Messages

1216

Downwind and Racing / Re: Faster is slower and slower is faster

« on: June 21, 2016, 12:28:06 PM »

How can it not benefit us to put a strain gauge on the paddle shaft so that we can understand, day-to-day, how our training is affecting how much power we're able to apply to the paddle.
My two cents.

I completely agree. Having been training with cycle power meters for over 10 years, I'll be the first guy in line to buy a SUP equivalent.

1217

Gear Talk / Re: Scientific Flatwater Board Testing 101

« on: June 21, 2016, 11:46:44 AM »

Your "Test 2" is really interesting. I wonder, though, about the assumption that stroke rate is an adequate proxy for power applied. When you paddle at different speeds to generate the data for that graph, how do you ensure that you're varying only stroke frequency and not force per stroke? I know from technique drills and such that I can change speed independently of stroke rate by altering the reach and power of each stroke.

Yep, you're absolutely right - stroke rate is only part of the power equation and doesn't account for the torque you're producing. Its good practise to use at least two metrics when judging performance (with one acting as the variable and the other as a governor). Power output would be the gold standard but until that arrives its a choice between heart rate or stroke rate. I actually use both in my everyday training but as far as the decision to use it for equipment testing purely came down to stroke rate being the only one you could make statistically viable (to get the right number of runs and not require a longer interval) and secondly that there was published research already (granted in other paddle sports but not SUP) that had reliably indexed stroke rate to work intensity. However, I would openly agree that cadence has limitations when the force data is not able to be recorded. It's also possible that if you tested a board that was beyond your paddling capabilities, this could also sour the results. With all of this in mind, I'd combine tests 1 or 2 but then reinforce that with test 3 (which ignores stroke rate entirely) to likely give you a greater chance you know what is faster.

It's all a work in progress and something I can build on. Thanks for your feedback - its very useful.

1218

Gear Talk / Re: Scientific Flatwater Board Testing 101

« on: June 21, 2016, 08:42:49 AM »

1) Very interesting. Have you performed any formal statistical testing on your data? It would be interesting to see the differences in variance between the two boards.

2) The main flaw in your experimental design of course is that you were not blind to which boards you were on. So this could be a placebo-type effect: you believed that the flat water board would be faster, and so this changed some subtle aspect of your technique or effort, and that is what caused the effect. In medicine, placebo- type effects can often be more substantial than actual treatment effects. It is particularly problematic in this respect that you did not also collect physiological measurements (eg. HR) and perhaps also physical ones using e.g. a strain gauge on the paddle.

But I'm sure that as a scientist you will already appreciate this. Do you have an idea of how you will deal with this criticism from the referees when you submit it to a scientific journal as you mentioned?

3) Of course, what we all want to know now is whether the all-round board is faster in the conditions it was designed (at least partly) for. Measuring performance differences in the sea across a variety of conditions is a substantial scientific challenge, and you may need other ways of doing the comparisons, perhaps.

4) It's great to see someone taking the time and effort to do this. It's extremely difficult to get scientifically convincing results from board comparisons - which is why so few people have tried.

Great reply - thank you. I've numbered your excellent points above and will attempt to address them here:

1) Yes I have. The article I wrote was for a general audience so I left out a considerable amount of statistical material that only would have confused (or frankly just bored) the hell out of most people. I did have extra stats though (such as the coefficient of variation to show how stable the tests and the boards were), t tests (to show that both boards were significantly different from each other) and a few other bits and pieces. My paper will obviously include them but this articles intent was to encourage people that a. kit choice was important and b. you can do it yourself if you make the time. Granted, a lot of this hangs on how important you believe stroke count is but HR is no good in shorter test intervals like this but if you lengthen test intervals out (and Larry Cain has done this) you might be able to use it but then you won't have a decent sample size as it will be too fatiguing. I'm hoping the margin of errors I included allay many of these concerns but for what it is worth, my coefficient of variation (defined as Standard deviation divided by the mean X 100) was no greater than 0-3% on everything (test repeatability and the boards speed and stroke data) bar the slowdown tests (which did push up towards 10 - still not bad but conditions really matter for those).

2) Yes - placebo is a huge issue generally. However, my paper will be focusing on the robustness of the tests themselves rather than worrying about the performance of boards A and B specifically. I would make the case that the statistical analysis and results are strong enough that it would be hard to be affected by placebo - especially the hydrodynamic slow down tests whereby you can't really influence the results anyway as you've just put Archimedes and Newton in the driving seat.

3) Between you, me and the internet, I suspect if you tried these tests in the more typical conditions of a flatwater race (which would have seen a little more chop than I tested in), the gaps between the two boards would come down. Plus I also suspect (and there is research in other sports like K1 to support it) that bodyweight is going to play a huge part in craft performance. It all adds to that people need to test themselves using boards and conditions that suit them. I would also recommend being aware of the test limitations. For example, the slow down tests (test 3 in the article) are fast and easy but used on their own do not consider the nuances of your stroke and if your board is slightly under volume, will perform badly in that one whereas it might do really well in others when the speed (and therefore the resulting lift) might well let it shine.

4) It is hard but not impossible. It's something I'd need to work upto and figure out the right test interval and environment to do so. The margin of errors will increase and its quite likely that as board design becomes a race of diminishing returns, the gains will be swamped by the margin of error. Bearing in mind I've only been paddling a couple of years, I was surprised how statistically repeatably I was able to perform in these trials to start with. I see this as a starting point for other ideas i have in mind.

1219

Downwind and Racing / Re: Faster is slower and slower is faster

« on: June 21, 2016, 07:33:07 AM »

This is where my focus is right now on the bike -- to explore what gains I can make in applied power just by focusing on the efficiency side.

