Tuesday: 4×15’/4′ (7′ @ 5KP, 8′ @ MP) Marathon Training OTW

Weather:  Lovely.  Sunny.  Temperature was around 60F.  There was a moderate 5-10mph breeze from the WNW.  This was a cross/tail wind heading down river and the cross/head wind going upriver.  (But since I was going to row to power, that didn’t matter!)

Plan:  This was the first time I would be doing one of the Fletcher Marathon Plan sessions on water.  I figured I would need to be a little flexible to make it work.

  • 4 x 15′ / 4′ rest
  • In each 15′ interval
    • 7′ @ 5KP (which is 220 to 235W on the erg)
    • 8′ @ MP (which is 180 to 195W)

As for adaptations.

  • I have about 3000m of river that I can row at high pressure.  This takes me a little bit less than 15 minutes.  I decided to keep the 7′ at 5KP and then just stop short of 8′ if I ran out of river.  This would be more of problem downstream than upstream, both because of current and also the headwind.
  • Power:  I decided to try to row to my erg power specs.  I suspected that this would be really hard, and it was.  After I rowed, I listened to a great podcast about rowing with power meters which said the average difference between erg and OTW powers was in the range of 13% to 16%.  Interesting tidbit.  If I had know that, the targets would have been substantially reduced.

Screen Shot 2017-05-17 at 8.26.07 AM

  • Rate:  I have somewhat arbitrarily decided to match rate to these powers as follows
    • 5KP: 24-26
    • 10KP: 22-24
    • HMP: 20-22
    • MP: 19-21

So, how’d did it go?  It was a really tough, but awesome workout.  I dug very deep to get it done and I definitely faded in the later reps, but I stayed focused and got it done.  From a TRIMP perspective, it was the hardest workout I’ve done since the end of January (HR based TRIMP of 195)


Here’s the interval summary from rowsandall

Workout Summary - media/20170516-135626-SpdCoach 2182533 20170516 0639amo.csv
Workout Details
01|01613|07:00.0|02:10.2|224.6|24.3|164.0|170.0|09.5 - 255-240W
02|01258|05:51.0|02:19.5|190.8|20.1|165.0|170.0|10.7 - 180-195W

So, I tried hard, but I couldn’t hit the erg based targets.  But I was ahead of the 15% derated targets.  For now, I will aim at the top end of the OTW target range.

I’m using the impeller on the speedcoach to try to avoid stream effects on the live pace display.  I’ve tried to calibrate the impeller input, but based on a comparison of the speedcoach and GPS data today, I think my cal factor might be a bit slow.

Workout Summary - media/20170517-123357-87478o.csv
Workout Details

I compared the paces.


So, based on this data, I think my impeller is reading about 4.5 seconds slow.

This row gave me a treasure trove of data to look at the state of my rowing technique.  Here is a gallery of the plots that I did.

  • Power and pace vs stroke rate:  pace is bimodal due to headwind.  Power is not.  Pretty wide spread because of the way I started faster and faded
  • Effective length vs stroke rate:  Slightly longer at r24 than at r20.  This is pretty consistent with what I’ve read in Kleshnev and other places
  • Wash:  Wash got a little bit worse as I got more tired, but I think it is pretty good.  I guess my finishes are in OK shape.
  • Slip:  Lower slip values at r24.  This is where the better length is coming from.  I am attacking the catch with more enthusiasm at the higher stroke rate.  Not sure if that is a good thing or a bad thing.  I need to figure out if it is resulting in a more fficient generation of boat speed relative to the effort (power).  That will be a longer term project.
  • Catch:  consistent.  A little degradation in the last interval.  Certainly more variation from stroke to stroke.
  • Finish:  Better and more consistent at r24.  You can see how I was really struggling at the beginning of each of the r20 sections.  I dug a deep hole with the higher power segments, and when I gear shifted I struggled to take full strokes.
  • Effective length vs time:  You can see the effect of me gasping for breath at the beginning of the MP sections, especially in the later intervals
  • Work per stroke vs time:   I filtered the data to do two plots.  One for r24 and the other for r20. Very clear reduction in r24 WPS over the workout.  I was rowing to lower power and slightly higher rate.   This is physiological, not technique.  In the r20 sections, you can see me digging out of the lactate hole through each of them and finishing stronger.


Now I am flying out to LAX.  I will take today as a rest day.  Tomorrow morning, I have two possible plans.  If I stay over I’m planning to visit Crossfit Anaerobic in Irvine and do this session…

M2 4 x 20′ / 2′ MP, 10KP, HMP, MP 90.0% (167)

I might take the red eye home.  If I do that, I have my rowing gear in my car and my plan would be to stop and row on my way home from the airport.  The plan would then be to do a version of this OTW.  Each section would probably be closer to 15 minutes.

Wednesday: 15km OTW

Weather:  Cold and misty.  Around 37F.  Wind 3-5 mph from the North.  This was a head wind heading down river and a bit of a tail wind going up river.

Plan for the workout was the same as Monday.  Focus on technique and learn how to incorporate feedback from the EmPower oarlock into really focused practice.

I also  wanted to experiment with the idea of using my phone with RIM to complement the speedcoach display.  So, I hooked up my HR monitor to my phone instead of the speedcoach.

I spent the whole workout looking at the work per stroke screen and trying to keep my drive length greater than 100 degrees.

It was another really joyful row.  Up and down the river a couple of times focusing on form versus pace.  By having my HR on the RIM display, I was able to watch and try to keep the intensity in the aerobic zone.  I let it go a bit higher if I was comfortable and working on technique.

