I had RIM running in the boat today (as usual) and since I haven’t rowed at these high rates before, I decided to take a look at the stroke accelerations and see what flaws I could see. Turns out they are readily apparent.
First, for comparison, here are some nice steady state strokes at 23 and 24 spm.
See that nice smooth drive at 23 SPM (purple). Then as the rate goes up to 24, you can start to see the appearance of the double hump in the drive. That’s is me opening my back early.
Next, here are 3 sets of strokes when I was trying to hit targets of 26, 28 and 30. They actual rates were a bit higher. I guess I was over eager.
The double hump continues to be more pronounced and you can begin to see two other flaws. First is a disturbance at the finish (around 0.8sec). That is me starting to get sloppy as I try to get back up the slide more quickly. The other is a gradual rise in acceleration during the recovery (starts at 1.2sec at r30). But still, not horrible.
Now we look at r34 and r36. These are a bit harder on the eyes.
The double hump is now significantly more offensive, there is a pronounced blip at the finish and I am clearly accelerating as I move up the slide versus maintaining a steady speed from the handles all the way through the legs on recovery. The miracle here is that I actually rowed at these rates at all.
Lastly the ugliest of the bunch. Here are three blocks of strokes at 38 to 40 spm.
Same flaws as before, only more pronounced. It appears that going from 38 to 40spm does not enable me to make the boat go any faster. In fact, now the double dip is so pronounced that acceleration goes almost all the way down to zero in the middle of the drive.
So, what to work on. I need to work on not opening my back. I think the prescription is a set of 20 stroke intervals between 30 and 36 spm with enough paddle time so that I am working on technique instead of fitness. This will get into the program next week after the race.
Quantified Rowing 
Two posts from the Rowing in Motion site.
1. http://www.rowinginmotion.com/improve-your-stroke-avoid-the-drive-hump/
The second is a discussion of a certain Masters 1x rower’s stroke:
2. http://www.rowinginmotion.com/rowing-analysis-masters-1x/
😉
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By the way, I do want to point out that your speed values are higher for the 38 and 40spm than for the 34 and 36spm. Also, your 40spm is slightly faster than your 38spm. 😉
More data needed
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I have to admit, im struggling to see the issues in the curves that you mention? To me the acceleration curves all the way up to 40+ actually look quite good, you seem to be getting hung up on the “double hump” or “drive hump” that your curve is showing as the rate comes up, but that is something that is actualy a characteristic that is shown by an Olympic gold medallist when they had compared to a national level rower (see below)
Click to access 2012RowBiomNews11.pdf
Also Rowing in Motion mention that from their findings, the “shape” of the curve like this seems to be more of a fingerprint of someones stroke, rather than an perfect curve that everyone should be trying to get, which makes sense as we are all differently made.
So Instead of stressing about the shape of the curve, work to improve parts where its not as smooth as it should be, and to my main points are that at 26, 28, 30 there is a noticeable “step” at the end of the finish, suggesting you are pressing on the footplate before you place the blades at the catch, so make sure to place the blades before you drive and be more relaxed at the catch.
Otherwise the curve looks pretty good
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Tom, thanks for taking a look. And I appreciate the feedback. I’m focused on the double hump because it seems to be a symptom of two “real” problems. One is opening my back too early in the drive, the other is going to deep at the catch and then coming back to a good depth. I have found that when I am managing those flaws well, I’m faster and the hump is more of a plateau or ramp. You point about the catch is a very good one and it correlates to an observation made by another sculler last weekend, that I am raising my blades up as I square and starting to drive before the blades are buried.
Oh what I wouldn’t give for a real coach in a launch hectoring me through a bullhorn!
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