Physical Activity Guidelines Advisory Committee Report, 2008

Physical ActivityGuidelines AdvisoryCommittee Report,2008To the Secretary ofHealth and Human ServicesU.S. Department of Health and Human Services

The findings of this report are those of the Physical ActivityGuidelines Advisory Committee. They do not necessarily reflect theviews of the Office of Disease Prevention and Health Promotion or theU.S. Department of Health and Human Services.Suggested citation: Physical Activity Guidelines Advisory Committee. PhysicalActivity Guidelines Advisory Committee Report, 2008. Washington, DC: U.S.Department of Health and Human Services, 2008.

Physical ActivityGuidelines AdvisoryCommittee Report, 2008Prepublication CopyIssued June 2008

DEPARTMENT OF HEALTH AND HUMAN SERVICESOffice of the SecretaryAssistant Secretary for HealthOffice of Public Health and ScienceWashington D.C. 20201May 23, 2008The Honorable Michael O. LeavittSecretary of Health and Human Services200 Independence Avenue, S.W.Washington, D.C. 20201Dear Secretary Leavitt,On behalf of the entire 2008 Physical Activity Guidelines Advisory Committee, we arevery pleased to submit the Physical Activity Guidelines Advisory Committee Report,2008.You charged our committee to “ review existing scientific literature to identify wherethere is sufficient evidence to develop a comprehensive set of specific physical activityrecommendations.” The Committee's report documents scientific background andrationale for the 2008 edition of the Physical Activity Guidelines for Americans. TheCommittee also identified areas where further scientific research is needed.The Committee’s review and deliberations clearly demonstrated that sedentary behaviorconfers substantial health risks throughout the lifespan. The health benefits of beinghabitually physically active appear to apply to all people regardless of age, sex,race/ethnicity, socioeconomic status, and to many people with physical or cognitivedisabilities. The amount and intensity of physical activity needed to achieve many healthbenefits is well within the capacity of most Americans .and can be performed safely. Thisreport provides the scientific basis for these conclusions and the development of federalphysical activity guidelines.For the entire Committee, we want to thank you for the opportunity to support yourPrevention Priority. Over the past twelve months, the Committee members andconsultants worked exceptionally long and hard to conduct the extensive scientific reviewthat made this report possible. Despite this task being added to their usual busy schedules,they met tight deadlines, provided insight and education to one another, and unselfishlyworked to develop a consensus report. Thus, we wish to thank you for assembling acommittee of outstanding professionals who are not only knowledgeable and highlyproductive but also most pleasant in character.U.S. Public Health Service

It is important to emphasize that this report could not have been completed without theoutstanding support of all the HHS staff who assisted us throughout the entire process.We are very grateful for their substantial assistance in developing an extensive electronicsearchable literature database for use by the Committee and for their excellent logisticaland management support in all aspects of the Committee's work. Special recognitiongoes to RADM Penelope Slade Royall and CAPT Richard Troiano of the Office ofDisease Prevention and Health Promotion for their tireless dedication in the coordination,and ultimate completion, of this project. This report greatly benefits from the expertediting provided by Anne Brown Rodgers, who helped us present information that isuseful and readable, and from the careful work of Reba Norman, who ensured thecompleteness and accuracy of the report’s extensive reference lists.Our review documents very strong scientific evidence that physically active people havehigher levels of health-related fitness, a lower risk of developing a number of disablingmedical conditions, and lower rates of various chronic diseases than people who areinactive. Given Americans' low rates of participation in physical activity and highprevalence of chronic diseases and associated disabilities, this report is particularlytimely. It provides the necessary foundation for HHS to proceed to develop PhysicalActivity Guidelines for Americans, 2008 and related policy statements. Strong federalguidelines, policies, and programs regarding physical activity should be an essentialcomponent of any comprehensive disease prevention and health promotion strategy forAmericans. Committee members are committed to the broad dissemination of this reportand the ensuing guidelines. Please do not hesitate to contact us or any of the Committeemembers if we can be of further service.Sincerely,[Signed May 23, 2008]William L. Haskell, Ph.DChair, 2008 Physical Activity Guidelines Advisory CommitteePrevention Research Center, School of Medicine, Stanford University[Signed May 23, 2008]Miriam E. Nelson, Ph.D.Vice-Chair, 2008 Physical Activity Guidelines Advisory CommitteeJohn Hancock Center for Physical Activity and NutritionFriedman School of Nutrition Science and Policy, Tufts University

ContentsPhysical Activity Guidelines Advisory Committee Members .Front Matter-1Part A: Executive Summary.A-1The Physical Activity Guidelines Advisory Committee.A-1Report Contents.A-2Review of the Science on Physical Activity and Health .A-2Research Recommendations.A-10Part B: Introduction.B-1Setting the Stage for Physical Activity Guidelines for Americans.B-1The Physical Activity Guidelines Advisory Committee.B-2A Systematic Review of the Evidence on Physical Activity and Health.B-3Contents and Organization of the Physical Activity Guidelines AdvisoryCommittee Report .B-5Part C: Key Terms .C-1Physical Activity and Exercise .C-1Physical Fitness.C-4Health .C-6Study Design and Measurement .C-6Publication Types .C-7Reference List .C-8Part D: Background .D-1Introduction .D-1Some Issues Regarding Dose Response .D-1Recent Trends in Physical Activity in the United States .D-9Development of Physical Activity Guidelines in the United States.D-17Reference List .D-28Part E: Integration and Summary of the Science .E-1Introduction .E-1Summarizing the Evidence.E-1Integrating the Evidence: Questions and Answers About the HealthBenefits of Physical Activity .E-22Reference List .E-35Part F: Scientific Literature Search Methodology. F-1Background. F-1Conceptual Framework . F-1Physical Activity Guidelines Advisory Committee Reportv