So, now I had one set of data on the phone and one set of data on the speedcoach.  How do I put them together.  Well, it turns out that rowsandall.com has a feature called “Sensor Fusion”.  This feature let’s you take specific fields from two different data sources, align the start points manually, and create a workout entry that combines the two.  In the plot below, the SPM comes from RIM, and so it goes to the very beginning.  The pace and power comes from the speedcoach, and I started that about 6 minutes into the row.


There are some interesting features in the power part of the summary plot.  The blue bars showing the higher power levels are when I needed to apply a lot of port pressure to go around a turn in the river.

The pace shows the effect of the current.  Today is was a good 10 seconds difference on pace.  Notice how consistent the power is, even though the pace is very different.


It’s going to take a while to really know how to use all the data I’m getting.  Here’s a sampler.  A few thoughts..

  • Power is lower than I was expecting at 154W avg.
  • Finish angle was consistent, but Wash got progressively worse
  • Catch and slip were remarkably consistent
  • Effectively drive length is a short 80 degrees.  This is probably driven mostly by critical body dimensions (like my stubby legs), but it will pay dividends if I can figure out how to get a longer drive angle and less wash at the end.

I finished up and put away my boat.  When I looked in the car window at my reflection, I could see that a nice layer of dew had formed on my hat because it was so misty.

2017-04-05 08.03.49

Today (Thursday), I didn’t have a chance to workout.  I caught the morning flight from Boston to San Diego, had a few customer meetings, and now I’m on  the red eye heading home.  I’m going to pick up my boat on my way home from the airport and I might be able to go for a row in the afternoon.  Otherwise, it’ll be another easy hour on the erg.


Monday: Back On The Water!!!! 15km

Weather:  Cold and Sunny.  About 35F.  Basically no wind.  A beautiful morning.

Today was all about just getting back in the boat and trying out my new toys.

New iPhone, case and mount –> running RIM

New Speedcoach GPS (Model 2)

New EmPower Oarlock

The iphone case and mount worked great.  Much more rigid than the mount that I was using last year (and considerably cheaper).   I got them from Quad Lock.

The empower oarlock and HR monitor paired with the Speedcoach very easily.  I had done the angle calibration on Sunday.  The force calibration was easy and quick.

I was off the dock within 20 minutes of getting there.  The river is really high right now.  Right up to the top of the dock, and the current is visibly faster than normal.  I was the only person out on Monday morning.  I had a beautiful morning all to myself.

Our population of swans seems bigger this year.  There was a pretty good number of cygnets last summer.  I think they’ve grown up and returned.  Pretty to look at, but additional obstacles to row around.

I did my normal row, about 15km.  Starting at the docks, I row 4km downstream.  The first km is winding and slow.  After that, it’s lovely flat water and mostly straight for 2km.  Then I go under a narrow bridge and the last km is out across a small basin before the Moody Street Dam.  It’s a beautiful row and I was so happy to be back outside, enjoying the morning.

After I turn at the dam, I row back upstream.  This time of year, I row up into a long cove instead of completely retracing my steps.  There are some nice houses along the cove, and I get a little more distance.  It’s about 3km from the dam to the end of the cove.  Then I spin, and head back down river to the dam.  Finally, I turn back up river and row the 4km back to the dock.

The first and last km where it’s winding I think of as the warmup and cool down.

Now, for the toys.  I loved rowing with the EmPower Oarlock.  I tried out all the skill screens.  There are screen to show catch and with slip, finish angle with wash, power, and work per stroke.  I used one screen for each of the 3km sections.  Unfortunately, I was enjoying the row so much that I didn’t notice that I had forgotten to start the speedcoach.  The way the speedcoach works, it gives you a live screen, but just doesn’t accumulate data if it isn’t started.  Of course it does say “stop” right in the middle of the screen, but I just didn’t notice that.  I hope I don’t make the mistake again, I’m sure I will.

Of course, since I am obsessive enough about data that I run redundant systems, I had the whole row recorded with the Rowing in Motion app on my phone.

The skill screens on the Speedcoach are great, but I was bothered that I wasn’t able to keep an eye on my Heart Rate while I had those displays up.  I know from reading the NK materials that this was a concious choice to limit the chances of information overload, but I find it pretty easy to focus in on on number in a display and only look at other ones every few strokes.  I wish that HR and SPM were visible on the skill screens.

But, I have a solution to my problem.  Since I am running RIM anyway, I can get that info from my phone while I use the speedcoach for technique feedback.  The great part about that is rowsandall provides a cool feature to let me smoosh the data from RIM and Speecoach together before I analyze it.  (More about that in my next post).

Based on that conclusion, I will most likely pair my HR monitor to my phone and use the RIM display to show pace, HR, SPM and time.  I’ll stick to skill screens on the speed coach, unless I’m doing a workout where I want faster pace feedback, like short sprints.


You can see effect of the current on pace.  It was about 10 second delta

Here’s a view of just the speedcoach data for the last 30 minutes of the row.4-3c.png

And here’s a stroke profile for the section from 2000m to 2600m


I need to double check the angle calibration before I draw any conclusions from this.

I did a quick very of effective drive length and work per stroke to get a baseline.


The effective drive length has got me worried, so I wanted to compare it to total length.


I think I have some work to do to get a longer drive.

I also just looked a power for this chunk.


It’s lower than I would have expected. I guess I have some work to do on strength and fitness too!

So.  Much.  Data.  🙂