Find your optimum UT2 spm using Joules per Stroke

[datsch]

If you're doing your long UT2 rows just tapping along at 22 or 24 you may find that each stroke is rather light. Surely all that does is condition your body into pulling light strokes?

Dropping down to 18, 15 or even 10 spm and you can pull hard strokes but keep your heart at 70%. You'll feel like your muscles had a good workout at the same time as conditioning your lungs.

The question is, how low to rate and how hard to pull? That's where Joules per Stroke comes in.

The point of this metric is to help you understand how hard your strokes are.

I made a table where you can read off J/str from your speed and spm. For example the classic 7 min 2k of 1:45 r30 requires 600 J/str.

Look down that 600 column and you will see for example that at rate 15 a speed of 2:13 would require the same strength of pull for each stroke. If you can stay in UT2 at that pace then there you go. If not, experiment to find the rate that suits your UT2 from that 600 column. Then you if you can get used to pulling strokes that are the same strength as your target 2k pace.

You are probably in a different column: I found a video of Ollie Zeidler on his machine doing what appeared to be a steady state (hardly breathing or sweating) of 1:48 r19 which from the table you will see is about 900 J/str. This happens to match a 2k erg test I also found of his which was 1:26 r36 which you will see is also about 900J/str.


The formula I used is:

W = J/s = str/s x J/str

=> J/str = W / str/s

Where W = 2.8 / pace cubed

So if you have 1:45r30 that is s=45, m=1, spm=30

J/Str=(2.8/(((s+(m×60))/500)^3))/(spm/60)


NOTE: Set damper on 1 when trying 10 spm (as the flywheel slows down so much each stroke is almost like a racing start ie tough on your joints at normal damper settings ...)



I'm still not sure how useful this is, but I found it interesting and hope you will too.

[iain]

I know for the purist Joules is a better unit for work per stroke, but for most the "SPI" of Watts /rating (Joules/stroke /60) is simpler to calculate. Your table is a little wide as there is no reason to do a round multiple of 100. It also precludes a gradual increase in work per stroke as we get stronger and our strokes become more consistent.

I think most people would struggle to row at 10SpMin. I have managed 12. Also, how low can you go before the PM stops recording? I thought it kept going for 6S, so a late stroke at 10SpM would see the monitor stop! Also while I can see the point in lowering DF for very low rate rowing, it takes an excellent technique to generate the work at a DF of 70 so I would suggest lowering by a lesser amount.

Finally, there are some great rowers that do not keep work per stroke constant, but increase it with rating. So while I would recommend not allowing it to fall too low (as it means technique errors can become ingrained), keeping it constant does not work for all.

But interesting idea for me as someone who fails to stay in UT2 for longer rows until I get my fitness up to a a level that requires many months of rowing and so have accepted higher HR at R16 or R17 in the early days. Also UT2 without lab testing (and even then it is not completely consistent in the research literature) is very imprecise as the formulas (both % HRmax and %HRR) are indications and do not correspond to a physiological equivalents but vary between individuals.

[datsch]

Yes rate 10 is the lowest you can do, I have done it on a 30r10, but it took some concentration as you are right one cannot err on the low side as it may flash a reading of 9 but generally reads something like 72 which makes sense if as you say the sample time is 6 seconds then you are just peeking into the next sample time as if you had taken a really quick stroke ....

Rate 11 is more practical as you can correct a few strokes of 12 with a few strokes of 10.

Yes, the table is just a sampling of data points to show the trends. For more accuracy I put the formula into excel and made myself a little calculator there.

For example, doing 10m splits at different rates during a 60m UT2 I kept at 70%HR +/-2bpm and found:

Code: Select all

spm  pace	J/str	         pace at 30spm
11     2:22		667		1:42
13     2:17		628		1:44
17     2:14		513		1:51
20	2:13		446		1:56
26	2:14		336		2:08

So if I wanted to go fast then that's rate 20 as 26 did not improve speed. At rate 11 the strokes were perhaps too hard. But rate 13 is where I would sit if I want to pull the same strokes I aim to pull for a 7m 2k.

Of course, there's nothing to say that pulling the same as your 2k stroke strength is a good idea, but I have been trying it for a while and I like it. At least I can see what is going on now with how hard my strokes are at various rates.

[Tsnor]

Yes rate 10 is the lowest you can do, I have done it on a 30r10,

Driving at 10 SPM requires a lot of leg drive/stroke. I've done distance at 12 spm in group workouts, but would never consider that workout anything but a hard workout even with a low HR. 30r10 sounds brutal even if your drag factor is low.

If OP's intent with UT2 was long/slow for pyramid or polarized training then a rate restriction is probably not what they want. The goal of doing long/slow is to AVOID the type of muscle work that requires recovery. If they are wanting a hard workout to gain leg strength then it makes sense.

[jamesg]

Well done. It's the C2 ergs (almost alone) that make the idea of Work per Stroke (Watts/Rating) useable, since they show us our Power output directly, and reasonably accurately.

