Experts are debunking the viral myth that claims running makes your waist bigger. Fitness influencers and social media trolls alike have taken over online discourse with declarations that running as exercise can have an adverse effect to working out by building thicker muscles in the midsection, making the torso more boxy — which would make it more difficult to achieve an hourglass figure . However, science proves that running regularly does not typically cause muscle gain in the midsection. Although running engages your core muscles , including the obliques, the aerobic exercise does not work the muscles in a way that would make them bulky or oversized, according to a medically reviewed article by Healthline . Building a muscle, which is called hypertrophy, often takes specific and consistent work , meaning that it is unlikely that you would grow abdominal and oblique muscles by accident.…