More Efficient Paddling

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P1 BLADE, BODY, BOAT The Physics of Paddling I March 11 /July 14 1

Blade [the paddle in water]

Paddlers transmit body power through the paddle blade to move their boat. As positive pressure is generated on the powerface, partial vacuum is created on the backface, the differential forces, called thrust, drawing paddle, paddler and hull through the water

Trial and error by marathon, sprint and whitewater racers indicates 8.5” +/- .25” is the optimal paddle blade width. Wider requires more reach to work over the canoe side, narrower doesn’t hold enough pressure.

Blades need to be shaped with relieved shoulders to work under the hull and rounded tips to allow less than perfect catches as the blade is inserted for each stroke. Reinforcing ribs should be faired into the paddle faces; straights requiring balanced camber on power and back faces to slice accurately. Bents are seldom sliced due to lower stance in the boat and shorter shafts, and do not require face camber.

The paddle blade is an inefficient propulsion device. It provides cyclical power in pulses and it can lose purchase by fluttering, allowing water to stream off its surface and by ventilating, sucking air down its backface to compromise thrust. Attention to the neck, where blade and shaft meet and shaft length will reduce ventilation.

As J Winters proved in ~1990, paddles are most effective when +/- 10 degrees of square to the stroke and significantly less effective at angles much beyond the +/- 10 dg “Winters Window.” The rowing/sculling community selects 20 dg. Averaging those numbers leaves us at a +/- 15 degree window. Functional paddlestrokes are always shorter than commonly performed. Carrying the paddle aft of the body and past the “Winter’s window” compromises efficiency as well as adversely affecting a hulls direction. Art/Pic 1

The paddle is most efficient and predictable in powering paddlecraft when the shaft is either vertical for forward, back, and abeam strokes or horizontal for sweeps and reverse sweeps. A vertical paddleshaft requires that the paddlers grip or top hand be outside the hulls’ maximum beam at the paddler’s station. Stacking our hands, the top hand directly above the shaft hand, requires significant torso rotation, more than most of us commonly use. Positioning the top hand inside the rail introduces a horizontal component, transforming forward strokes into sweeps that turn the boat. Similarly, carrying the blade aft of the body rsults in sweeping force that turns the boat away from paddleside. Art/ Pic 2

The stroke itself must be parallel to the hulls keel, not its rail. Paddling along the rails, in bow, center or stern paddling stations adds a sweeping component to forward strokes forcing the hull into yaw and turning the craft off course. Art / Pic 3

Paddle selection; Straight or bent, determines where the +/- “Winter’s window” occurs in any given stroke and when the stroke becomes ineffective and should be recovered to a successive stroke. With straight paddles square to the “window” forward of a kneeling paddler’s knee, and end just aft of it for sitters. Bent paddles square to the window from the sitting paddler’s knee to mid thigh. Bends are usually 12 dg after decades of experimentation; close to the “windows” edge for draws and pries. Tripping paddlers carry bent and straight for fatigue relief. Art/ Pic 4 The bent being used to change range of muscle motion and when higher cadence usefully improves speed. The straights 2 usually employed when maneuvering is important.

The paddlers hold on the paddle is also key; both hands should be loose. A loose shaft hand allows significant forward extension of the catch. Comparing loose lower grip with a shaft hand death grips suggest invcreased forward placement of the catch by almost a foot. Similarly, tight top hands reduce the paddler’s ability to pitch the blade.


Body [bio-mechanics / the paddler in the boat]

Paddlers should use large muscles to increase power and endurance, specifically the Latissimus dorsi, Posterior Deltoid, Triceps, Teres, Trapezius, Rhomboid, and the longitudinal spinal muscles loosely grouped as the ribeye.

To utilize these muscle groups that are mostly in the back, paddlers should use their arms as struts, locking them in a partially bent position. Torso rotation engages the back muscles in powering the stroke, and increasing forwards reach to the catch.

Paddler stance in the boat can enhance or compromise biomechanical output. Standing
or high kneeling engages the leg muscles, provides the greatest range of motion and
keeps the paddleblade square to the stroke longer. They are also the least stable stances in the boat, with elevated Center of Gravity, [CG]. Bone to boat contact is
through knee and foot or feet.

