I haven't been properly ill since, oh, November 2008, which is a while, so I guess I had it coming. It being a nasty cold. Not flu. Not plague. Nothing serious. Just a really vicious cold that pinned me to the sofa and stopped me riding my bike for two weeks.
And for once, I should have seen it coming. I say that because I've been using an iphone app called ithlete - it uses a dongle thing that plugs into the ear-phone socket of your phone and a standard Polar HRM belt to measure something called 'HRV - heart-rate variability. Basically you stand there and breathe in and out in time to the animated lungs on the screen for a minute, first thing every morning and it tells you how well recovered your nervous system is based on the difference between your intake and exhalation beats, or the gap between them, or something like that.
It's a bit like taking your resting heart rate in the morning, but a lot more sophisticated. You get a graph with averages over time along with a colour indication of whether you're totally recovered - green - and can kick yourself senseless. Or not quite recovered - orange - and should take things easy that day. Or, surprise, surprise, red, the devil colour, which means chill out, take a rest day, kick back or suffer the consequences...
Given that I can resist anything except the temptation to ride my bike and am quite capable of hammering myself into a deep hole, it makes a lot of sense.
But of course, it won't stop you getting ill. But it will spot the bloody thing coming. Which, if you look at the chart, is pretty much what happened. Two gentle dips followed by a nose dive into the depths of HRV horror that equated to being knocked out cold on the sofa like a dead whale on a beach.
I think it went somewhere down in the 40s, which given that normal is high 70s or more, says it all really. And then you can see it climbing again, until it hit 72 and like a muppet, I went night riding. 'It'll be steady.' Yeah right, ha bloody ha... Too much too soon. The line goes down again and it's taken another five days to get back to where it was. Lesson learned...
Anyway, still learning how the thing works. Obvious stuff - it's intensity that blasts you. You can do six or seven hours steady and as long as you drink, east and sleep properly, it has minimal impact on HRV, but blast out a hill interval session or beast yourself on the turbo and chances are, you'll know all about it next morning.
It seems accurate too. On days when it says I'm good, I'm good, even when I feel bad. And when it says I'm a bit off it, I am, even if I seem to feel okay before heading out. Obviously it's not going to improve fitness in itself, but it's a great way of working out how recovered you are, possibly when you're good to go hard again after illness or lay off and, just as importantly, it gives you objective evidence that you should back off, even if you don't really want to.
I'm not quite sure I like that last bit. I'm not sure I want to be told whether I can go riding or not by my phone and me, being me, I'm sure at some point we'll agree to differ and I'll go off on some epic day regardless and hang the consequences, but for now, it seems like a very good idea.
But for now I'm just about well enough to start feeling twitchy, grumpy and restless, which has got to be good, right? Er...