Office workers have something new to worry about, according to a warning that’s gone viral on social media. “Office chair butt” is trending as a side effect of sitting for too many hours, leaving the appearance of a flatter behind. Alissa Mosca, a certified fitness trainer with Planet Fitness in New York, confirmed that “office chair butt” refers to muscle loss due to sitting stagnant in one position and not activating the muscles in the posterior chain (along the back of the body). To combat this, Mosca recommends performing the following simple exercises throughout the day to stimulate muscle activation