Kneeling with the knees in the chines and butt on a seat provides a more stable stance with CG well inside hull and still engages the legs to power forward strokes and improve both rotation and forward reach. Both knees provide bone to boat contact, transferring power from the body to the boat and also improving stability. The straight blade paddles’ Forward Stroke squares into the “15 Degree window” completely forward of the knee. Kneeling with a bent is more restful than using a straight because forward reach is reduced, and speed increases with the higher cadence the shortened reach and shaft allows, but directional control is compromised with the bent because the power pulse is further aft along the hull and thumbs down correction is less effective with bent blades because they are often outside the “Winters window” by design.

Sitting reduces torso rotation, reach and stability. The paddler rotates from the seat up while balancing on narrowly spaced sitz bones. While CG is lower, the bone spread increases the rate of roll so stability is lessened. A footrest or foot pegs are needed to provide bone to boat contact for balance and force transfer.

The reduction in rotation means that sitting paddlers are unable to reach far enough forward to square straight blade paddles to the stroke. The use of bents, which square into the “window” alongside the paddler’s thigh, are more efficient than straight blades for sitting paddlers. Shortened rotation and reach can yield higher cadence and thereby higher fprward speed. The reduced effectiveness of the bent’s thumb down correction also encourages higher cadence and switching sides to control yaw. Higher cadences tend to require smaller paddleblades for speed through the water and to reduce injury.

Recoveries need to be horizontal and feathered, the blade carried forward to catch position with ample torso rotation and relatively stiff arms. In-water recoveries increase drag, slow cadence and may misdirect the hull.

3
The relaxed, reclining, position assumed as paddlers lean into backrests compromises rotation, reach, power and directional control, but is appropriate for birding, fishing, photography and reading.


Boat [the hull in water]

A quiet boat is an efficient boat. Yawing off course, sideways roll, and fore to aft pitching all disrupt smooth water flow along the hull, increase drag and slow the canoe.

Biomechanics may need to be compromised to keep the hull quiet; specifically lunging to an extremely forward catch and allowing a longer forward stroke may cyclically pitch the hull bow down, causing drag through disruption of waterflow along the hull. Over reaching over a wide hull’s side to present a vertical paddleshaft may start cyclical side to side rolling, that will disrupt smooth waterflow along the hull, slowing the boat and decreasing stability. Failing to keep cadence will induce rolling and yaw. It is better to miss the top grip and complete the next stroke with top hand on the shaft than disrupt cadence. Yawing off course increases hull crab and tends to skid the stern, bot disrupting smooth flow along the hull.

Hulls can be heeled to one side or the other to lift the stems and increase rocker, tightening turns. Pitching the hull bow down for forward turns further increases skid rate. Heeling and pitching upright helps stop rotation, but all these movements must be smooth to minimize waterflow disruption over the hull surface.

All this suggests shorter forward strokes within John Winters Window for SUP Boards, Canoes and Kayaks. Cadence destroying Corrective Maneuvers especially the J Stroke, should be minimized and switching sides, or cross forward strokes for kneeling soloists, is the preferred method of course correction, with the knowledge that such need indicates Forward Stroke problems. Wind, Waves? pick up cadence and speed to, stuff/pin the bow in the water. The stern generally follows.

Attention to the Paddleblade Physics, Bio-Mechanics and the Boat in the water allow us to paddle more efficiently, farther and faster with less effort. Not a bad idea as few of us are getting younger.

[There is More.]

© Charlie Wilson
 
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Glenn MacGrady

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Very nicely done, as expected. In the spirit of a dialog to advance technical understanding, I'd like to quibble with a few points.

As J Winters proved in ~1990, paddles are most effective when +/- 10 degrees of square to the stroke and significantly less effective at angles much beyond the +/- 10 dg “Winters Window.”

