I love Car analogies...

Found this and thought it was pretty darn good...

If you have to take advil just to train - Why are you training?

Your torn-up knee is the tire………..

So when you blew out the tire, is it because you ran over nails?

–Contact injury

And when you ran over the nails, is it because you were driving stupid, or safely?
–Poor form

If there were no nails, is it because the tire tread was low?
–Non-painful dysfunction

Did you check the tires’ tread?
–Screening

When was the last time you rotated the tires?
–Program design

Maybe the axle alignment was off on the car?
–Neighboring joints

Is it possible that something in the middle of the chassis threw off the axle, which threw off the alignment, which ran off the tread of the tire?
–Regional Interdependence

When the Check Engine light (pain) comes on, you might be able to make it to the shop.

You might be able to make it another 100, 200, 300 miles.

You might not.

And during the 5 seconds before the Check Engine light came on, do you really think the car was perfect?

http://charlieweingroff.com/2010/03/when-the-pain-check-engine-light-comes-on/