Which term best describes when someone has mixed feelings about exercise and can see both the pros and cons of participating?

The term that best fits the scenario of having mixed feelings about exercise, perceiving both advantages and disadvantages, is ambivalence. Ambivalence refers to the presence of conflicting emotions or attitudes toward a subject. In the context of exercise, this might manifest as an individual recognizing the health benefits and enjoyment that can come from physical activity, while simultaneously feeling hesitant or resistant due to factors such as time constraints, discomfort, or previous negative experiences.

Commitment typically indicates a strong determination to engage in a behavior, which does not align with the idea of mixed feelings. Motivation involves the drive to pursue a goal or activity but doesn't inherently encompass conflicting perceptions. Detachment suggests a level of disengagement or indifference, which does not capture the essence of having nuanced feelings about exercise. Thus, ambivalence is the most accurate term to describe a state of mixed feelings regarding participation in exercise.