Winters didn't really discover or prove anything. It's self-evident that propulsive power is maximal when the paddle blade is 90 degrees flush to the water and non-existent when the paddle is at 0 degrees. The propulsive power obviously slopes off, probably in a curve, between 90 and 0 degrees. Whether an efficient stroke length "window" should be 20, 30, 40 or some other amount of degrees, depends somewhat on the type of paddle, length of paddle, size of the paddler, size of boat and type of stroke. I agree with the underlying general point that many paddlers take too long a stroke, and like your practical advice relating the length of the stroke to the paddler's knees, thighs and hips more so than the theoretical construct of a fixed geometric window.

The paddle is most efficient and predictable in powering paddlecraft when the shaft is . . . vertical for forward . . . strokes

Every expert says this, but I think it's the most practically misleading and incorrect "rule" of paddling in the literature.

I don't disagree with the idealized efficiency physics of a vertical paddle drawn parallel to the keel. That is the ideal way to minimize yaw. However, holding a paddle vertical with the grip hand outside the gunwale is not efficient in practice for most paddlers because: (1) the boat may be too wide (as you correctly point out later in the article); (2) the boat may be too deep (such as a whitewater or deep tripping hull); and/or (3) the paddler's torso and arms may be too short to reach the grip hand over the gunwale without inefficient body contortions (as will be true for all but the very tallest paddlers).

Studying film of top marathon, whitewater and outrigger canoe racers will show that none of these experts hold the paddle vertical when the hull is level (unheeled). They all hold the paddle at what I call a "comfort angle" with the grip hand inside the gunwales, the precise angle depending largely on their torso and arm size. The key point for practical efficiency physics is not the having of a vertical shaft, but rather the having of paddle face that is 90 degrees flush to the line of the stroke draw.

Imagine a big flat clock face in front of the paddler. The paddle starts out flush and flat against the plane of the clock face. The paddler should draw his stroke in a line parallel to the keel to minimize yaw, as you point out. To do this, the paddle shaft does not have to be pointed at 12 o'clock. The paddle can be drawn parallel to the keel when the shaft is pointing at 11 or 10 o'clock, so long as the face of the paddle is kept 90 degrees flush to line of the draw (i.e., kept in the same plane as the face of the clock). With the paddle at an efficient "comfort angle", this kind of stroke can quickly peter out into a sweep at the end. That's another reason to finish the stroke quickly, as advised.

Sitting . . . . While CG is lower

If the seat height remains the same, sitting will raise the CG vs. kneeling. You must be implicitly assuming here that the sitting boat has a lower seat than the kneeling boat.

Cadence destroying Corrective Maneuvers especially the J Stroke, should be minimized and switching sides or cross forward strokes are the preferred method of course correction

I'm completely puzzled by the recommendation of a cross forward as a regular correction stroke.

If one is a racer or otherwise concerned with maximal speed, switching is the most efficient stroke. No competent switcher is ever going to do a cross forward stroke, especially with a bent shaft paddle.

Nor is it efficient to alternate forwards and cross-forward strokes with straight paddles except for short bursts. It takes a lot of energy and is slow.

A single-sided correction paddler has to correct for yaw in some manner. The regular use of cross forward strokes in the off-side bow is much less efficient than using a traditional correction in the on-side stern, such as the J, C, pitch or Canadian strokes.

Cross forward strokes have many important uses in canoeing. I consider them a sine qua non for intermediate level whitewater paddling. However, I simply disagree with any claim that they can be an efficient method of regular correction for a flat water forward stroke. (If you have in mind their use as a correction mechanism while engaging in the so-called "inside circle forward stroke", I suggest that is a niche and debatable topic.)
 
G

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Speaking on the topic of biomechanics, I often notice myself tiring (or rather getting sore) in the upper trapezius muscles.

That could just be a function of my muscle mass and build, but what does this indicate in terms of stroke form?

I have to admit I'm very unstudied on biomechanics...
 
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Speaking on the topic of biomechanics, I often notice myself tiring (or rather getting sore) in the upper trapezius muscles.

That could just be a function of my muscle mass and build, but what does this indicate in terms of stroke form?

I have to admit I'm very unstudied on biomechanics...

