Measuring the market's beating heart?

Following Canalys' market size predictions for smart watches and activity bands, rival ABI Research is back in the news.

It's now pulling numbers about the market size for heart rate monitors out of the air (surely using complex estimative algorithms? - Ed).

It reckons 12 million devices with the functionality shipped in 2013.

This seems rather high, given that few of the wearable fitness devices in 2013 could directly measure heart rate. There's the Withings Pulse and Basis B1 watch, but the main type of devices that measure heart rate are the dedicated chest straps you get from the likes of Polar and Beurer.

Personally, I'd be surprised if 12 million of those were sold in 2013 - although I bought two during the period - and anyway, they're not really devices. More like peripherals.

"The market for wearable computing devices is driven by a growing range of wireless connected wearable sports, fitness and wellbeing devices," says Jonathan Collins, principal analyst at ABI Research.

"Heart rate and activity monitors will outpace shipments of smart watches and glasses for some years to come and they will also provide the essential foundation for the development of the broader wearable market."

That said, I think heart rate (like blood pressure) is an important element of the qualified self, even if I'm not convinced that devices like the Basis B1, Adidas miCoach Smart Run watch and forthcoming Atlas band are very accurate.

Of course, Apple might change all that...

D.I.Y. Data: Checking my vital signs

Following the self-destruction of my Up band, and general moaning about the lack of open source data, I've come up with a solution.

Well, a solution of sorts. I've started manually tracking myself.

Luckily, we had a blood pressure monitor in a back cupboard and that's the core of my new regime.

When I get up, I weight myself and check my blood pressure and heart rate. That's manually entered into a spreadsheet, and I drop the numbers into a simple graph (below).

It's not rocket science, but checking these vital signs at roughly the same time every day (always before eating) should provide consistent results.

More generally, checking our vital signs is a step beyond the sport and health trackers because you certainly can't take a blood pressure reading without a proper sleeve attachment. However, the monitors themselves aren't expensive and some manufacturers of other health equipment such as Beurer and Withings do sub-£30/$50 examples.

Equally, measuring your blood pressure is medically more important than factors such as heartrate, sleeping patterns or even weight. There's a reason they call high blood pressure the 'silent killer'.

Of course, it is related to metrics such as weight, diet and general fitness, but as you can see, at the start of the process, my blood pressure was rather high.

I've since made some lifestyle tweaks and am happy to see it dropping towards the standard '120 over 80', although I'm sure there's a large psychological element in this. My lifestyle changes are not so radical that it would have had this impact so quickly.

Anyhow, what's more significant for me is not just rely on what my sensors are recording. Sure, that's useful but just because we're measuring something doesn't mean it's important. 

The danger of data

While I think we can find out many interesting patterns by recording our data, one danger is that the data itself (or parts of the data) becomes more important than the activity we're looking to track.

It's something I'm coming to terms with respect to my use of my Beurer heartrate monitor.

When I first used it, I was surprised to  see that my peak heart rate - during a game of hockey - was recorded as 196 beats per minutes.

As we all know, the rule of thumb is that your maximum bpm is 220-your age. Believe me, I'm not 24 - not even close. Of course, such rules are just an average. There are plenty of known limitations.

The first time I used the monitor, it was a hot day, and I knew I'd worked hard during the game. But as I've used the monitor in various games since - hockey and football - I've recorded similar peaks. And the monitor seems to be working fine, because during 5 and 10 km runs, it's recording much lower peaks of around 180 bpm.

Yet now when I play sports, I'm increasingly noticing that I'm viewing my performance on my peak bpm, rather than my average bpm; a more useful longterm measure and something that the watch also records.

So I think it's time to stop using a heart rate monitor for team sports games. Maybe I'll have another look at Adidas miCoach - something I've already used with some success for hockey and football, despite the hardware's lack of mechanical robustness. Hopefully that's something which has been improved since version 1.0.