My brother-in-law and I have a tandem that we raced in last weekend. We do not paddle synchronously. There is a center hatch in the tandem so we are positioned far enough apart that we do not have to paddle in sync. I’ve been told that we should paddle in sync but do not understand why. We have tried to paddle in sync but that slows my cadence way down and I would assume the kayak would also slow down as a result. Why paddle in sync? I do not understand and was hoping to find sound documentation explaining the reasoning behind it. I’ve searched the web and have not found any articles explaning why we should paddle in sync. There are pleny of videos of K-2 racers doing it but they are also seated close together and have to paddle so as not to bang paddles.
In sync not as important with enough
spacing between seats. Most tandem kayaks have the seats so close together that the paddles will hit each other if not in sync.
It would actually make sense…
…to paddle 1/2 stroke out of sync. With a kayak paddle, the boat slows slightly between the left and right strokes. If two paddlers were a half stroke out of sync, it would cut the time between strokes in half and, at least in theory, maintain the speed of the boat better.
here is something tot read about
in-sync is very important
If you want to be fast.
Imagine this, you take your tandem out solo, every stroke you take has to be strong enough to move you through the water. It’s a big boat. Now add the weight of another paddler. Even more resistance to move through the water. Now, visualize having the energy needed to move the boat cut in half. That’s what paddling in sync does for tandem paddling.
Sure you can paddle out-of-sync and be quick, but if you want the cutting edge, you and your partner will have to learn to paddle together. Try working on it and don’t worry about the speed. Once it is effortless, increase the cadence. The bow person sets the pace and stern matches. Sounds like you need to encourage your bow paddler to increase their cadence. When I train, I listen to music with a quick rhythm to keep my stroke rate up. Perhaps it’s worth taking some tunes and small speakers to assist in your pace-keeping endeavors.
Science of paddling
Thanks for the article. It makes perfect sence for the conditions he covered. Now my partner and I need to figure out how to paddle in sync. For every three strokes I take, he takes two. For this reason we’ve never put any focus on paddling in sync. I guesss I need a larger or longer paddle and he needs a smaller or shorter paddle? Currently I use an Epic small wing at 217 cm. He uses a Werner Euro style, low angle paddle at 230 cm.
Actually, it does not
To be efficient/fast, the strokes have to be 100% on sync; otherwise, one is using 1/2 the torque to move the boat with twice the weight.
To paddle a tandem boat is not an easy task, even at the Olympic level is more about the sync of the athletes than the combined power.
He needs a much shorter paddle
or you guys will never be in sync.
Your paddle length is probably fine.
The two paddlers in a tandem kayak have to be compatable, and you taking a extra stoke to every two of his won't get it.
Either he has to pick up his cadence, or you have to slow yours down.
Needless to say, if you slow yours down, your speed will drop off.
So--- logic follows that: (continued by you)!
My wife and I used to have a West Side 23 foot long tandem "Bullett" and enjoyed every minute of our in synch paddling.
Who is winning the races you’re in?
If it is all folks paddling in synch who are winning, you may need to look at your own strokes for some improvement so that you can paddle together effectively.
Shawns article was written
for single blading. He is a marathon canoe racer. It seems like paddling out of sync with a double blade would minimize yaw while paddling in synch would maximize it.
Canoeists paddle opposite sides.
Despite the focus on single blading, the forces described would work exactly the same for a tandem kayak.
A non-scientific way of description that made sense to me, is that if people are in sync, their thrust combines to move the boat. Out of sync, each person is individually responsible for moving the mass, and overcoming the drag on the hull. This was a coaching dogma, for sure, but it made sense and brought results (this was in my days of racing marathon canoes, but mostly tandem and 4 person flatwater racing kayaks). In particular, with the forces we would apply in true racing kayaks, we felt we were literally suspending our weight onto the paddle- less weight on the seat, huge connection between paddle and footboard.
We used to work a lot on force synchronicity- while paddling, one would keep their eyes closed and feel the timing of the blades in and out of the water. Very helpful. When I coached juniors in racing tandem kayaks, I employed with great success a variation I came up with when I coached rowing. If the timing in/out is good, then the pair paddles with one at power, and the other with zero power but still matching the timing. The person not applying power “feels” their partner’s power application. Taking turns at this, the next part is to take turns trying to copy the partner’s power application. Very cool drill.
As far as the yaw issue (canoeist paddle on opposite sides), I wonder about this. I somewhat think it might be beneficial for the tandem kayakers, while still paddling in sync, to paddle on opposite sides. The intent is to reduce yaw. To some extent, a rudder would compensate very well (a likely situation with tandem kayaks, anyway, and the major distinction why canoeists do paddle on opposite sides).
There is a reason why tandem kayakers in race kayaks paddle on the same side. Partly, it is impossible to do it any other way, since the seating is so close. More importantly, given the extreme tippiness, it actually is worse when paddling on opposite sides. In race technique, the body mass is rarely directly over the keel line during the power application. For years, there was disagreement about what was better, mass towards the paddle, or away. Seems like the majority of top paddlers now appear to almost counterbalance their torso away from the paddle. Anyway, it gets real goofy if the paddlers are doing this out of sync in a tippy boat.
