row 2000 meters 8:40.4
row 1200 meters 4:15.0 (1:46.2 / 31)
row 800 meters 2:49.8 (1:46.1 / 31)
row 2000 meters 8:17.1
50 leg raises
Pete Marston Comments
My first comment would be don't change anything too drastically with a week to go before a race, I would certainly recommend not changing the drag at this stage as the chances are whether you go up or down you will go slower because you'll not be using the drag you've trained yourself to be efficient at.
The relationship between stroke rate, drive power, and therefore pace, is generally different in racing or training. It is probably best at this point just to consider racing, or going as fast as you can for a set distance. In this case it is a trade off between stroke rate and drive power to get the best pace you can. The ability to make this trade off is what seperates the good racers (or time-triallers) from the not so good in my opinion. A lot of people fall into one of two categories - like you where to go faster you simply pull harder the same number of times each minute. Or those who keep the power the same and just apply it more times each minute (increase the stroke rate). Neither of these are optimal though. What you actually want to do is as you increase the stroke rate you gradually decrease the stroking power for a set distance.
For example let's take your best 2k of 7:05 at 25/26 spm. If you were to simply keep the power the same and increase the rate to 27spm it would be unsustainable. If you were to keep to 26spm and pull harder, it would become unsustainable. But if you were to decrease the power on the drive slightly and increase the stroke rate to 27spm you would go faster and the effort level would be the same. The trick comes in knowing how much to decrease the power as you increase the rate, and in having a gradual process through your training to get you to the point you want to be in the race.
You may have seen from my blog that a couple of times over the past year I have gone through a process of increasing rate 2k's. I started off with a 2k restricted to 20spm. I don't have to think too much how much power to put in here because I can pretty much pull as hard as I can (or rather push as hard as I can with my legs...) when I'm only doing a stroke every 3 seconds. But once I have a bench mark pace there I then do the next one (a week or two later) at 22spm, and I know I can go faster. But I decrease the power slightly because I can't still sustain max power on the drive.
Increasing stroke rate has the illusion of feeling harder because our breathing rate is tied to the stroke rate - you'll breathe once, twice, or even 3 times per stroke depending on effort level, but you will always breathe a multple of the rate each minute. So if you increase your 2k rate from 26 to 28spm you will breathe more regularly, and that makes you think you're working harder. It is an illusion though. For the effort level you'll still be taking in and processing the same amount of oxygen.
So how does this all help you? Well, if you are currently in shape to do that 1:46.5 pace (roughly) at 25-26spm, if you maintain 27-28spm you will be able to maintain 1:45.5 pace (roughly) through the 2k for the same real effort level. So the trick here is that if you concentrate on stroke rate during the 2k, and keep it to a minimum of 27spm, but don't put too much power on the drive so don't let yourself go faster that 1:46 pace for the first 1250m or so of the 2k, this will be sustainable and you will be in a good position to push on to a new 2k pb. Of course if you are not currently in shape for 1:46.5 pace at 26spm adjust accordingly from what you can actually do at the moment - maintain 1 to 2spm higher, but don't go faster than 1sec under the pace for that first 1250m (and don't go slower than the pace obviously, because you don't need to as it is more sustainable at this slightly higher rate).
How do you just increase the rate? Simple, at the end of the drive get your hands away quicker and pull yourself back up the slide a little with the foot straps if needed - make your adjustments to stroke rate by speeding up the recovery, not moving faster (and so pulling harder) on the drive. If you find that you're going too fast still, and pulling say 1:45 rather than 1:46, try to decrease the power at the beginning of the drive very slightly - but keep the recovery quicker to keep the rate at 27spm.
Doing it in a very small step like this is the only way it is achieveable - if you tried to go more than 2spm higher it would just be too unusual to you and not sustainable mentally.