Without seeing you in person, all I can do is throw out possibilities.
1. Your paddle is too long. At some point you are lifting your grip hand over your nose
2. Your recovery is too high.. It should barely clear the water, feathered.
3. You aren't using enough abdominal muscles for power, but rather too much arm. An exercise is to imagine holding a beach ball or basketball by your elbows in front of you and paddle. This forces you to use your abdominal muscles. Don't worry.. no one paddles like this for long but if you can improve the use of core muscles it takes a lot of pressure off the trapezius. Also this forces you to use a vertical paddle plant.. The ideal in theory may be as Charlie presents but reality is more like Glenn presents. There is merit in taking both to thought.
 
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Glenn offers several points of constructive criticism.

I should make my annual mention that every interested paddler needs acquire John Winters "Shape of the Canoe", now available as a download. He has condensed several books worth of hydrodynamic knowledge into one small work, and saves us a bunch of purchases and flipping past chapters on salt water electronics. His paddle experiments are included.

I've made some assumptions that are exclusionary, among them that if a boat is too wide for the paddler to allow stacking his hands he'll find one that isn't. The goal of a vertical paddleshaft is often not achieved, and it requires more torso rotation than many of us use. But our boats behave better with the top hand stacked over the shaft hand, the closer to that goal the better.

Similarly, I assume that dedicated sit down paddlers will acquire sit down boats like a Grass River, Savage River, Sawyer or Wenonah; the seats generally being fist and thumb, about 5", off the hull. Kneeling paddlers usually have their seats ~9" off the bottom in Bells, Coldens, Mad Rivers and NorthStars. Those are not universal truths. but most who are focusing on better technique will get in proper bottoms that fit them and are designed for their chosen paddling style. Those who don't care probably aren't reading this.

And, Glenn is correct about that Cross Forward correction. It works fine for kneeling solo paddlers with a straight blade and is faster than switching sides, but everyone else it is worthless, Solo sitters and tandem teams, are way better switching.

So I've edited the piece to reflect Glenn's suggestions.
 
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G

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Back to the biomechanics:

1 - I get the stress/strain in the same area regardless of paddle length.
2 - I often Canadian stroke with the blade horizontal in the water upon recovery and when correction not needed, just about the water. This is newer since soloing, and soreness is less.
3 - Most likely. My core is weak, and I often sit 'Indian style' and not with my feet forward in the tandem. I know this is poor form but it is comfortable for the long haul.

Soreness has been less since xc skiing again. I think poling has toughened up that area over the winter.
 
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Don't forget to relax your power muscles during the paddle recovery phase. On long marathon canoe races, mastering this relaxation is necessary to allow paddling all day long at race pace and to prevent total muscle fatigue. Just that half second (or less) that it takes to swing the paddle on the recovery is enough if you learn how to completely relax, in preparation for the next catch and burst of power. It works at recreational pace as well.
 
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You can keep the Cab... bleh... I'm strictly Finger Lakes white only... or beer.
 
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Well, Dear l"o;

The trail to good, mouth filling red's can be circuitious but we need to get started; way more important than this paddling stuff. Start with a RavensWood Merlot, the higher priced the better. After your week of joy we'll take the big step to Zinfandel!
 
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This thread has been the most useful on the forum for me to date.

Thanks to all :- )

To this point of my canoe 'career' I've been about a 75%/25%, moving-white water to flat water paddler.

Since we moved to AZ I paddle way more flat water between river trips. That's the nature of SW canoe tripping for me. But I've, maybe stubbornly :- ) refused to adapt my style, boat and paddle to flatwater.

The point is, all this flat water paddling and attention to it has really tightened up my boat control and river game. I think I was accepting/not recognizing sloppy paddling because of the white water aspect.

I do 'cheat' a little haha my canoe is a Supernova and I take a 6 gal water can and fill it with lake water to simulate my loaded Granite Gear 'Traditional' pack. Sliding it back and forth to adjust trim, like I do my pack.

I might be the only Supernova owner on the planet that hasn't moved the seat :- ) I like it where they put it when I'm at trip weight on a class II-III river (sometimes more when the rain gods smile a week into a two week trip).

I kneel 80% of the time adjusting the weight on my knees by how far I slide up on the seat.

