2008 Physical Activity Guidelines for Americans

1. Janet E. Fulton, PhD David M. Buchner, MD, MPH Division of Nutrition, Physical Activity and Obesity Centers for Disease Control and Prevention 2008 Physical Activity Guidelines for Americans

2. DNPAO Teleconference Goals Be familiar with the 2008 Physical Activity Guidelines for Americans Understand the role of State Health Departments in promoting the Guidelines

3. Overview Background and development The Guidelines Children and adolescents Adults Older adults Special considerations Promotion of the Guidelines CDC’s role State’s role

4. The Federal Government published comprehensive Physical Activity Guidelines for Americans for the first time in 2008 2008 Physical Activity Guidelinesfor Americans “ ”

5. Developing the Guidelines Processes Products Processes Products Proposal to HHS for New PA Guidelines IOM Workshop (Oct 2006) Secretary Leavitt Announcement: HHS to release PA guidelines in Oct 2008 Form HHS Leadership Team: HHS, ODPHP, PCPFS, CDC Searchable Data Base (now public access) Systematic Evidence Review (CDC)

6. Developing the Guidelines (2) Products Processes 650+ page report summarizing the science PA Guidelines Advisory Committee (FACA) Translate for Practitioners PA Guidelines Writing Group (HHS) 2008 Physical Activity Guidelines For Americans Communications Workgroup (HHS) Translate for Public Dissemination plan, materials for public, materials for partners, logo & key messages Launch “Team” (HHS Staff and Partners) Evaluation (DNPAO)

7. What Is New About the Guidelines? First major science review in more than a decade Provides guidance for many groups: Children and adolescents Healthy adults and older adults Pregnant and postpartum women People with disabilities and chronic conditions Provides guidance for non-aerobic activities: Muscle and bone-strengthening, flexibility, balance Identifies health benefits, amounts necessary to get the benefits, and provides bridge to PA promotion Specifies a total amount of activity per week People can design own way to meet Guidelines

8. What May Surprise You About the Guidelines • More choices on frequency (days / week) • Can use either absolute or relative aerobic intensity • Muscle-strengthening activities strongly endorsed, but not some features of typical training programs (e.g, no requirement for non-consecutive days) • Flexibility activities, and warm-up / cool down activities are acceptable, but not a guideline • Separate guideline to avoid inactivity

9. More Surprises About the Guidelines • Revised guidelines on PA and healthy weight; PAG did not repeat: • “60 minute guideline” for prevention of wt gain and “90 minute guideline” for wt regain • Obesity / healthy wt regarded as one of many chronic conditions where “more is better” • Clear statement that healthy children and adults do not need “physician approval” or consultation prior to engaging in PA • Substantial attention to preventing adverse events

10. General Concepts

11. Volume is Major Determinant of Health Benefits • Volume • Total weekly amount of PA • Product of: • frequency (episodes / week) • intensity (level of effort / episode) • light, moderate, vigorous; METs • duration (time / episode) • Volume more important to health benefits than any single component

12. Understanding Aerobic Intensity • Common area of confusion, and concepts difficult to communicate to public • Two measures of intensity: • Absolute intensity = rate of energy expenditure during activity typically measured in METs • Commonly measured in METs where: • 1 MET = energy expenditure at rest • Relative intensity = level of effort compared to an individual’s level of fitness • A person can use EITHER measure to determine if they are meeting the guidelines • See appendix for detailed explanation why

13. Absolute Intensity • Activities are classified into light-, moderate-, or vigorous-intensity based on amount of energy expended/minute (METs) • Moderate = 3.0 to 5.9 METs • Vigorous = 6.0+ METs • One needs to look up the intensity of an activity (see tables in guidelines) • Brisk walk = moderate; Jog/run = vigorous • Activities can be either light, moderate, or vigorous based on (usually) speed of doing them • Leisurely walk = light intensity • Brisk walk = moderate intensity • Race-walking = vigorous intensity

