Comparing speed and efficiency of single vs. double blade paddle

[Tsuga8]

Yes, I've been thinking of doing just that. I'm hoping someone will volunteer to send me a longer carbon double for the test.

Alan

I was just thinking myself how a longer carbon double would be nice.... I suspect I'm stuck with what I have, but maybe someone will donate one to your cause

 

[Jim Dodd]

Good test Alan
Using the same hull, eliminates the variable, you will find in the Olympic races, between single and double hulls.

Years ago, in The Iowa Games, I distinctly remember, a kayaker leaving me in his wake.
I attributed it to the hull differences, and the fact the Kayaker was in far better shape, and lighter weight.
Like others, I was surprised at the difference in your test.

I noted the sliding seat. Did you change seat position, between single, and double blade ?

 

[gumpus]

Thank you for doing the test Alan!!!. I'm a little surprised that the double didn't do a little better with someone that knows how to use both types of paddles but on the other hand I've sometimes thought that I have a fixed amount of energy and it's easy to use it up with either type of paddle.

Technically I think we can't assume that the results are precise since it would take a lot of data to prove that something like a 6.6 vs 6.7 mph top speed is real, but I think you controlled the variables much better than I've ever done. It's tempting to just conclude that there is "no significant difference". But some of the differences aren't small. 4.1 mph is only about 5% faster than 3.9 mph but Sean Burke's book points out that speed is proportional to the cubed root of power (doubling your speed takes 8x the power) so the 5% speed difference represents a 15+% difference in power or efficiency which may be HUGE in the paddling world.

I'd be happy (willing) to run some tests...maybe I can do 0 degree vs 6 vs 12, but my DB skills are pretty much non-existent.

 

[Alan Gage]

I noted the sliding seat. Did you change seat position, between single, and double blade ?

Same seat position. I tried my best to keep everything the same between the runs.

I was initially going to do the single blade one day and the double the next but on the first evening when I did the single blade test there was a roughly 10mph wind and the next evening, when I was planning to test the double, it was nearly flat calm. So I re-ran the single blade test right after I finished up with the double.

Alan

 

[gumpus]

I do wonder how much energy is wasted by the yaw from the double blade.

Great stuff, Alan.

I also wonder about yaw losses. I saw one technical paper that said yaw losses were over 10% for Olympic kayaks. I'm just curious how much effort should be spent trying to make a boat go dead straight and I'm also curious whether the losses are worse with a straight keel boat that resists yaw or a rockered boat which yaws more but is also easy to "power skid" the bow back on target. I've asked Sean Burke and one other expert and both said "I don't know, it's complicated".

 

[Steve in Idaho]

The links below should give you an idea about their boats.

Benson

Thanks, that helps. I can see there is some difference, but it's not obvious other than the profile. I wonder what the measurements are.

Hey Grok - what are the physical differences between Olympic K1 and C1 sprint boats?

• Kayak (K1): Olympic sprint kayaks are narrow, sleek boats, approximately 5.2 meters long with a maximum width of about 51 cm and a minimum weight of 12 kg. They have a closed deck with a cockpit where the paddler sits, often equipped with a spray skirt to prevent water entry. Kayaks feature a rudder under the hull for steering, controlled by foot pedals. The hull is designed to be rounded to minimize water resistance, making them fast but less stable.
  
  
  
  
  
  
  
  
  
• Canoe (C1): Olympic sprint canoes are also about 5.2 meters long, with a minimum weight of 14 kg. They are typically open or partially covered at the front and back, with a minimum open section of 280 cm. Unlike kayaks, canoes lack a rudder, requiring the paddler to steer using the paddle. The hull design is slightly different, often described as a "delta" shape in some contexts, prioritizing stability for the kneeling position, though still narrow and less stable than recreational canoes.

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  Hmm. We left out the C1 width. Hey Grok, what is the width of those c1 boats?
  

  The width of Olympic sprint solo canoes (C1) is not explicitly fixed by a maximum limit in the International Canoe Federation (ICF) rules, unlike kayaks, which have a maximum width of 51 cm for K1. Instead, the ICF specifies that C1 boats must be at least 5.2 meters long, weigh a minimum of 14 kg, and have an open section of at least 280 cm in length. The width is typically around 70-80 cm at the widest point to provide sufficient stability for the kneeling paddler, but exact dimensions can vary slightly depending on the manufacturer and design, as long as they meet ICF competition standards. For precise measurements, specific boat models from manufacturers like Nelo or Plastex would need to be checked, but 75 cm is a commonly cited approximate width for C1 boats.

Looks like we really can't use this as a comparison between double blades and single blades

 

[Cruiser]

Let me first say Allan, "Thank You" for taking the time for testing and moving the discussion away from opinions and more to fact based discussion.

I really like the "effort" based control idea, giving the same effort to both paddling modes seems like a good control mechanism .... for getting same effort to each paddle situation.

Using that short paddle makes me wonder if you are trying to graft a "Kayak" stroke to the canoe, instead of using a Canoe stroke. It is fine either way, but I have never heard anyone say they were happy, with the performance, using a kayak length twin in a canoe. The almost straight down paddle position and pull is very similar to the single stroke mechanics, while a canoe stroke is quite a different animal.