As we know, Power is Work/Time, and Rating has dimension 1/Time; so
Work/Rating = (Work/Time)/(1/Time) = Work.

Using Watts and Rating, the unit of Work is the Watt-Minute, and 1W-minute = 60W-seconds or 60J.

So keep your Work constant and high at all ratings, via good style, but especially during the low rate ground work, aka UT2 and UT1 (respectively 18-20 and 20-24 when rowing), where endurance is acquired.

All this means in practical terms is use your legs to pull a long hard stroke as to coaches and/or C2 instructions, using the appropriate sequences.

It can be quite fun. I remember our school coach taking us from Hammersmith all the way down to the Houses of Parliament, and back, which none of us had ever seen from the river.

[iain]

The goal of doing long/slow is to AVOID the type of muscle work that requires recovery. If they are wanting a hard workout to gain leg strength then it makes sense.

I have asked about this a few times over the years. Do people agree with the above. It makes sense to me and I personally find that my work per stroke drops when I am tired, but the focus on HR and HRV by the fatness authorities suggested to me that the issue with too many hard sessions was cardiac rather than (skeletal) muscular. Hence the approach of doing low rate SS. Personally I find that this does reduce my pace on subsequent intervals even where HR kept low.

I would reiterate that the stroke certainly feels different at R12 and R30 even where the work per stroke is the same. Essentially the peak force is higher due to the requirement to accelerate a low speed flywheel, not played with DF, but I see how lower DF could be used to keep the flywheel running, but I suspect that the faster average flywheel speed would be a significant difference in the stroke.

My experience in very low rate rowing was to keep HR low when coming back from periods of inactivity as even at R16 my usual stroke would quickly take by HR well into UT1. I concluded that compromising and allowing higher HR and cutting higher intensity workouts until a base had been made seemed to make sense. Also Work per stroke is only close if you have an app measuring number of strokes as there is >7% difference between lowest and highest at R14 per monitor.

[Tsnor]

.. but the focus on HR and HRV by the fatness authorities suggested to me that the issue with too many hard sessions was cardiac rather than (skeletal) muscular. Hence the approach of doing low rate SS.

Autonomic nervous system seems to be the target of the resting HR and HRV measurements rather than pure cardio. Example: https://www.sciencedirect.com/science/a ... 20sessions.

You can lift heavy weights at very low heart rate if you space your workout. But you hit your ANS and require recovery. Keeping a lower HR while lifting (or doing low rate SS) just breaks HR zone as a surrogate for not taxing the fight/flight part of your ANS.

At a guess you can trigger a flight/fight with low SPM rate SS that you would not trigger doing the same workout at higher spm rates and lower muscle force per stroke even at the same split. Sort of like the difference between walking and doing one box jump per minute -- your legs won't feel the same after an hour of each even though your HR is the same.

The ANS focus seems to be in addition to the actual muscle recovery from a workout. (Muscle fiber micro tears, etc.). Overtraining is defined by ANS impact, rather than muscle tissue impact. (example "When overtraining occurs, the autonomic nervous system (ANS) can become significantly imbalanced, often showing a dominance of the sympathetic nervous system (fight-or-flight response), leading to symptoms like fatigue, decreased performance, and mood swings")

Whatever the mechanism, low effort level steady state does seem to trigger adaptation that you don't get with high effort workouts even when researchers try to normalize workout load.

[H2O]

There is a school of thought that you should keep the power per stroke constant across workouts. This does not work for me, as I get back problems doing that. In my workouts the SPI (watt/stroke) varies with UT2 at 7.5 - 8 and faster, shorter pieces 9-9.5, i.e. the opposite of raising the power per stroke when slowing down the stroke rate. After adopting this, my back is feeling much better.

[putridp]

An interesting topic that I have given some thought also. I use watts/spm because it is easy to calculate but it is a mishmash abomination of a unit

This is something I have developed a feeling for, having done millions of metres at rate 20, UT2(ish, perhaps ever so slightly higher, but always at a precise power). I have experimented with reducing the rate whilst maintaining the same precise power (usually starting the session at r20 as a warmup, then r18 for two splits, then r16 for two splits then last split at r20). Despite maintaining the same pace the lower rate work always increases my HR, which then falls again when I increase back to r20 for the last warm-down split. So my feeling is that, whilst the lower rate work is useful muscular training, it can be a bit too intense for LISS.

I save the higher power/spm work for my so called UT1 sessions, which I also do at r20 at a pace that verges towards maximum energy per stroke, usually 8000-10000m maximum at a time, once every 5-7 days.

I'm also experimenting with max energy per stroke work at rate 26-30 2x10:00m/10:00r intervals which feels very different.

My conclusion is that I don't think maximum energy per stroke work is suitable for long duration LISS work - it's too intense. For UT2 work I go the opposite way - reduce the DF slightly to keep fast muscle contraction speed - tapping the wheel along. Muscles 'like' a fast contraction speed - the work is easier to recover from.