All you have to do is fail to update your mental map and then persist in following it even when the landscape (or your compass) tries to tell you it's wrong. Edward Cornell once told me, "Whenever you start looking at your map and saying something like, 'Well, that lake could have dried up,' or 'That boulder could have moved,' a red light should go off. You're trying to make reality conform to your expectations rather than seeing what's there. In the sport of orienteering, they call that 'bending the map.' (pp. 164-165)
How often do we ignore aches and pains, 'bending the map' because we want to milk a few more reps, a few more pounds, a few more weeks out of productive training cycle? Sometimes it works out. Sometimes it doesn't.
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