Don't spend too much time on that. The last thing I heard, the science was saying that pedaling in circles was bunkum and that when you look at the applied forces, it really was just a case of who was pushing the cranks downwards the hardest. If you try and smooth it out, you just redistribute what you have, not increase it. However, I've done some work with paralympians and have found that there were gains to be had in the case of major limb to limb imbalances by looking at this.

As for SUP, the prioritization of power over technique (or vice versa) would boil down to how good the paddler actually was in terms of ability and what their level of experience was in my view. Cycling is a lot easier to manage than the highly dynamic nature of board paddling.

1220

Gear Talk / Re: Scientific Flatwater Board Testing 101

« on: June 21, 2016, 07:22:27 AM »

What are you using to count strokes?

I have a Naish Maliko and an NSP Ocean, both in 26 wide on hand. I'd be curious to see the difference between the planing hull design and the pure round hull soft edges hull design. They feel very different.

I used a SUP Speedcoach 2 for this study to provide the stroke data. However, I've also used a Vaaka cadence sensor in the past successfully too.

1221

Gear Talk / Scientific Flatwater Board Testing 101

« on: June 21, 2016, 01:28:55 AM »

Hi guys,

Here's something for you to chew over when you're on your lunchbreak. A roadmap for a bit of scientific testing for race boards.

https://www.supboardermag.com/2016/06/21/board-testing-101-how-to-find-out-what-board-is-fastest-for-yo/

1222

Downwind and Racing / Re: Faster is slower and slower is faster

« on: June 21, 2016, 01:00:12 AM »

Paddling distributes the workload among different physiological systems. Grossly oversimplifying the issue, there's a basic distribution between the muscular system and the cardiovascular system. Running at a higher than optimal cadence will tax the cardiovascular disproportionately relative to the muscular and running a higher than optimal blade size (i.e., gear) will disproportionately stress the muscular system relative to the cardio. In cycling, years of experience have shown that the optimal range for most athletes is in the 90 – 100 RPM.

No, the research says that's the range that riders often fall in but that doesn't mean its optimal. Some of the published literature merely advises about the cost of which cadence you select and there are outliers who have triumphed well outside of that range. 90-100 is generally advised as a good starting point but it will be hard for paddlers to lock their best choice down until there is a power meter on the market.

1223

Downwind and Racing / Re: Faster is slower and slower is faster

« on: June 21, 2016, 12:55:39 AM »

SUP Power meter -

http://kayakpowermeter.com

SUP Ergometer -

https://vasatrainer.com/product/sup-standup-paddle-ergometer/#prettyPhoto

I've been keenly holding my breath but the SUP power meter has been promised to the market numerous times and is now at least 18 months late.

1224

Downwind and Racing / Re: Faster is slower and slower is faster

« on: June 20, 2016, 03:33:07 AM »

I made this point in a recent post in the "Getting pretty good..." thread:

When people get serious about instrumenting SUP boards to try to make them go faster, I expect there will be a cadence for every board/body/speed that has something to do with that kick and a lot to do with limiting blade slip and getting the most energy into forward motion. Blade slip is wasted energy, and generally paddling faster than the board is going guarantees excessive slip. It's a factor other paddlesports watch closely and SUP racers don't watch at all, but there's a strong likelihood that SUP racers will go faster when they paddle slower.

I wonder if anyone is playing around with this. I've been saying that cadence is personal for years, and now I'm thinking I was full of crap.

I would argue that if paddling follows most other sports that require some form of cadence, the right rate is affected by both equipment AND the paddlers physiology. Some guys won't have the developed cardiovascular system to sustain a high cadence any more than some paddlers might not have the torque generation to use a low one. Testing is always needed, not a universal rule.

1225

Gear Talk / Re: 2016 Naish Javelin - 14ft's

« on: June 20, 2016, 03:26:40 AM »

Normal Javelin or Maliko Javelin?

Normal.

1226

Gear Talk / Re: 2016 Naish Javelin - 14ft's

« on: June 20, 2016, 01:06:23 AM »

which one?

The 26 width.

1227

Gear Talk / 2016 Naish Javelin - 14ft's

« on: June 18, 2016, 11:42:18 AM »

Anyone using any of the 2016 14ft javelins ? Any thoughts ? I used one briefly on the sea today and initially liked it but wondered if they were any good on flat waters. Are their features dated ?

1228

Training, Diet, and Fitness / Re: Getting pretty good at racing in about a year - Story, lessons

« on: June 17, 2016, 04:08:53 AM »

Ok, I updated my sup speeds plot. Some of the variation is due to the fact that it's not always the exact same course being run. I.e., in the most recent runs the course has had three 180 degree buoy turns, whereas most of the earlier data is from runs with just one or two buoy turns. Also, some of the runs were races involving drafting, etc. rather than pure time trials. And the was a lot of current in the river from January - March because of El Nino rains.

The dataset sample isn't scientifically that robust but its interesting to see that at first glance, the narrow 22 you have been using isn't much (if any) faster than the 25 you had. Rather than the board, possibly a balancing act too far ?

1229

Gear Talk / Re: twin-fins-or-more-on-a-race-board/so it begins

« on: June 15, 2016, 09:06:27 AM »

It's like anything - perform a robust fin test experiment (and I don't  mean looking at race results or a dataset of just one paddle) and then draw a meaningful conclusion from it.

I am curious to see if two small fins on a flatwater board is faster than one big one. If nothing else, it might allow the manufacturers to drive down width of a board further whilst maintaining stability or improving out and out speed.

1230

SUP General / Re: 12'6 vs 14ft..... again.

« on: June 13, 2016, 12:35:20 AM »

I'm just worried that shit like this is going the make SUP (at least at the pro competitive level) go the way of windsurfing.

The answer is yes. There have been too many other sports that this has happened to and SUP doesn't seem to be showing any signs that would end up a different way.