Science behind speed and glide

Hi All
I an having difficulty explaining the concept of efficient acceleration and cruising to some of my friends. I have observed a build up of speed with an occasional pause in the stroke as well as a shorter stroke letting the boat "do it's thing" as opposed to slogging relentlessly.
In my Evo this effect is very observable on my GPS watch.
Is it just the braking effect of tue paddle at catch and drag at the end of the longer stroke?
My friends seem sceptical about the "less is more" aspect.
I seem to intuitively get it, but explaining it in a scientific manner is a problem.

Unless you are a zen master of paddling and have a perfect stroke, you are 'braking' at the catch and exit.

Therefore, fewer strokes with the same total work will have less total braking effect. 

What do you mean by "In my Evo this effect is very observable on my GPS watch."?

I mean that If I take a short pause every X stokes I see a small speed increase during that pause.
Not saying it's specifically this boat compared to my V7 that I paddled until a couple of months ago, but I am noticing it pretty often now. Could be that I finally started to learn, just don't recall seeing that with the V7.
I am talking about instant speed reading on the watch attached to my foot strap.

Glide is getting the max distance per stroke, speed is your personal best combination of distance per stroke times stroke per minute.  For max speed, someone who is really unfit with perfect technique will do better at a lower stroke rate that a super fit thrasher with crap technique.

Most of the useful work of the stroke is done right at the catch for several reasons.  I have heard coaches describe this ideal rhythm in different ways - the "Zsolt Jolt" and "Hit it and quit it" come to mind- but it boils down to the fact that 

1. In a sitting position you can pull harder on an anchor set right at your feet than one at your hip.  Try it- go sit down in front of a fence post or stop sign or whatever and give it a go.  (just not at a busy intersection unless you don't mind getting the cops called on you)
2. The paddle is a more effective anchor when totally vertical in the water, and this happens very early in the stroke.  At vertical, you present the max surface area to the medium and thus can exert max force to propel yourself forward.  

So you put these two facts together and you see that if you focus your effort at the front with a clean catch and really load that blade as soon as you can, you will get the best distance per stroke.  It's not  that you can't exert useful force later in the stroke- with good technique and wing paddles, you can, but the tradeoff is that the further back you pull, the less you can focus on the really productive zone right at the front.  

I suspect that your speed is improved when you are working on "glide" because as an amateur, like 99% of the rest of us, your catch is pretty terrible most of the time and when you really focus on it, the distance per stroke benefit improves so much that it outweighs the fact that you are doing less strokes/ minute.

Edit:  regarding noticing the speed improve when your paddle is not actually in the water pulling:  This is certainly an artifact of the lag between your actual speed and the GPS.  Physics teaches us that without an acceleration an object cannot increase in speed.  Doesn't matter if it is a bullet the instant it leaves the muzzle  of the gun, or a surfski no longer being pushed forward by your butt/ legs/ feet.  The instant you stop applying force to the boat, you are slowing down due to drag.

I am usually able to pick up more speed over time by doing occasional pauses. It feels like the acceleration continues for a short while during a pause. If that was an artifact, it certainly occurs in good correlation with a pause.

SS, maybe put up a vid so we can see exactly what you mean?  If you mean that when you change your rhythm to include pausing before hitting the next catch, and then after a few seconds the speed ticks up then that makes total sense to me.  If you mean that you are cruising along at steady state, then stop paddling and subsequently watch the speed tick up then I'm stumped....
But if it's real, sounds like a win/win race strategy!

This is more like the latter. I cruise with a decent cadence and the speed is steady give or take. Then I literally make the paddle completely dry and watch the GPS for maybe a few seconds and it ticks up a tenth of a km/h and then maybe another tenth. I resume the pace and basically keep up that speed. Then in a while I rinse and repeat each time seemingly keeping the speed gain. The upticks seem to follow during each pause.
I don't know. I am certainly a newbie and may confuse one thing for another but I do find it curious that the upticks occur during pauses. People tell me it's impossible and I am quite confused.
I don't have anything like Garmin Virb and just a simple gopro vid won't be useful..

