KayakPro K1 SpeedStroke Gym

[...]

I am seeking anyone else within the NSPN community who is using a KayakPro K1 Ergometer or equivalent over the winter months.

I am hoping to share experiences regarding training session frequency, duration, results, etc. Are you using a heart rate monitor? Will you be down loading related software systems such as, eMonitorPro2, VirtuaRace or iRaceExpress?

For those with multiple years of experience, I am interested in hearing how the ergometer helped limit the winter "rust and decay" on your forward stroke.

I suspect this kind of machine is very popular with those training for the Blackburn Challenge as well as the surfski community.

Warren

[lhunt]

Hi, Warren, sorry, no experience with it but I have certainly considered it. I work out in a gym (bleah) during the winter. By "anyone else" are you implying that you have procured one of your own?

Lisa

[...]

Lisa,

Yes, I have it in my basement.

Warren

[leong]

I don’t know if this helps, but here’s a review of the Speedstroke Gym that I read several years ago. The author is a physician and a very fast surfski racer (I see him at the Blackburn most years).

I don’t use the Speedstroke myself because I paddle in warmer climates. However, besides the exercise value, I think this kind of ergometer is very useful for optimizing your forward stroke. It even provides output-power curves.

[...]

Leong,

The review you mention above was the key document which helped me decide to buy the SpeedStroke. For a long time I could not understand why a kayak camper like myslf would ever need a SpeedStroke. Although the machine and I are still getting acquainted, I suspect it will exceed all my expectations and turnout to be just what I needed. It is amazing!

Warren

[leong]

Assuming no blade slippage (a locked blade), a specific paddle (fixed blade shape/size and paddle length) and a fixed hand position on the paddle, your speed is a function of your stroke rate (cadence) and the length of the stroke? But a good forward stroke requires a specific stroke length. So, for a given speed, the only variable that determines cadence is your hand position on the paddle. Accordingly, your hand position serves two purposes: 1. Ergonomically inspired rules of thumb such as “If you place the center of the paddle on the top of your head, your elbows should form slightly less than a 90 degree angle.” (And other such rules) and 2. To vary your cadence.

But why should you care about your cadence; i.e. why does cadence matter for paddling at a constant speed?

The answer is due to Hill’s biomechanical equation. In essence, the equation expresses the change in the speed of a muscle contraction as a function of load. That is, for a given person, Hill’s equation plots force as a function of speed (or cadence for paddling or pedaling a bicycle). Since power is the product of speed and force, at some cadence your power output is maximized. Call this cadence the optimal cadence. So, for example, to paddle as fast as possible you should paddle at the optimal cadence. And, with the constraints as stated above, the only way to vary your cadence is by hand placement on the paddle.

So what does this all have to do with the KayakPro Speedstroke Gym Ergometer? The answer is that I think an ergometer can be used to determine the optimal cadence that results in your Maximal Aerobic Power (MAP). When you’re paddling at the cadence corresponding to your MAP (your MAP cadence) you will go as fast as possible.

Here’s a way I think it can be done. Choose a set of fixed hand positions on the ergometer’s paddling shaft and paddle at maximum effort in turn using each of the hand positions. For each hand position, plot speed, cadence and power. See which hand position results in the greatest speed (and I assume the maximum power). The corresponding cadence is the MAP cadence. And the corresponding hand position is optimal.

I believe that for submaximal efforts, there is another cadence, the Energetically Optimum Cadence (EOC). The EOC is that cadence that you would use for endurance, not for all-out sprinting. I think the EOC for a given speed is that cadence that minimizes the power required to go at that speed. The EOC is probably not equal to MAP and it probably varies as a function of speed.

Here’s a possible experiment with the ergometer to determine EOC for various speeds. Just paddle the ergometer at different constant speeds at less than maximal efforts using various hand positions. For each speed the EOC is that cadence (and its corresponding hand position) that minimizes the power you are putting out.

