Here's an article I posted in the NSW Sea Kayaker's club magazine last year, reproduced with their permission.
Running on the Sea
Finding the Sweet Spot
I have spent a lot of time over the past couple of years
trying to unlock the mystery of the ‘sweet spot’ of any particular kayak hull.
This is the notion that by tuning in to your particular kayak’s hull shape
& performance, you can maximise your forward speed and efficiency,
expending minimal effort in doing so. It’s essentially to do with a slightly contorted
idea of glide, or the amount of rest you can take between each stroke without
detriment to your overall speed.
I had the concept demonstrated to me in no uncertain terms
by a paddling mate & coach Rob ‘Max’ Walker, on a ski training paddle where
we were trying to ride the stern wake of the Bundeena Ferry. Max had challenged
me to hold onto the fast travelling wake as long as I could, no mean feat
considering it hums along at about 12.5kmh. Hauling myself onto the second of
the three waves that the wake produces I managed to hold position with a little
more effort than normal, and Max then dared me to hop forward onto the steepest
first wave.
I put my head down and paddled for all I was worth, thrashing
around, water splashing everywhere like a Kingfish being hauled onto a tinny, dragging
my bow closer & closer to the elusive sweet spot when the momentum of the
moving water would once again propel me forward without such an effort. In the brouhaha I heard Max’s evil
laugh, and glanced across through the sweat pouring into my eyes to see him cruise
over the lip at half my cadence & output level. ‘You’re hacking’ he barked
at me, ‘let the hull do the work’. I eased off, tried to time my catch &
effort rather than rating through the roof , and sure enough I slipped over the
crest & joined him on the front wave with half the effort I’d been
spluttering out moments earlier.
It was a short & salient lesson, and one that I took
with me on a number of recent long days on the open sea. My motivation for
developing the skill was self-preservation, trying to spare myself undue
physical trauma in undertaking a number of demanding days of open ocean
paddling ranging from 60km up to 117km. The idea that I could pull off a day of
those proportions & back up well enough to do it again the next day was
appealing for a number of reasons, least of all my own safety & the safety
of my paddling mates.
Ostensibly it’s a piece of wizardry you can harness in
following conditions, where the sea presents you with an opportunity to make
ground at speed. Surfing waves on the ocean is to me the greatest joy in our
sport, but not everyone can do it.
Why? Simply, I think as sea kayakers we’re not particularly
tuned in to the idea of running with a sea. Paddlers who make ground
effortlessly in following seas seem to be hardly paddling, just a faster, stronger
stroke every now & then to keep the boat running. The rest of us tend to
stop & start, getting a push from astern as a wave steepens, but then
falling off the back as we either instinctively defend against anything
potentially unpredictable like a broach, or lack the instinct or fitness to get
our sea kayaks running.
We tend make my mistake of lifting our cadence or rating, and
in the maelstrom of thrashing about, stall the momentum of the stroke, and then
go again, over & over on a day’s paddling. Everyone who has paddled in a
following sea & quickly exhausted themselves & reads this should know
exactly what I mean!
To figure out how & when your own boat is inclined to run,
I’d give one simple guide.
Head out onto your local waterway, preferably on a day when
there is a breeze from behind generating enough of a sea to propel you along
once you can hook into the flow. If you have a GPS, stick it on the front deck
and watch your boat speed as you chase the crests of the waves in front of you.
As soon as you feel yourself starting to exceed a comfortable cadence or effort
level, back off and try to keep your speed up by timing everything a little
better. Essentially, try to go just as fast by taking fewer paddle strokes.
My way of achieving this little bit of paddling nirvana is
to visualise the crest of the wave in front of my bow pulling me along, and
then adjusting power & cadence to make sure it stays there. If you drop off
the back, remember there will be another wave along any second, but you’ll use
energy chasing it down & starting again.
When you’re doing it right, you’ll find after a while that
you can bring your effort level (measured properly if you have a GPS with a
heart rate monitor) way down and not lose much at all in boat speed. When these
measurable components start to line up; same speed, less effort, you will be
some way towards working out how & where your hull begins to glide. Another
little factor should also reveal itself if you’re paying attention, the point
at which trying to go faster is a waste of time & effort.
In a perfect world we’d always paddle down sea, so what
value is this idea of run in less favourable or even head-sea conditions?
Again, to put it simply, it gives you a way to work out the point of
diminishing returns, and therefore avoid reaching that extra watt of power that
starts to fatigue you, but doesn’t actually add anything to your boat speed.
Not all boats run the same, but they all do it to some
extent. As an exercise in developing a higher level of paddling efficiency it’s
well worth working out where this sweet spot lurks on your kayak.
Postscript - here's a video of me running a nice little wind driven sea in my ski. The first minute is a reasonable example of what I'm describing above, trying to use the moving water to propel myself along, without using too much effort.
