Let's make this birthday one to remember.

52 years old (Born on February 14, 1973)

Happy Birthday, Deena Kastor! You're the only person I know who can celebrate another lap around the sun by running 26.2 miles without breaking a sweat—or at least making it look easy. Your bronze medal marathon finish at the 2004 Athens Olympics still inspires us all to lace up our shoes and chase after greatness (though most of us settle for chasing down ice cream trucks).

Here's wishing you endless energy, speedy splits, and plenty more podium finishes ahead—because let's face it: age is just a number when you're outrunning everyone else on race day. Keep setting records—and remember, cake calories don't count if you've run enough marathons!