1. Blair SN, Connely JC: How much physical activity should we do? The case for moderate amounts and intensities of physical activity.Research Quarterly in Exercise and Sports. 1996,67: 93–105.
2. Lee I-M, Paffenbarger RS: Do physical activity and physical fitness avert premature mortality? In Holloszy JO (ed),Exercise and Sport Sciences Reviews (Vol. 24). Baltimore, MD: Williams & Wilkins, 1996, 135–172.
3. Blair SN, Kohl HW, Gordon NF, Paffenbarger RS: How much physical activity is good for health?Annual Review of Public Health. 1992,13: 99–126.
4. American College of Sports Medicine. Position Stand: The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults.Medicine and Science in Sports and Exercise. 1998,30: 975–999.
5. Pate RR, Pratt M, Blair SN, et al: Physical activity and public health: A recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine.Journal of the American Medical Association. 1995,273: 402–407.