One night this past summer, Frank Gore skipped his second workout. In the context of a future-Hall-of-Fame career founded on famously tireless training, this was a behavioral oddity akin to a drone bee taking five from the hive to tan itself atop a tulip. Where offseason mornings were traditionally spent doing agility drills among a large group of fellow NFL running backs who lived in the area, Gore always strove to separate himself from the pack by hitting up a ballfield near his South Florida home for private sessions around sunset. “That’s the secret weapon,” he says. “It’s the one that gets you over the top, gets you that mindset: ‘I know the next man’s not doing this.