Excessive Larditude - Why it has to go!!

  Nice ride out today.  3 hour fat-burning bimble up the coast (Av HR 116).....

  Had to chuckle whilst cruising past The Swan at Ingham – site of one of my numerous ‘Darwin Award’ moments in years past.  Showing off to all the folks in the beer garden on my Fireblade one evening years ago, I got my knee down on the bend, then a nice sexy wheelie as I got it upright….  quickly followed by massive tank slapper which nearly saw me enter the lounge of the pub through the front windows!  Recovered quite nicely, only to find the mirrors full of jeering blokes making ‘w**ker’ gestures at me as I disappeared up the road.  Ah well, got to laugh.

  Anyway, apart from that I spent most of the time wondering how much quicker a skinnier Andy would go on a pedal bicycle.

  The two variables that determine how fast you go on your bike are:

1. The power you can apply to the pedals
2. The amount of air you have to force out the way as you ride.

  You generally can’t do a lot about your maximum power output – it is a genetic thing that is more or less decided the second you’re conceived.  Training improves it, but you can never improve beyond your genetic limit (not legally anyway!!)

  The second one is incredibly tweakable though, it involves something called your CdA or Drag Area.  The less frontal area you expose to the slipstream, the lower your CdA.  The lower your CdA the less power you need to travel at the same speed.

WARNING: MUCH OF THE FOLLOWING INVOLVES ROUGH BACK-OF-A-FAG-PACKET MATHS!

  A bloke my height weighing 14 stone on a TT bike has a CdA of about 0.256.  If I lost a load of weight (which I am doing!), I’m also reducing my volume and in particular my frontal area.  At 12 stone, my CdA comes down to 0.242.

  Doesn’t look like much but….

  At 28 mph (or about 21:25 for a 10 mile TT), I need to knock out around 305 watts weighing 14 stone.

  To do the same time weighing 12 stone, I only need to bang out 290 watts.  At a very skinny 11 stone, it’s just 280 watts.

  Again, hardly seems worth feeling hungry all the time but….

  My best 25 TT ride last year of 56:40 at 14 stone required about 290 watts.  With the same power at 12 stone (lower CdA), it might have been closer to 55 mins.

  My all time best 10 mile TT ride of 20:48 would have required about 350 watts at 11 stone (which I was in 1996!!).  At 14 stone, I’d need over 400!

  How’s all that for an incentive to lose weight!!!