ARLINGTON, Va. -- Thousands of runners are preparing for the SunTrust National Marathon and Half Marathon, and some are going online for their training.

With MapMyRun.com Sam Krehnbrink, of Arlington, plots his training courses and keeps track of his progress as he trains for his first marathon.

Krehnbrink has run 5Ks and 10Ks before, but his cousin, who also uses the Web site, persuaded him to attempt the marathon. MapMyRun.com allows the cousins to track each other's progress.

Krehnbrink also blogs about his training to keep his family aware of how he's doing.

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