Perhaps the KayakPro Speedstroke Gym provides similar or better ways to determine the MAP and EOC. I wish I had the device to experiment for myself. I’ve been trying to determine optimal paddle length (note, my Epic wing paddle is length adjustable) and hand placement. But without a laboratory set up like the KayakPro device it’s very difficult to do out on the water when waves, current and wind conditions are variable.

Respectfully,

-Leon

[...]

Leon,

I can understand why many paddlers use the SpeedStroke Ergometer to assist them in improving their speed. You are correct in that all the normal distractions, such as waves, wind, etc. are removed. When you combine your efforts with video recordings (front, rear, side) you can perform amazing analysis.

Without a doubt, it is the most amazing piece of exercise equipment I have ever used. For me, it is worth every penny.

Leon, my use of the Ergometer is perhaps different from what you seek. I need it to improve my forward stroke so I can log miles during a 13 day Alaska expedition and feel no significant discomfort or fatigue. I also use it to build strength and endurance as well as experience the joy of paddling when weather and time just does not permit me to get outside.

I am now into my third month using the Ergometer. I have teamed up with John Carmody to improve my forward stroke. Every four weeks I prepare a set of three videos taken from the three angles noted above. Together we analyze my technique and John recommends very specific actions to improve. The Ergometer permits me to have a laser focus on the areas needing work and we both feel I am making significant improvement.

Approximately one week ago I went for a paddle on Casco Bay. I was interested in determining how it would feel to transition to a real world of paddle and boat. Surprisingly, the transition felt good. Actually very good!

Living here in New England and having a long cold winter season, I am honestly surprised more paddlers do not own a KayakPro SpeedStroke Gym Ergometer.

Warren

[EEL]

Living here in New England and having a long cold winter season, I am honestly surprised more paddlers do not own a KayakPro SpeedStroke Gym Ergometer.

Warren:

I can think of two reasons. 1. Cost. 2. Preference for spending the winter cross training by skiing or other activities which has the added benefit of avoiding the mental fatigue/burnout that occurs if you focus on only one activity intensively for a long time. That said, does sound like a wonderful way to improve and hone your paddling stroke.

Ed Lawson

[leong]

Leon, my use of the Ergometer is perhaps different from what you seek. I need it to improve my forward stroke so I can log miles during a 13 day Alaska expedition and feel no significant discomfort or fatigue.

Warren, I think you’re making good use of your ergometer. But you can have a picture perfect forward stroke and still not be as efficient as possible. I don’t think that what I proposed is inconsistent with your goals. Here’s an analogy:

Say you want to pedal a bicycle all day at a reasonable cruising speed. There is some gear ratio that you should use that will result in an efficient cadence for that cruising speed. Using a higher or lower gear ratio will only waste your energy.

For kayaking, the length of the paddle and where you place your hands on the shaft are analogous to the gear ratio of the bicycle.

Bottom line: I think that what you’re doing with the ergometer is excellent. When you have a good forward stroke you’re freely-chosen cadence will probably be about right. I’m only suggesting incremental biomechanical improvements that can be obtained from paddling at your optimal cadence. Using the scientifically determined correct length paddle (and scientifically determined hand position) will help get you even closer to the optimal cadence, so it’s a free lunch after you’ve done the experimental determination as I suggested.

-Leon

[...]

Ed, you are correct, no one should focus their exercise program on only one machine. But the Ergometer is very addictive for me. I close my eyes and think I am out on the ocean when reality is the outside temp is 0 degrees. Then I open my eyes, and realize I need to get to work!

Leon, you are correct about the paddle length and hand placement on the paddle shaft. Both make a hugh difference for me. It might be useful to know the Ergometer does facilitate proper hand placement, but the bar (it's version of a paddle shaft) is a fixed length. No ability to modify the length, but since there are no paddle blades, does not seem to present a problem.

I have noted one issue which was identified in the web article you mentioned earlier in this thread. Since the seat is fixed, you need to readjust your mind when you get in your boat. The hope is a future enhancement will allow for the switching out of the stock seat for a seat that moves more freely.

Warren

[EEL]

For kayaking, the length of the paddle and where you place your hands on the shaft are analogous to the gear ratio of the bicycle.

