iPhone (or Android) Paddle Coach

iPhone mounted on Kahele for real time analysis using app Rowing Coach 4.0

iPhone mounted on Kahele for real time analysis using app Rowing Coach 4.0

A coach recently suggested I put a speedometer on my OC1 as the next step in my training. The price point of the NK Coach gadgets is a budget breaker, and I had to wonder what would I really get out of this data? At first I thought I would just build my own, since I’m a small electronics geek. I knew also that all of this capacity is built into our smart watches and cell phones. It just seemed that no one had written an app for paddlers that would solve the problem, and I have a huge iPhone 7 plus I don’t carry on the boat. Or was it the way I was looking to solve the issue the real problem? Once I entered the keyword “stroke” into the Apple app store, everything changed. There are stroke counters there, but they are geared for rowers. Aha!

I already have an accelerometer app on my iPhone, which gives you a visual graph showing how, in x,y and z coordinates, you move your phone around. I own accelerometers that cost about $5, and I can program them to recognize a specific motion in x,y and z coordinates. This is how your watch knows the difference between a step and a stroke. So, the question then was, just how differently were these rowing coach stroke counters calibrated for the accelerometer in my cellphone? Would they recognize a paddle stroke? No way to know other than to give them a try.

I paid $8 US for Rowing Coach 4.0, put it on my Apple watch and went out for a paddle. I was so confused that I just ended up deleting it and trying another app, named Rowing Coach. This one turns on water lock, and I even tried running it in the background with Waterspeed in the foreground. However, the stroke count was so off, the data was just useless.

I’m not sure why I decided to go back to Row Coach 4.0 and give it another try, but I did - with one major difference. I installed it on an old iPhone that has no cellular. Was it possible I could still use the iPhone as a computer, could I access the GPS and accelerometer chips and get the app to perform? I turned it on and went for a walk, giving it a little shake as if it were a paddling stroke. Sure enough, it worked. And what was really great is it had a high contrast white background with black lettering - very close to what you see on electronics used in direct sunlight conditions, like my VHF radio.

The next step was to mount the iPhone to my canoe. I put it inside a Pelican box, added some cushion with a foam block and a rubber thing under it, and went out for a paddle. Let’s just say, I did not understand the app when I first tried it. This is a REAL TIME ANALYSIS APP that works like the display on a C2 Rower. It expects that you are working in 500 meter sessions. It is very well-tuned and picks up every single stroke accurately. As quickly as it can track the satellites and do the math, it is telling you your stroke length - your distance per stroke or glide. Within minutes I had real time data of how far I was moving my canoe against the wind, with the wind, across the wind. If you stop paddling for several seconds, it will restart at 0.00. This is realize is part of its real time functioning.


So how did I go from wanting a speedometer to wanting to know distance per stroke? I came across a podcast on Nick Murray’s TC Surfski site, in which Michele Eray discusses coaching and using the Vaaka cadence sensor for feedback on stroke performance. Speed, she says, is not meaningful. It’s how you move the surfski stroke by stroke, your cadence. Well, I’ve certainly seen long slow strokers cross the finish line ahead of rapid paddlers (and vice versa), and I decided that she’s an Olympian she probably knows what she’s talking about.

Row Coach 4.0, attached to your vessel (I’m sure it works for surfski, SUP, bathtub, etc.) is a great real time tool for power and cadence analysis. If you click on the little settings wheel in the upper left corner, you will go to a menu where “RECORDING” is listed. This is where a stroke by stroke log is kept, and you can scroll through it to get an idea of where you are at. It is very extensive. I played around with it running for 2 hours, had plenty of battery left and am a better paddler for it. I was even able to see just how far a well-time stroke could get me on some good downwind bumps. So, this is really a versatile tool.

Basically, if you want to go out and use 500 meter bursts for training, this is a great tool for setting a race pace. The reason you would put it on your watch is so that a coach watching your progress on a linked iPhone would get the data from the watch. So, basically, I was just clueless.

You can put this app on any current iPhone or Android, and if speed is all you are after displayed on your phone, you can use Waterspeed for that. I was a little clueless about what I could do with a cellphone as display. But on the other hand, of all the paddlers I know, I’ve never seen anyone using a smartphone as a real time display. If you have an old one in a drawer like I did, put it to use!

This app is smart enough to ask you how much you weigh and the weight of your boat, so it can filter out noise or be used on a heavier boat. It also has a real time GPS page with speed, but this display is rather small on the phone. Plenty to play around with.

A quick philosophical point: use data analysis to fine tune your technique, then put it away. There is so much data coming so fast it’s hard to keep your eye on the waves, and after all, it’s the waves that we’re after. See you on the water.