We checked in on the ultrarunner midway through her attempt at a women's world record.
Do you know the difference between fast-twitch and slow-twitch?
Bethany Alvarez was busy studying for the SAT, applying to college and being a teenager...oh yeah, and training for a marathon.
Despite her diagnosis of multiple sclerosis in 2006, Cheryl has run more than 30 marathons.
America's greatest marathoner chases significant, meaningful digits (aka race times) for very specific reasons.