Leon:

Wouldn't blade size also be analogous to gear ratio? In the sense you can move faster at the preferred cadence assuming you have the strength to maintain the preferred cadence against the higher resistence. It seems to me selecting blade size is also important to achieve the optimal cadence for EOC as is training at that cadence rate. Much as most beginning cyclists have to work at developing the ability to "spin" to be able to pedal at the preferred high cadence rates.

I have often noted that paddlers with a fast touring speed (4-5 KTs) seem to have higher cadence and shorter strokes compared average paddlers. I don't know if there is a tendency toward longer strokes with lower cadence, but they seem to go together.

Ed Lawson

[leong]

Leon:

Wouldn't blade size also be analogous to gear ratio?

Yes, of course. I dispensed with the blade size and stroke length in my earlier post when I said,

“Assuming no blade slippage (a locked blade), a specific paddle (fixed blade shape/size and paddle length) and a fixed hand position on the paddle, your speed is a function of your stroke rate (cadence) and the length of the stroke. But a good forward stroke requires a specific stroke length.”

I’m particularly interested in where to place my hands beyond the standard rules of thumb. Just a small change makes a big difference. It’s just that I can’t accurately determine the optimal position w/o experiments with something like an ergometer.

A few days ago I did a fast 22-miler with two really fast guys. I had trouble keeping up until I choked up (hands closer to the business end) and it drove my cadence up a lot.

My rule of thumb for blade size is to choose the smallest blade that locks (but this probably doesn’t apply to GPs). Of course, even very large blades slip a little. There is a tradeoff between the loss of efficiency when a blade slips and the possible gain from the resultant increase in cadence. But I think the best way to get the increase in cadence is via paddle length and/or hand placement, not a slipping blade. Of course, you still have to worry about ergonomics; i.e. is the paddle long enough for the boat’s width and can you completely bury the blade when you’re choked up a lot?

[leong]

Leon, you are correct about the paddle length and hand placement on the paddle shaft. Both make a hugh difference for me. It might be useful to know the Ergometer does facilitate proper hand placement, but the bar (it's version of a paddle shaft) is a fixed length. No ability to modify the length, but since there are no paddle blades, does not seem to present a problem.

Warren, I thought it might be possible to re-connect the cables (or whatever connects to the bar) closer to the middle of the bar. That would in effect reduce the length of the simulated paddle shaft. But it was just a dumb guess on my part.

-Leon

[...]

Leon,

On the SpeedStroke I use, there is not way to reconnect the bungee cords to a different location on the bar. You can adjust the hand placement.

I find the greatest feature of the Ergometer is the ability to focus your attention on many critical actions, which together may give you what you seek. Also, being able to video tape the progress is key and more difficult with a moving boat. Plus, it is hard to know what the paddler is doing with their legs and pelvic bones when sitting in a boat.

Warren

[leong]

Warren,

A friend recently asked if his/her paddling angle was too high. It definitely was not. But it got me to think about what others believe about the efficiency of high versus low angle paddling. From here it says:

“Finally, most paddlers will find the low angle stroke to be better at conserving energy. As a famous kayaker supposedly once said,’ you never see anyone paddle in at the end of a 20-mile day using a high angle stroke.’”

I disagree with the above; i.e. if you’re in good shape and have a good forward stroke I think the high angle stroke is more efficient, whether for racing or cruising.

First we need a definition of efficiency for paddling. Let’s define it this way:

Paddling Efficiency at forward speed S = S divided by the power used to move the kayak at this speed

Here’s where you come in Warren, with your KayakPro K1 SpeedStroke Gym (oh, I’m so jealous). Would it be possible to “paddle” at a set of constant speeds and look at your power output at each speed? Do one such set using a high angle forward stroke and the other set using a low angle forward stroke. Then compute the Paddling Efficiency as above.

My guess is that that the paddling efficiency for the high angle stroke will be greater than it is for the low angle stroke. And in the real world the actual efficiency differences will be even greater. That’s because in the high angle stroke the blade passes closer to the boat. Hence, more of your power is used to move the boat forward; i.e. you don’t waste as much power yawing your kayak left and right.

