I wish I’d been smart enough to work this out before the ITBS kicked in. Of course, it probably falls into the ‘spurious correlation’ category of statistical analysis, but there’s some sensible logic behind it… specifically:

That’s reasonable, of course: as you train, your speed increases each time you run, however your body cumulates fatigue. Consequently, your performance will level off at a certain point in training, then your running times will once again increase. Panicked at losing speed, you will push yourself too hard and wind up injured.

It’s an interesting post. Not everyone will be up to the maths (I can’t be bothered, and its too late for me!), and common sense may work as well, but its interesting reading for runners. Via the ever-useful Lifehacker.