14. Relative Intensity • Effort required relative to person’s fitness level • Guidelines use 0-10 scale to communicate relative intensity, where: • Sitting is 0 • Highest level of effort possible is 10 • Moderate-intensity activity = a 5 or 6 • Vigorous-intensity activity = a 7 or 8. • To help communication, the PA guidelines endorsed the “talk test” and advises people to pay attention to heart rate and breathing • Moderate-intensity = can talk without pausing, but cannot sing • Vigorous-intensity = cannot say more than a few words without pausing for breath • Relative intensity of a brisk walkdepends on fitness and can be: • light-intensity for elite athletes • moderate-intensity for recreational walkers • high intensity for inactive middle-aged adults • Impossible for near-frail older adults

15. What are the Guidelines? 15

16. Health Benefits

17. Health Benefits of Physical Activity: Strong Evidence • Lower risk of: • Early death • Coronary heart disease, stroke • High blood pressure, adverse lipid profile • Type 2 diabetes • Cancers: Colon and Breast • Prevention of weight gain • Weight loss (with reduction of caloric intake) • Prevention of falls • Depression, cognitive function (older adults)

18. Children and AdolescentsAges 6-17

19. Children and Adolescents (ages 6-17) 60 or more minutes of physical activity daily Aerobic: Most of the 60 or more minutes per day should be either moderate- or vigorous-intensity aerobic physical activity. Include vigorous-intensity physical activity at least 3 days per week. Muscle-strengthening: Include muscle-strengthening physical activity on at least 3 days of the week, as part of the 60 or more minutes. Bone-strengthening: Include bone-strengthening physical activity on at least 3 days of the week, as part of the 60 or more minutes. Encourage participation in physical activities that are: Age appropriate, enjoyable, and offer variety

20. Comments onChild and Adolescent Guidelines • As opposed to adults, no choice on frequency • Daily PA required • Unstructured play can meet guidelines • Requires some vigorous intensity activity • Moderate-intensity activity only not sufficient • Insufficient data to specify exact amounts/ranges of vigorous aerobic, muscle strengthening, and bone strengthening • Challenge to track youth that meet this guideline

21. Comments onChild and Adolescent Guidelines (2) • As children age, structured activity becomes more appropriate way to get PA • Emphasis on variety of activity reflects attention to: • Importance of skill development • Reducing overuse injuries • Fun / adherence • First chapter of PAG affirms importance of PA to children younger than age 6; science not reviewed for ages 0-6 years • PA recommended for children with disabilities

22. Physical Activity Strategies for Youth • Provide time for structured and unstructured activity during and outside school • Recess, PA breaks, PE, After-school programs • Positive feedback and good role modeling • Praise, rewards, encouragement • Do NOT use activity as punishment • Help young people learn skills • Understand intensity, set goals, protective gear • Promote lifetime activities • Allow variety of activities

23. AdultsAges 18-64

24. 4 Key Adult Guidelines • Avoid inactivity • Substantial health benefits from medium amounts of aerobic activity • More health benefits from high amounts of aerobic activity • Muscle-strengthening activities provide additional health benefits

25. Inactivity • “All adults should avoid inactivity. Some physical activity is better than none, and adults who participate in any amount of physical activity gain some health benefits.”

26. Comments on Inactivity Guideline • The dose response relationship between amount of PA and health benefits => • Low amounts of PA have some health benefits • PAGAC report • 60 minutes/week of relatively moderate intensity PA causes small increases in fitness and lower risk all –cause mortality and CAD. • No evidence of threshold level of PA, below which there are no benefits • Don’t allow this inactivity guideline to undermine the message of the key 150 minute guideline.

27. Substantial Health Benefits Guideline • “For substantial health benefits, adults should do: • at least 150 minutes (2.5 hours) a week of moderate-intensity aerobic activity OR • 75 minutes (1.25 hours) a week of vigorous-intensity aerobic physical activity OR • an equivalent combination of moderate- and vigorous-intensity aerobic activity.” • “Aerobic activity should be performed • in episodes of at least 10 minutes, • And preferably, it should be spread throughout the week.”

28. Comments on 150 Minute Guideline (1) • Minimum intensity = moderate • A person who does only light-intensity activity is regarded to be inactive • If do moderate intensity, need at least 150 minutes/week • Minimum duration = 10 minutes • Episodes of 10 minutes or longer improve aerobic fitness and some biomarkers • Total PA in most observational studies is usually accumulated from activities of varying, but unknown, duration • Unknown (and difficult to study) if health benefits of one 30 minute bout are exactly the same as from three 10 minute bouts.