In your sea kayak, not sure. Get a GPS, and heart rate monitors, and try it out both ways. If you can hold a higher speed at the same heart rate, go for that style.
And above all, lose the 230cm paddle!!!
You mean 1/4 out then
1/2 out would be front-left and back-right stroke simultaneous. So there is still an in-sync recovery phase where no power is being applied.
You seem to be suggesting that there is always a power stroke happening.
…but it does not work that way
the catch and exit needs to happen at the very same time.
In fact, you don’t need a stroke at all times, you need a stroke at the right time. When both paddlers apply an equal force at the very same time, they are equally sharing the drag and weight of the boat and paddlers. If one is out of sync each paddler is having to move the whole drag and weight of both paddlers and heavier slower boat than a k1.
That statement would be true if only one person were paddling for an extended time, but it's a long way from being true for a person who applies their paddle stroke to a boat this is already in motion as a result of both their effort AND the effort applied by their partner.
I sometimes row my guide-boat from the front seat with a passenger in the rear seat who uses a canoe paddle (that's standard procedure for two-person propulsion of a guide-boat). The passenger is very small, and a decent paddler but not very strong, and we are never in synch with each other. Still, her contribution to propulsive effort is hugely beneficial to the movement of the boat, and there's a night-and-day difference between how the boat feels relative to my rowing effort when she's paddling and when she's not. When she paddles, the boat goes a lot faster relative to the effort that I'm applying to the oars, and I can even back-off on my rowing effort while still enjoying a noticably faster ride.
I can't say for sure how much difference it makes to paddle in-sych versus out-of-synch, but experience shows that out-of-synch paddling is NOT inefficient to the degree, or even for the reason, that you describe.
I suspect that it is actually better to paddle out-of-synch, to keep the boat at cruising speed while MINIMIZING the degree to which that "burst of speed" is applied with each stroke. Here's my logic: The resistance to forward motion increases exponentially with speed, especially at higher speeds. If the same average speed can be maintained by reducing the amount that the boat slows down between strokes INSTEAD of by increasing the burst of speed during each stroke, that would reduce the amount of energy that is wasted on exponetial increases in resistance to motion of the boat. If the same amount of power is expended but the peaks of resistance are reduced, it makes sense to me that less energy would be wasted for a given rate of travel.
Okay, I read that article, and can see the logic there too, getting farther into the high-resistance zone and not slowing down enough between strokes to create the same average speed as that obtained by out-of-synch paddling. STill, from a standpoint of pure efficiency of power application rather than from the point of obtaining maximum speed, I suspect that my out-of-synch idea might still be correct.
In any case, to say that paddling out-of-synch puts the full burden of propulsion on each paddler during the moment of power application (also purported to be true in a post below this one) is not true for the reasons I provided initially. One paddle stroke by one person need NOT be applied at the same effort when maintaining a give speed as would be necessary if only one person were paddling, simply because the effect of the other person's power stroke is still in effect at the moment you apply your own power stroke. That's behind the reason for my rowing/paddling out-of-synch observation described above.
Paddling in sync may yield higher speeds, but I wouldn’t make that statement based on the linked article. There are some gross assumptions (no viscous drag, constant velocity during power application) that are problematic. Also, there isn’t a consideration of cadence, which is to say, for in-sync paddling, the deceleration between strokes is critical, and the amount of time spent slowing down depends on the cadence.
The assumption of constant velocity during power application means that the local acceleration of the boat during power application is neglected (the term m dv/dt). An important fraction of the paddle work is expended on re-accelerating the mass of the boat after drag (viscous and friction) has slowed it down. This is the essence of the difference between in-sync and out-of-sync paddling, so cannot be neglected.
As an aside, I note that the integral of paddle force over time is impulse, not work, as stated. If the velocity is constant, work = velocity times impulse, but the velocity varies.
I can’t take the final graph at face value, although I give a lot of weight to the opinions of those who have actually raced tandems. In-sync may be the way to go, but it would take a more complete analysis to prove it.
"I suspect that it is actually better to paddle out-of-synch, to keep the boat at cruising speed while MINIMIZING the degree to which that “burst of speed” is applied with each stroke. Here’s my logic: The resistance to forward motion increases exponentially with speed, especially at higher speeds. If the same average speed can be maintained by reducing the amount that the boat slows down between strokes INSTEAD of by increasing the burst of speed during each stroke, that would reduce the amount of energy that is wasted on exponetial increases in resistance to motion of the boat. If the same amount of power is expended but the peaks of resistance are reduced, it makes sense to me that less energy would be wasted for a given rate of travel."
I think you have it correct here - the quadratic variation of drag with velocity is the key. Also, boundary layers behave themselves better at constant velocity, rather than being subjected to oscillation.
… after reading that article and thinking about this some more, I modified my post to mention that I’m thinking about pure efficiency of applied effort, not attainment of maximum speed. Racing is a whole other world in that regard.
It’s a shame athletes do not apply you’re theory
Not sure what you are LOLing about. Quadratic variation of drag with velocity is not a theory. I’ve already said that I trust the opinion of experienced tandem racers. And BTW, it’s spelled “your”.