If you’ve already blown your resolution to go to the gym more this year, you might blame geography.

The average gym member—among those who actually go—travels just 4 miles to get there, according to Dstillery, a New York-based firm that gathers data for targeted marketing campaigns. The analysis is based on anonymized information from 7.5 million mobile devices taken to a selection of prominent fitness centers between mid-February and mid-March.

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