How long should Jill, age 42, exercise each week for optimal health?

For optimal health, it is recommended that adults engage in at least 150 minutes of moderate-intensity aerobic activity each week. This guideline suggests exercising at least 30 minutes a day for five days a week, which is reflected in the chosen answer. Regular physical activity at this level can help improve cardiovascular health, maintain a healthy weight, and reduce the risk of various chronic diseases.

The approach of exercising for 30 minutes daily is a practical and effective way to incorporate sufficient physical activity into Jill's routine, ensuring she meets the recommended guidelines. This duration promotes not just physical benefits but also mental well-being, contributing to overall health.

The other choices either fall short of or do not adequately align with the recommended levels of activity for optimal health. For example, exercising for a total of only 2 hours per week does not meet the suggested minimum. Similarly, exercising for 20 minutes three times a week lacks the volume needed to achieve the health benefits associated with greater activity levels. In contrast, the selected option combines a reasonable duration with frequency to promote sustained health benefits.