Thinking about your health-related behavior that you would like to try to improv

Thinking about your health-related behavior that you would like to try to improve over the semester, what are three physical or mental barriers that may stand in the way of achieving your health-related goal? What is one way to approach each of these barriers so that they do not stand in the way of achieving your health-related goal? (Be sure to cite the scientific evidence that supports this approach!)