Chapter 15, Problem 9RQ

Which of the following is NOT part of national guidelines for physical activity for adolescents?

1. a. Engage in at least 60 minutes of strenuous aerobic physical activity at least five days a week.
2. b. Engage in bone-strengthening activities at least three days a week.
3. c. Engage in muscle-strengthening activities at least three days a week.
4. d. Engage in at least 60 minutes of physical activity almost every day.