My thinking is that you need to take a full stroke to maximize power/efficiency, no matter what equipment or technique you are using. Kayak stroke and single stroke are usually close to the hull and I would expect similar "SPM" rates, just like you reported. However, the longer blade for a canoe stroke places that blade further away from the boat and the sweep arc of each stroke is significantly longer, the blade stays in the water much longer, so it would be expected that the SPM rate would be much lower. The cadence for a canoe stroke is quite different and slower for the same amount of "pushing water" time.

Something else that likely needs to be defined is the blade area, if the SPM is the same, blade area is going to matter , as is stroke length ... that points right at individual paddling mechanics ... I would like to think that holding the effort, via heart rate, would likely offset/identify/mitigate those differences, but also means small observed differences aren't likely going to be reliable.

Blade style performance always comes up as the primary point, but another aspect of this whole subject, that doesn't seem to get much discussion, is the difference in the actual mechanics of single versus double. Not every one is built/able to comfortably use either double or single mechanics in a canoe, that is just life. I think it is important to take the time to learn about the available paddle options and figure out what will work best for you ... there are very few things in life that are "one size fits all".

 

[yknpdlr]

I have no doubt that a single blade paddled on one side only, even with very efficient and rapid rare inefficient necessary correction strokes will be significantly slower overall than rapid hit/sit and switch technique. I can't imagine being competitive in any race in any canoe by paddling on only one side for long distance exclusively.

At this spring ice out happened around the beginning of April, I began my on-water training for the first of the year Adirondack Round The Mountain race to be held in early May. I have a canoe single blade style paddling machine that I train on during the solid water months, and felt my single blade training on it had been normal and painless throughout. This year I had no planned race partner but planned to do the RTM race anyway, so I would be forced into the solo-rec class, which requires a boat under 16' and use of a double blade kayak paddle in a canoe. I have a new 17' SR Blackwater, a length that does not qualify for solo-rec, so I would have to paddle the race after training for the race in my PB Shadow or the slightly slower Rapidfire.

As much as I dislike to use a kayak paddle in a canoe, that was to be my on water training plan for the month of April. I hoped none of my lake neighbors would see me on the lake paddling in that mode. I soon developed a return to a past very painful lower lumbar disk displacement condition, both while paddling double and especially when lifting the canoe out of the water. All due to back and forth torso rotation and strain with the double blade, so I felt.

Well beyond my past usual 2 week long period of fighting through the lumbar pain issue with PT exercises I had been given, this time at 6 weeks I sought further medical help with a series of spinal injections and a new professional PT routine.

The Blackwater weighs only 19 pounds even that was painful to pick up to carry, so I did not feel I could do the short uphill carry with any canoe to get around the Saranac lower dam in either the Shadow or heavier RF without risking either my back or the canoe if I dropped it. So I did not participate in that usual early spring race. Accepting that, when I returned to single blade training, I felt no pain during or after a workout paddling session but lifting the boat from the water was still painful. I believe that my single blade stroke is substantially as outlined in the Tahitian video technique, with the recommended minimal single blade torso rotation.

I am single blade paddling pain free today. Lifting the boat has also much improved.

 

[Alan Gage]

Using that short paddle makes me wonder if you are trying to graft a "Kayak" stroke to the canoe, instead of using a Canoe stroke. It is fine either way, but I have never heard anyone say they were happy, with the performance, using a kayak length twin in a canoe. The almost straight down paddle position and pull is very similar to the single stroke mechanics, while a canoe stroke is quite a different animal.

Yes, it certainly was a pretty vertical stroke. I tried to drop down for lower angle but because of the short length and muscle memory that did not work very well so it was mostly at a high angle. I know this is not what's normally used in canoes but, never having used that style, I can't say for sure how much difference it would make.

The county nature center is on that lake and they rent recreational kayaks so I'm sure they have some longer paddles I can get ahold of. They certainly won't be carbon but for such a short paddle I don't think it will make a large difference.

Alan

 

[yknpdlr]

those who do well paddling with a kayak paddle as is required in the solo-rec race class, will use a relatively short paddle in almost vertical format. e.g. Joe Moore, owner of Placid boats, has won almost every solo-rec race he has ever entered. I won over him just once when he suffered an injury during the race.

 

[Steve in Idaho]

those who do well paddling with a kayak paddle as is required in the solo-rec race class, will use a relatively short paddle in almost vertical format. e.g. Joe Moore, owner of Placid boats, has won almost every solo-rec race he has ever entered. I won over him just once when he suffered an injury during the race.

It still boggles my mind that the race would require paddling with a double. Surely there's a reason for that, but I can't think of a good one - unless the single is viewed as an unfair advantage.

 

[Gamma1214]

...but I feel that sit and switch is the best for comparing the single vs the double.

Makes sense. The inside of the boat would remain much too dry using same-side correction strokes.

Seriously, a great effort to eliminate variables. If I'm ever in a hurry to get where I'm going, I might sit & switch (but probably not), my days of flailing away with kayak paddles are definitely behind me.

 

[Alan Gage]

The inside of the boat would remain much too dry using same-side correction strokes.

When I'm using a switching technique at regular tripping speeds the boat stays very dry unless there's a headwind. I'm not trying to make my switches super fast like a racer would so when I switch sides I fling the blade across in a horizontal arc. It's nothing complicated but hard to explain. This flings the water forward as the paddle passes over the canoe and nearly all of the water clears the bow rather than landing in the boat. Unless there's a headwind that blows the water back. Then it can get a bit damp. Sadie was particularly disgruntled on those days with headwinds as most of it then landed on her head.

Alan