From flexing in the mirror to constant weigh-ins, the start of a fitness journey comes with high hopes and even higher expectations.

In the push for progress, some end of pushing their bodies too hard—such as skipping rest days or adapting restrictive diets. So what starts as motivation can quickly spiral into patterns that do  more harm than good.

Clinical psychologist, Dr. Jennifer Hartstein of Hartstein Psychological Services, joins NBC News Now’s Mental Health Check to discuss how to know if your healthy habits are more destructive than helpful and how we can maintain a sustainable health practice.

Watch now to learn more.