Not that I’m against low angle paddling some of the time. For example, here’s what I said to my friend:

“… when in very rough water it might be a good idea to decrease the stroke angle somewhat. That’s because each lower angle stroke becomes more like a low brace and the lower angle keeps the top blade ‘closer to the water’s surface and out of the stronger winds that are higher above the surface’. Sometimes it’s a good idea to vary your stroke angle. That’s to change the muscles being used; i.e. give a rest to some of the arm, shoulder, and trunk muscles.”

I use low angle paddling a lot of the time when I'm paddling slow with friends

Leon

[...]

Leong,

It might be helpful to know, the Standard On-Board Console of my KayakPro SpeedStroke has the ability to collect and display the "Power Output in Cal/J" as well as the Stroke Rate, Heart Rate, etc. You can then connect the console to PC Software such as, "eMonitorPro 2" and "KayakPro VirtualRace" and others. By the way the developer of the product, who I believe is Grayson Bourne, and I spoke on the telephone several times during the purchase process. He is very knowledgable and helpful.

I can tell you I use it every week and it was extremely helpful to me in preparing for my recent trip in Alaska. I always paddle high angle and before training I would feel fatigue in my torso. My training began in October of 2013. During the six weeks leading up to my flight to Anchorage, I was up to training seven days per week for two hours per day. My body went thru a significant change in form and function. I am now back down to training four times per week for two hours per day just because I love being on the SpeedStroke. In many ways it is like being in my kayak.

Warren

Edited August 2, 2014 by Warren

[leong]

Warren,

I know, I know, it's a super gadget. If you have the time would you please try my experiment? It might prove that high angle paddling is always more efficient, or maybe not. Either way it could be a "solid" contribution to paddling knowledge, as opposed to some of the fuzzy and innumerate conclusions that appear in the literature.

-Leon

[...]

Leon,

I will be able to carve out some time next weekend to try the experiment. This weekend is all family cookouts.

I will get back to you!

Warren

Edited August 2, 2014 by Warren

[leong]

Thanks, no hurry.

[leong]

Warren,

After I designed the experiment above in this thread I went to the gym to workout on a rowing machine. While sweating away I realized that I made a mistake in the definition of efficiency. The correct formula should be:

Paddling Efficiency (at forward speed S) = S divided by your body’s input power to the SpeedStroke

Unfortunately, unlike output power, I don’t think the SpeedStroke has a direct way to measure your body’s input power. But studies have shown that your heart rate (HR) is directly related to your body’s input power. Therefore, HR can be used as a surrogate for your body’s input power.

However, there are a few caveats and things to consider when using HR to estimate input power.

1. For a given output power, there are slight fluctuations in HR on a day to day basis.
2. HR doesn’t instantly increase the moment more power is produced.
3. As you become more fatigued, your HR continues to get higher (up to a point).
4. HR takes about 90-120 seconds to fully respond to a change in effort.

Nevertheless, given all the data collected by SpeedStroke (like you said: Power Output in Cal/J as well as the Stroke Rate, Heart Rate, etc.), I think some of that data could be used to help smooth out any spurious variations in HR. Thus, smoothed HR might be accurate enough to use as a stand-in for your body’s input power.

So the revised estimate of efficiency would become:

Paddling Efficiency (at forward speed S) = S divided by your HR

Here’s the revised experiment restating for your convenience:

Would it be possible to “paddle” at a set of constant speeds and collect your HR (and all other data) at each speed? Do one such set using a high angle forward stroke and the other set using a low angle forward stroke. Then compute the Paddling Efficiency as immediately above.

If I made any other stupid mistakes please chime in (anyone). Also, does anyone know of a better way to measure input power (like calories burned per unit time) beyond connecting a device to your mouth and nose that measures the gas exchange during exercise.

-Leon

PS
Again, there’s no hurry. It’s just a potential way to use SpeedStroke to compare the relative efficiencies of high angle vs. low angle paddling.