ContentsResearch Questions . F-1Operational Plan . F-3Literature Review. F-4Part G. Section 1: All-Cause Mortality . G1-1Introduction . G1-1Review of the Science . G1-1Overview of Questions Addressed .G1-1Data Sources and Process Used to Answer Questions .G1-1Question 1: Is There an Association Between Physical Activity and All-CauseMortality? If So, What Is the Magnitude of This Association?.G1-2Question 2: What Is the Minimum Amount of Physical Activity Associated WithSignificantly Lower Risk of All-Cause Mortality? .G1-5Question 3: Is There a Dose-Response Relation Between Physical Activity and AllCause Mortality? .G1-14Question 4: What Is the Shape of the Dose-Response Relation Between PhysicalActivity and All-Cause Mortality? .G1-17Question 5: Is the Relation Between Physical Activity and All-Cause MortalityIndependent of Adiposity? .G1-20Overall Summary and Conclusions . G1-21Reference List . G1-23Part G. Section 2: Cardiorespiratory Health. G2-1Introduction . G2-1Review of the Science . G2-1Overview of Questions Addressed .G2-1Data Sources and Process Used To Answer Questions .G2-2Special Considerations and Limitations .G2-3Question 1: What Is the Relationship Between Physical Activity andCardiovascular Morbidity and Mortality? .G2-4Question 2: What Are the Dose-Response Relations Between Physical Activity andCardiovascular Morbidity and Mortality? .G2-12Question 3: What Is the Relationship Between Physical Activity andCerebrovascular Disease and Stroke? .G2-15Question 4: What Is the Relationship Between Physical Activity and PeripheralArterial Disease? .G2-17Question 5: What Is the Relationship Between Physical Activity and Hypertension? .G2-19Question 6. What Is the Relationship Between Physical Activity and AtherogenicDyslipidemia?.G2-21Question 7: What Is the Relationship Between Physical Activity and VascularHealth?.G2-23Question 8: What Is the Relationship Between Physical Activity andCardiorespiratory Fitness?.G2-28Overall Summary and Conclusions . G2-39Physical Activity Guidelines Advisory Committee Reportvi

ContentsResearch Needs. G2-40Reference List . G2-41Part G. Section 3: Metabolic Health. G3-1Introduction . G3-1Review of the Science . G3-2Overview of Questions Asked.G3-2Data Sources and Process Used To Answer Questions .G3-2Question 1. Does Physical Activity Have a Role in Preventing or TreatingMetabolic Syndrome?.G3-3Question 2. Does Physical Activity Have a Role in Preventing and Treating Type 2Diabetes? .G3-9Question 3. Does Physical Activity Have a Role in Reducing Macrovascular Risksin Type 2 Diabetes? .G3-15Question 4. Does Physical Activity Have Benefits for Type 1 Diabetes?.G3-20Question 5. Does Physical Activity Have a Role in Preventing and TreatingDiabetic Microvascular Complications? .G3-22Question 6: Do Physical Activity and Exercise Have a Role In PreventingGestational Diabetes? .G3-28Overall Summary and Conclusions . G3-29Research Needs. G3-29Reference List . G3-30Part G. Section 4: Energy Balance . G4-1Introduction . G4-1Review of the Science . G4-1Overview of Questions Addressed .G4-1Data Sources and Process Used to Answer Questions .G4-1Caveats .G4-2Question 1: How Much Physical Activity Is Needed for Weight Stability andWeight Loss?.G4-2Question 2. How Much Physical Activity Is Needed to Prevent Weight Regain inPreviously Overweight Individuals? .G4-8Question 3. What Is the Effect of Physical Activity on Body CompositionParameters (e.g., Waist Circumference, Intra-Abdominal Fat, AbdominalAdiposity, Total Body Fat) That Are Specifically Related to Metabolic Disorders?.G4-10Question 4: What Effects Do Sex and Age Have on the Role of Physical Activity inEnergy Balance?.G4-13Question 5: How Do the Physical Activity Requirements for Weight MaintenanceDiffer Across Racial/Ethnic and Socioeconomic Groups?.G4-15Overall Summary and Conclusions . G4-19Physical Activity, Weight Stability, and Weight Loss .G4-19Physical Activity and Weight Regain.G4-20Physical Activity and Body Composition Parameters.G4-20Physical Activity Guidelines Advisory Committee Reportvii

ContentsThe Effect of Sex and Age on Physical Activity and Energy Balance.G4-21Physical Activity Requirements Across Race/Ethnicity and Socioeconomic Groups .G4-21Research Needs. G4-21Physical Activity, Weight Stability, and Weight Loss .G4-21Physical Activity and Weight Regain.G4-22Physical Activity and Body Composition Parameters.G4-22The Effect of Sex and Age on Physical Activity and Energy Balance.G4-22Physical Activity Requirements Across Race/Ethnicity and Socioeconomic Groups .G4-22Reference List . G4-23Part G. Section 5: Musculoskeletal Health . G5-1Introduction . G5-1Review of the Science . G5-2Overview of Questions Addressed .

Chair, 2008 Physical Activity Guidelines Advisory Committee Prevention Research Center, School of Medicine, Stanford University [Signed May 23, 2008] Miriam E. Nelson, Ph.D. Vice-Chair, 2008 Physical Activity Guidelines Advisory Committe