...anyway I'm starting to ramble and just wanted to say I appreciate the finer aspects of things these days :- )
 
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Thanks Charlie. I have no disagreement with the physics of this description. I learned some valuable theoretical stuff from Ray H. at freestyle symposiums. One of the things that amazed me was his taking his paddle out of the water, and going straight forever with no corrective stroke forever. Unfortunately, my canoe is propelled by an aging creation with physical limitations, not a machine. I try to keep the hydraulic facts in mind, while adapting my stroke as best I can. Also, some things are just plain more pleasurable, but not ultimately the most efficient.
Turtle
 
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I find this analysis of paddling, by way of the scientific disciplines of biomechanics and kinesiology, under the overarching umbrella of physics, quite interesting. It will be helpful to some. However, the essence of paddling (for the most of us who do it for fun) is found in aesthetics i.e. beauty and spirit. To that end I have two simple contributions to the thread: 1) Physicists theorize that the smallest of universal particulate movement (and therefore all movement) can best be described as "spirit". And that is a beautiful notion. 2) Indeed, maybe the ones who invented the canoe, and understood it as a function of the Great Spirit were onto something.
 
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But the beauty is in that area of the Venn diagram where physics meets spirit and the music of the wild. Hydrodynamics is elegant. Inefficiency is tiring
 
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A lot of good stuff, great read. My method of most efficient paddling is to make sure my brother-in-law, who is a paddling machine, is in the front of my canoe and that he doesn't look back too often! A long as I make sure we are headed where we want to go I'm usually pretty well rested at the end of the day.
 
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I find this analysis of paddling, by way of the scientific disciplines of biomechanics and kinesiology, under the overarching umbrella of physics, quite interesting. It will be helpful to some. However, the essence of paddling (for the most of us who do it for fun) is found in aesthetics i.e. beauty and spirit. To that end I have two simple contributions to the thread: 1) Physicists theorize that the smallest of universal particulate movement (and therefore all movement) can best be described as "spirit". And that is a beautiful notion. 2) Indeed, maybe the ones who invented the canoe, and understood it as a function of the Great Spirit were onto something.

I agree that the spirit of paddling is a beautiful notion. And I know that my spirit, your spirit, his spirit and her spirit all hold very different notions.

The physics and physiological analysis of paddling, the most effective way to move, correct and recover a paddle, crossbow draw, modified freestylepaddleplant blather all mean damn little to me when I am paddling. My mind is not dwelling on the biomechanics or kinesiology, or any other olgy; I’m just doing what feel right to me in that moment in time and space.

With experience that has devolved into subconscious muscle memory, thoughtlessly doing what works for me while maintaining a mind emptied of all but the immediacy of the world at hand.

That tranquil paddling State of Mind is what I most enjoy afloat, and the time when, emptied of other concerns, I notice the world around me most vividly.

Things like thoughtlessly recognizing the wind and wave riffles on the water and what that means for course and correction, playing current, tides, wind eddies and other miscellanea of the water’s surface without mindful calculation, subconsciously appraising the breeze in the trees versus the flow of water carrying me onward, wind shadows and leeward landforms, tilting a near imperceptible hull lean into a long carved turn without conscious consideration.

Even just settling into a big-water next destination point landmark and keeping on keeping on, stroking without course mindfulness.

I don’t want to there where I’m headed, I want to be here where I am now. I will never be right here, right now again; the river flows on, never to be the same water twice, the tides, seasons, foliage, winds and cheeping of birdlife, frog call, elk bugle or sheer silence all change.

As do I; next year, if I were here in these exact conditions, I won’t be this same me. This is a here and now a never to be repeated moment in time. Appreciating that moment for whatever its right the hell now, it won’t come again, is the essence of tripping.

The spiritual part for me is not thinking about my paddle technique, blade or recover angle, efficiencies or ergonomically “correct” physics. I want to be-there-now, in the moment. My stroke technique may change, I may lily dip, bull my way strenuously into the wind, float ruddering in current using the fewest stokes possible (a game I often play with quiet, empty mind), or peel into an eddy to sit motionless, stop, look and listen.

How I get there is often far from the ACA paddling syllabus of efficient paddling, but it is my personal happy way, allowing me to savor time and place, and need be no one else’s.
 
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