Half Marathon – Holiday Challenge – My own site is smarter than I

So the holiday season is nearing and I decided to restore an old tradition: To row all ranking distances during the holiday break, starting at the longest one, and use the results to get an idea of my current shape.

It is also a good way to get some kilometers in the bank (and raise some money for the Concept2 Holiday Challenge).

I do skip the Full Marathon. My behind would hurt too much. I probably would have to skip trainings after it, and I would have to build an entire day around making time for it.

The morning was a bit busy. I had to go to buy a Christmas tree, then carry it home over 1.5km. I could of course have mounted the roof rack on the car and spared myself the walk, but I don’t like to mount the roof rack, and I don’t mind a little walk.

I paid almost 900 Kc (roughly $45) for the tree, which is ridiculously expensive given that the forests around Brno are full of perfectly fine Christmas trees. Some people solve it like that, they go to the forest to illegally get a tree. Not for me. Growing a Christmas tree of the size I bought takes about 5 years, so imagine how the forest would look if we all took our trees there. Coming to think of it, that price was pretty reasonable.

Then another chore. Got rid of the old water closet, which again I did walking, this time with the wheelbarrow. It’s just a few hundred meters, and this time I wanted to avoid any liquids dripping into my car from the old water closet.

Then it was lunch time, and after lunch I finally sat down to sort out the target pace for my Half Marathon. Here’s what Rowsandall.com said, using the Pro Users OTE Erg CP chart:

Well, that was clearly not useful. I haven’t done any longer hard rows recently, so the extrapolation to 21km is far too optimistic.

So this time I used the CP chart on the free version of Rowsandall.com. The difference with the Pro version is that it only uses the official Concept2 ranking pieces that it finds in your workout history. But this time, that was an advantage, because it finds them automatically, and I could set it to look back a little further:

All right, 1:58.1 based on some pretty old rows. My PB pace is 1:57.5, which I also noted down on the piece of paper that I took with me to the erg basement.

After 5 minutes of warming up, I set off. I wanted to row at 1:58-1:59, but the faster pace came easily, and I soon found myself looking at a 1:22:38 estimate at completion, which is my PB. So I decided to hold 1:57.5 exactly …

I shouldn’t have done that, of course. I had to gradually increase the stroke rate from 24spm to 25spm and eventually to 26spm to hold that pace. With 12km to go I was still optimistic, and I started to play number games. As I passed the 12km to go mark at a time that looked like xx:38, i.e. 38 seconds after the minute, I was going to change that time by 5 seconds every kilometer, to finish exactly at 1:22:38. The idea was to get slightly ahead of that schedule and then push.

With 9km to go the pacing got wobbly, and suddenly I started seeing 2:00, and 2:01.

Time to reconsider.

I would have hated to hand down after rowing for so long, so I decided to back off a bit and aim for 1:58.5 average pace.

I backed off too much, and 1:58.5 average pace came with more than 5km to go. I didn’t have the energy to get back to pulling 1:59.

Only on the final kilometer I started to get back to 1:57, then 1:55 to get the final time under 1:24:00.

Workout Summary - media/20171216-1610470o.csv
--|Total|-Total-|--Avg--|-Avg-|Avg-|-Avg-|-Max-|-Avg
--|Dist-|-Time--|-Pace--|-Pwr-|SPM-|-HR--|-HR--|-DPS
--|21097|83:57.0|01:59.4|205.9|25.1|172.1|180.0|10.0
W-|21097|83:58.0|01:59.4|205.8|25.1|172.0|180.0|10.0
R-|00000|00:00.0|00:00.0|000.0|00.0|000.0|180.0|00.0
Workout Details
#-|SDist|-Split-|-SPace-|-Pwr-|SPM-|AvgHR|MaxHR|DPS-
00|00097|00:22.0|01:53.4|206.2|22.9|099.7|107.0|11.6
01|01000|03:55.8|01:57.9|213.5|23.9|152.7|162.0|10.7
02|01000|03:54.9|01:57.4|216.0|24.2|164.2|166.0|10.6
03|01000|03:54.7|01:57.3|216.7|24.1|169.5|172.0|10.6
04|01000|03:54.6|01:57.3|216.7|24.5|171.4|174.0|10.4
05|01000|03:54.9|01:57.4|216.1|24.8|172.9|174.0|10.3
06|01000|03:54.7|01:57.3|216.7|25.2|172.5|175.0|10.2
07|01000|03:55.3|01:57.7|214.8|25.1|173.7|176.0|10.1
08|01000|03:55.3|01:57.7|214.9|25.3|175.7|178.0|10.1
09|01000|03:55.0|01:57.5|215.9|25.6|176.6|179.0|10.0
10|01000|03:54.9|01:57.4|215.9|25.9|176.7|179.0|09.9
11|01000|03:55.5|01:57.8|214.3|25.8|176.5|178.0|09.9
12|01000|03:55.5|01:57.7|214.4|26.0|177.3|179.0|09.8
13|01000|03:56.8|01:58.4|211.0|26.2|177.2|178.0|09.7
14|01000|04:00.6|02:00.3|201.4|25.7|175.5|177.0|09.7
15|01000|04:05.4|02:02.7|189.5|24.9|173.8|175.0|09.8
16|01000|04:04.5|02:02.3|191.5|24.9|174.0|176.0|09.8
17|01000|04:07.3|02:03.6|185.5|24.5|171.8|174.0|09.9
18|01000|04:05.0|02:02.5|190.2|24.8|172.7|175.0|09.9
19|01000|04:08.6|02:04.3|182.9|24.9|171.9|174.0|09.7
20|01000|04:11.7|02:05.8|175.6|23.9|168.6|170.0|10.0
21|01000|03:56.1|01:58.0|214.2|26.9|174.5|180.0|09.5

Here is an interesting chart of Work per Stroke for the row:

Here are some stats from rowsandall.com:

rPower 207.4W
HR drift 10.66%
rScore 117
TRIMP 244

The rPower value basically tells me that I could have held 207W (as opposed to 206W) by rowing flat, instead of holding 215W and then crashing to 190W. This sounds correct to me.

Here is the updated CP chart after including the HM:

And the updated predictions:

That looks more realistic. I think I am able to hold 211W for the Half Marathon, on a good day. The predicted 10k target is faster than my PB. I think I am going to approach this very conservatively, around 90-95% of the predicted 247W, then see how much I have left in the tank with 2km to go. One has to take into account that the predictions are for a full out effort from a fully rested state.

Still not entirely happy with the predictions. I wondered where rowsandall.com takes the data for rowing at 260W for 15 minutes from? It turns out it found those records in the ANP test, but because of a Painsled bug (in Painsled Beta), it didn’t record the power during the 2 minute rest intervals but kept logging the last power value of the work intervals, so that is an overly optimistic number. When I removed that workout from the Ranking Workouts, I got this:

And the following predictions, which I will use for my Holiday Challenge rows:

It is interesting how big a difference there is between my steady state pace of 2:01-2:02 and this HM pace of 1:59!

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