29. Comments on 150 Minute Guideline (2) • Minimum Frequency • There is insufficient evidence to say that the health benefits are any different from moderate-intensity PA: • 50 minutes/day on 3 days/week = 150 minutes • 30 minutes/day on 5 days/week = 150 minutes • The 30 minute/day x 5 days/week guideline is too specific, but still OK to follow • Guidelines suggest 3 days/week as minimum frequency • Know that 3 days/week produces health benefits • Concern about injury risk with 150 minutes from only 1 or 2 days/week • In the observational studies reporting health benefits of medium (& high) amounts of activity, it appears most people spread the activity throughout the week.

30. Comments on 75 Minute Guideline (1) • One minute of vigorous-intensity activity counts the same as two minutes of moderate-intensity activity. Why? • Explained in detail in appendix in guidelines • In brief, adult guidelines based upon total amount of physical activity measured in MET-minutes • 500 to 1000 met-minutes/week = range of substantial health benefits • 1 MET = rate of energy expenditure at rest • Moderate-intensity = 3.0 to 5.9 METs (e.g. walking at 3.0 mph = 3.2 METs) • Vigorous-intensity = 6.0 and higher METs (e.g. running at 10 minutes/mile = 10 METs) • 150 minutes x 3.0 METs = 75 minutes x 6.0 METs

31. Additional & More ExtensiveHealth Benefits Guideline • “For additional and more extensive health benefits, adults should increase their aerobic physical activity to: • 300 minutes (5 hours) a week of moderate-intensity, • OR • 150 minutes a week of vigorous-intensity aerobic physical activity • OR • an equivalent combination of moderate- and vigorous-intensity activity.” • “Additional health benefits are gained by engaging in physical activity beyond this amount.”

32. Comments onAdditional Health Benefits Guideline • Some health benefits of PA occur with as little as 150 minutes/week of moderate-intensity PA e.g. • Lower risk of coronary heart disease • As total activity increases from 150 to 300 minutes of moderate-intensity PA/week, two things happen: • Additional benefits accrue, e.g. lower risk of breast cancer • More extensive benefits accrue, e.g., risk of heart disease is significantly lower with 300 minutes/week compared to 150 minutes/week • As total activity increases upward from 300 minutes/week, • Greater benefits accrue in a dose-response fashion, but decreasing marginal benefit for each additional minute • No known upper limit where benefits no longer increase • Risk of injury increases as volume increases

33. Muscle-Strengthening Guideline • “Adults should also do muscle-strengthening activities that are moderate or high intensity and involve all major muscle groups on 2 or more days a week, as these activities provide additional health benefits.”

34. Comments onMuscle-Strengthening Guideline • Requires moderate to high level of intensity or effort: • Relatively few repetitions (e.g. 8-12) • If do resistance training, 1 set sufficient • At least 2 days a week: • Insufficient data to comment on whether these should be non-consecutive days, or whether there is upper limit to days/week • Major muscle groups: • legs, hips, back, chest, abdomen, shoulders, arms

35. What about Physical Activityand Weight Control? • Chapter of the PAGAC report on energy balance. • PA guidelines do NOT include the advice in the Dietary Guidelines re: • 60 minutes for prevention of weight gain • 90 minutes to sustain weight loss • PA guidelines regard obesity as one of many chronic condition for which “more is better” • A statement like “30 minutes is commonly not enough to obtain a healthy weight” is parallel to most other chronic conditions e.g. “30 minutes is commonly not enough to totally reduce risk of heart disease.” • PAGAC report • Cannot specify the amount of physical activity necessary to control weight without specifying conditions of dietary intake • Large variability among individuals as to the amount of physical activity required for a healthy weight.

36. Guidance on Physical Activity & Weight Management (2) • First step = meet minimum level of PA (e.g. 150 min/wk of moderate-intensity) • Then monitor body weight and, if necessary, increase amount of physical to a point that is individually effective in achieving a healthy body weight • Guidelines note some people require 300+ minutes of moderate-intensity PA/week • Important to both increase PA and control caloric intake • All activities that expend calories (both baseline and physical activity) help control body weight • Vigorous intensity activity is much more time-efficient way to achieve NET increases in caloric expenditure • “The good news for people needing to lose weight is that regular physical activity provides major health benefits, no matter how their weight changes over time.”

