH MAGAZINE SUMMER 2007