02/24/2012 11:30 am ET

Running On Empty: One Runner's Firsthand Account Of Disordered Eating

The scale reads 158.2. Up a pound from yesterday. And after a run, no less. Son of a bitch. I step into the shower and scrub the dirt off my calves and ankles, the sweat from my face, from behind my ears. I know it's irrational, but a germ of a thought percolates in my brain: Maybe, just maybe, collectively erasing these micrograms from my skin will bring me into 157-pound territory. I towel off and step back on the scale. I'm running my first marathon next month, and at five-foot-eight, I want to toe the line at 155 pounds, preferably 153. I'm hellbent on breaking four hours. I look down. Dammit. Same unfeeling numbers. Okay, scratch tomorrow's rest day. Later, as I pack my lunch -- debating between one or two mini wheat bagels to go with a wedge of light cream cheese and an apple -- I pray it's nobody's birthday at the office today. Cake is the devil.

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