37. What about Flexibility Activities? • Flexibility activities are acceptable • No known health benefits • Insufficient evidence that activities like stretching reduce injury risk • Time spend in flexibility activities by themselves does not count toward meeting guidelines • Acceptable: • Flexibility activities are usually part of exercise programs • Flexibility is a component of fitness • People need sufficient flexibility to be active • Flexibility activities, like stretching, do increase flexibility

38. What About Warm-Ups and Cool Down? • Warm-up and Cool Down activities are acceptable. • Insufficient data that these activities by themselves reduce injury risk • These activities can count toward guidelines if at least moderate-intensity • E.g. walking to warm up for a run • Acceptable: • Commonly part of exercise programs • May make activity more pleasant

39. Older AdultsAges 65+

40. Key Older Adult Guidelines • The 4 key guidelines for adults apply to older adults, but there are 4 additional qualifying guidelines • Guideline for adults who cannot do 150 minutes/week • Balance exercise • Only use relative intensity to determine the level of effort • Chronic conditions and injury risk

41. Guideline for Older AdultsWho Cannot Do 150 Minutes/Week • “When older adults cannot do 150 minutes of moderate-intensity aerobic activity a week because of chronic conditions, they should be as physically active as their abilities and conditions allow.” • Comment: • For example, physical activity has a beneficial effect on functional limitations in older adults, meaning adults with limitations should be active as their abilities allow • Guidelines note that this and other guidelines for older adults apply to people below age 65 with low levels of fitness and significant chronic conditions

42. Balance Exercise Guideline • “Older adults should do exercises that maintain or improve balance if they are at risk of falling.” • Comment: • Insufficient evidence to make this a general guideline for all older adults • Research has studied mainly exercise programs, and hence guideline uses “exercise.” • Balance training in context of evidence-based fall prevention programs is preferable

43. Chronic Conditions and Injury Risk • “Older adults with chronic conditions should understand whether and how their conditions affect their ability to do regular physical activity safely.” • Comment • Appropriate for exercise programs to screen participants for symptoms & chronic conditions. • So many possible symptoms & conditions, checklists

44. Safe And ActiveInjury Prevention for All Ages

45. Key Injury Prevention Guidelines • Understand risks, but benefits clearly outweigh risks. • Can lower injury risk though choosing appropriate activity • Injury risk of walking is low; football is high • Increase physical activity gradually over time • Follow principles of injury prevention • Consult a health care provider if you have chronic conditions or symptoms

46. Increase Gradually Over Time (1) • “Increase physical activity gradually over time whenever more activity is necessary to meet guidelines or health goals. Inactive people should “start low and go slow” by gradually increasing how often and how long activities are done.” • Comment: • No standard for how to increase gradually over time • Use relative intensity to guide increases in level of aerobic activity; generally start with relatively moderate-intensity; increase frequency and duration first, later increase intensity

47. Increase Gradually over Time (2) • “The available scientific evidence suggests that adding a small and comfortable amount of light- to moderate-intensity activity, such as 5 to15 minutes of walking per session, 2 to 3 times a week, to one’s usual activities has a low risk of musculoskeletal injury and no known risk of severe cardiac events.” • Comment • Risk of severe cardiac events only documented for vigorous activity

48. Health Care Provider Consultation • “The protective value of a medical consultation for persons with or without chronic diseases who are interested in increasing their physical activity level is not established.” • Comment: • Healthy adults and older adults (with no chronic conditions, no symptoms) do NOT need to see a health care provider about physical activity (e.g. for any type of “screening”) • Not necessary to consult health care provider prior to vigorous activity, if increase gradually over time and remain asymptomatic.

49. Additional Considerations for Some Adults

50. Additional Considerations Other subgroups of the population in the Physical Activity Guidelines for Americans include: Persons with disabilities Adults with selected chronic conditions Women during pregnancy and the postpartum period