Louis Serafini

Lou is a Boston-based, self-taught running coach with over 15 years of experience working with athletes of all ability levels — from first-time marathoners to elite competitors. A 3:59 miler and 2:14 marathoner, Lou has qualified for the U.S. Olympic Marathon Trials four times, giving him a deep, firsthand understanding of what it takes to train at the highest level. Lou's coaching philosophy is rooted in simplicity and consistency. Having built his own training knowledge from the ground up rather than through a traditional certification pipeline, he brings a practical, athlete-first approach that prioritizes honest communication, smart progression, and long-term development over quick fixes. He's coached runners through PRs at every distance, from the 800m to the marathon, and believes that the fundamentals — aerobic development, consistency, and speed — are the keys to improving and getting faster. When he's not coaching or running, Lou lives in the Cambridge area with his partner and two dogs, and stays deeply embedded in the local running community he's helped build over the past decade and a half.