Prior to her stint at Bucknell, Mendes served in similar roles at Duke (2020-21) and her alma mater, New Hampshire (2018-20). At Duke, she helped the Blue Devils to the ACC outdoor title. Coaching the jumps, she had four athletes post top four all-time marks in school history and qualify for the NCAA East Preliminary Round. During her time at New Hampshire, her student-athletes set five individual school records and won IC4A and America East titles. Track athletes also won an NCAA title in the women's mile and were All-Americans in three other events.

Mendes spent three seasons as head coach at Merrimack College (2014-17), overseeing all aspects of the program. She assisted in the development of a six-time national champion, 12-time All-American and Olympic Trials runner. Her time there also resulted in All-Americans in the 4x400 relay in two straight seasons, as well as in the heptathlon and decathlon.

Mendes began her career as a graduate assistant coach at Ithaca College, working as head coach of javelin and assistant event coach in the jumps and multi-event groups. She had responsibilities in compliance, eligibility, recruiting, strength and conditioning and meet management.