PSwitzer: it's normal, he has the Evo with the electric propulsion assist, so when he lifts his paddle he no longer slows the boat down and the propeller provides the acceleration .

"If you mean that when you change your rhythm to include pausing before hitting the next catch, and then after a few seconds the speed ticks up then that makes total sense to me"

Even though this is not quite what I am talking about but I am curious about this as well. If we are talking about just adding space before catch and that results in a speed gain then what makes that happen? Seememgly due to slower cadence we are doing less positive work as well as less braking resistance but given the same technique the negative/positive ratio of forces remains the same? I.e. we should be slowing down? Is it the mysterious boat glide (which is more and  more confusing to me). Or is it biomechanical thing such as being able to whip it better due to a moment of rest?

SS, The reason I wouldn't be surprised if your speed improves when trying to pause before the catch is because it likely is making your catch better, more forward and engaged sooner.  It might be pretty subtle but this is why even pros do drills to practice this- when you pause, take time to get the top hand close to your head, really twist out with your hips and nail it up front, you are very likely doing more useful work even with a slower stroke rate.  

Secondary reason that is plausible to me is that when pausing before the catch, you could be getting the time to pause by taking the blade out of the water sooner which is usually a good thing for beginners, almost everyone comes too far back as default when learning.  So less sucking the boat down at the exit= better speed.  

I think that watching the instantaneous speed is misleading. You need to do 2km with one technique, timed, rest and repeat with the other.

A 0.1kph change for a moment when you pause paddling could be down to something like the boat not 'squirrelling' (weaving slightly) as you paddle, so that the GPS is reading a very very slightly higher straight line speed.

Ok, thanks everyone. I will keep an eye on this phenomenon, hopefully figure out eventually what exactly causes it.
So far it's been a good thing that allows for speed build up without a significant effort increase. Whatever it is I will take it

Is it possible that the speed detection device has a millisecond delay?  You plant, rotate, drive, which obviously causes acceleration, then by the time you glide (has to be slowing slightly), the speedometer shows an uptick.  This seems to me to be a delay.  Only if a fraction of a second, mind you.  I cannot imagine a remote device that shows actual , instantaneous results.

No, we are talking a couple of seconds of a dry paddle. Pretty repeatable, enough for me to use to my advantage and build up over several pauses. Consistent enough that I initially assumed that theres some hydrodynamic thing going on hence the wording of this topic. But I have been told repeatedly that's its nonsense so I am at a loss.

This glide in rowing is called 'letting the boat run'. 

 also 

 This is about "eking out the run" and "getting that sensation of effortless movement". It is a real phenomenon SpaceSputnik. 

Another contributing factor  may be "sitting the boat up". In paddling may not apply in singles however certainly in an eight once everyone in the boat concentrates on "sitting it up" no question there is increased glide. Maybe only applies to multiple paddlers/rowers, however you can experience this in a double once both padders are coordinated in terms of balance and stroke. Possibly fair comparison single paddler when you're throwing yourself around the place boat rocking and rolling and not 'sat up'. You may have experienced the sensation when it happens on flat water (no assistance) and suddenly it seems independent of any extra effort or technique change, the boat just seems lighter and flows with minimum effort. I sense this sometimes at maybe 80% effort, certainly not trying just feel this zen-ish moment. (maybe it''s the drugs .. Nnah, kiddin'). Sitting boat up different to the SpaceSputnik pause glide though, more all the ducks lining up as it were.

Thanks Watto. Maybe I am not completely crazy after all
If I could work that in my stroke it would be pretty sweet.

Just added a bit above - you're too quick for me.

Probably stating what everyone knows, but I can definitely see and feel more glide with pausing on my V14 or Mohican on flat water then our V10 Sport or 520.    Have my Garmin do a rolling 3 second rolling speed average really helps (3rd party download app), Mohican  can really notice.   WIth out the 3 sec ave, really hard to see or tell the actual difference IMHO.   I also set my Garmin to auto lap every .5 miles and use Lap Ave Speed as well.

Chris

I haven't felt it in the V7. That boat seems to want brute force more than anything. But then, I am probably not paddling  quite the same as I was when the V7 was my primary boat.