Does great rowing start with good sleep?

As founders and developers at Quiske we’re naturally interested in any new gadgets that wirelessly can measure and analyze data and especially performance. That’s why we got the Oura rings, which measure and analyze, not rowing, but sleep performance. Also, it’s interesting to us that Oura originated in the city of Oulu, in Northern Finland. As Finns we love comparing our own tech with that created by other Finns 😊

We took the Oura rings into use some months ago and noticed lots of similarities between the rings and our Quiske pods, so we decided to write a review of the rings and also do a comparison of the technology behind the sensors used in the two Finnish startups. Both Oura and Quiske have been around for a while, and both are already selling their 2nd generation of product. Read on also for an assessment on how useful we find the rings for rowers.

Oura in a nutshell: A beautiful ring measuring and analyzing sleeping performance. The data from the ring is uploaded to a phone App and a webportal. The algorithms produce an overall recovery index summarizing your health and fitness status at the start of each day.

Quiske in a nutshell: A sleek and simple pod measuring and analyzing rowing performance. The data from the pod is available instantly for feedback through the phone App but can also be uploaded to a webportal for more detailed analytics. The algorithms produce an overall technique index on indoor rowing performance.

Like Quiske, Oura also comprises a Phone App, a sensor, and cloud analytics. Bluetooth is used for transferring data from the sensor (ring) to the phone. Charging the Oura ring must be done every 3-5 days (Quiske pods needs charging only every 2-4 weeks, but they are not as frequently in use...only while rowing of course). Charging is fast and easy.

The sensors provide accurate data but the plethora of phones supported by the App causes a bit of fragmentation in the quality of the full system. Data can be exported from the cloud for further analysis. The product is easy to use and affordable by ordinary consumers. Where Quiske provides highly specialized analytics on in-stroke data on boat, oar, and seat motion and their synchronization, Oura provides advanced analytics on sleep stages, heart rate variability and the like. The Quiske pods measure data at 100hz, i.e. 100 data points every second. A high data rate is a must since rowing typically is done at 20-30 strokes per minute, and high resolution is needed to be able to analyze the details within each individual stroke. By contrast Oura measures the heart, which beats 40-100 times per minute but stores only the average value every 5 minutes.

It’s a balancing act weighing cost and simplicity versus data accuracy, and deciding what level of accuracy is enough. Oura is a product for consumers. It shouldn’t be confused with a medical level sleep measurement device used in laboratory conditions. That’s yet another similarity between Oura and Quiske. Quiske also envisions creating unobtrusive, simple technology that you can use all the time if you like. The below picture shows comparisons of expensive, complex and highly accurate wired systems versus the simpler wireless Oura and Quiske products (Picture credentials: Polysomnogram: Mikrobitti, Oura, and Kleshnev).

We think it is valuable to produce accurate enough analytics at a price-point that an ordinary consumer can afford, and with a user interface that does not require a degree in engineering.

Often when designing a product you have to do some compromises, and some things are better to measure indirectly, as long as high enough correlation with an absolute laboratory level measurement device can be achieved. Indirect measurements can enable simpler product design at a lower price point as is the case for both Oura and Quiske. This is a key difference between a laboratory or medical device and a consumer product.

Rowing is a full body sport and perhaps physically the most demanding there is. You need knowhow in recovery if you want to perform well in rowing. Exhaustion like no other is easily attainable when rowing at maximum effort. When rowing with correct technique (where you alternate an explosive drive with a relaxed recovery) it is possible to do long sessions on the erg, pushing hard with the legs many thousand times over distances such as the marathon. When regularly rowing at your limit it is really important to let the body recover properly between the hard sessions. That is where accurate recovery measurement becomes valuable. The Oura ring measures recovery mainly through measuring the quality of your sleep but also by combining this with the measured activity level during daytime. The Oura App then gives a recovery index and advice on what type of training is the most beneficial for the body at any particular time.

That's what we intended to find out. We ordered the Oura sizing kit to learn what size rings to get and for which finger: tried rowing on ergs while wearing dummy rings on various different fingers for many long sessions. Choosing the right finger was an easy choice in the end, at least when rowing indoors the thumb is where the ring disturbs the least. You hardly notice it while rowing the erg. In fact you get so used to the ring on the thumb that you only notice it getting in the way when you try opening jars. Also you feel something is missing whenever you're not wearing it (say while you're charging the ring).

It has been interesting to learn more about sleep and recovery and in the process becoming more aware of quality of sleep, and trying to improve it.

The ring measures not only heart rate and variability but also body temperature. Early on in our experiment Oura was able to predict falling ill a day before it actually happened. Minute changes not noticeable by oneself where noticed by the ring even a day before getting fever.

Checking the readiness has also had the effect of encouraging sleeping in whenever possible in order to increase the readiness index, trying to maximize it before starting the day. One in our team found that if possible you should sleep for long enough to get a readiness index of at least 70. No point in getting out of bed before that!

The data provided by Oura can become a bit addictive, and one of us sometimes checks the App in the middle of the night just to learn how much deep vs REM sleep has been earned so far.

Running a startup business and developing new technology is stressful at times. It is easy to get overworked and to start stealing time by depriving oneself of sleep. The Oura ring helps follow readiness and making sure that the theft of sleep time doesn't get out of hand. Lack of sleep can deteriorate your health!

You can already say that wearing the Oura ring has resulted in improved rowing (split times!). This is a direct consequence of starting to follow the sleep advice given by Oura (continuing sleeping until recovery index 70).

On the downside Oura cannot be used for tracking activity when rowing. The ring doesn’t uderstand rowing at all and therefore the activity level is reported wrong: A 1000kcal rowing session is reported as a 80kcal activity.

We've also done some other sports and seems that skiing and other outdoor activities are tracked pretty OK in terms of activity.

At Quiske we do a lot of field testing of our Rowing App using a large range of different phones, both Android and iOS. Since we've got lots of test phones lying around we also did some testing of the Oura App using different phones. The results were similar to that of with the Quiske App: iOS is more mature and has less trouble with the App. There is more fragmentation within the family of Android phones and it is difficult to provide the same experience in all of these. Some Huawei phones refused syncing with the Oura ring at all.

Being an engineer our CTO has a curious mind and loves testing stuff. Bet you always wanted to know whether your thumb or little finger wakes up earlier and which of the fingers dreams more? :-) Our CTO, Pentti that is, used one ring on his thumb and another on his little finger just to measure the reliability of the rings: Does the thumb and the finger measure sleep the same way or does one of the fingers go to sleep or wake up earlier or later? The test results can be read from below and as you can see the results are certainly good enough. Well done there Oura!

Sleep well and you will row better,

Quiske team