I am particularly impressed to read about the England Rugby team's latest 'secret weapon' in he current issue of The Week Magazine.

The last paragraph explains that the team took to the field at Twickenham last week (where they stuffed Australia 35-18) wearing a GPS-enabled heart rate monitor. The device is reportedly the size of a watch and was placed in a padded pocket within each player's shirt.

The team management were then able to monitor player performance including distance run, speed and, I imagine, some kind of 'stress' indicator based on heart rate/exertion. The information is apparently able to be viewed on team iPads, iPhones and laptops in real time.

That is pretty smart. Indeed I wonder if these kinds of metrics are going to become widespread shortly. Being able to effectively judge the current exertion rates of your squad may change how managers decide strategy, position changes and substitution.

How long before every one of the Manchester United home crowd is monitoring Wayne Rooney's high heart rate (and sluggish performance) and looking to manager Alex Ferguson for an early substitution?

I'm not sure sports teams would want this kind of live biometrics and performance metrics available to all and sundry, least of all their current competitors. But it would be a smart way to influence the device purchase choice of the millions of football fans if the data was available only to, say, Windows Phone users. The popularity of Formula 1's mountain of live statistics available across multiple mediums points the way.

(Written at about 20,000ft between London Heathrow and Berlin Tegel airports)