1. The Public Health Importance of Physical Inactivity National Physical Activity Task Force Edinburgh June 13, 2001 Steven N. Blair Director of Research—Cooper Institute Visiting Professor and Benjamin Meaker Fellow University of Bristol

2. A Brief Historical Note Systematic research on the relation of sedentary habits to coronary heart disease began in the 1950s with the pioneering work of Professor Jeremy Morris of London Dozens of studies now present a compelling body of evidence supporting regular physical activity as a good health habit Today I will attempt to persuade you that inactivity is one of the most important public health issues, and that governments must act to deal with this threat to health. Further, I predict that this will become widely recognized

3. Outline of Lecture Strength of inactivity/low fitness as predictors of mortality Prevalence of inactivity Population attributable risk Hostile environment Lifestyle physical activity interventions Summary and conclusion

4. Death Rates and RR for Selected Mortality Predictors, Men, ACLS Death rates and relative risks are adjusted for age and examination year Relative risks are for risk categories shown here compared with those not at risk on that predictor Blair SN et al. JAMA 1996; 276:205-10

5. Death Rates and RR for Selected Mortality Predictors, Women, ACLS Death rates and relative risks are adjusted for age and examination year Relative risks are for risk categories shown here compared with those not at risk on that predictor Blair SN et al. JAMA 1996; 276:205-10

6. Cardiorespiratory Fitness, Risk Factors and All-Cause Mortality, Men, ACLS # of risk factors Risk Factors current smoking SBP >140 mmHg Chol >240 mg/dl Cardiorespiratory Fitness Groups *Adjusted for age, exam year, and other risk factors Blair SN et al. JAMA 1996; 276:205-10

7. Cardiorespiratory Fitness, Risk Factors, and All-Cause Mortality, Women, ACLS # of risk factors Risk factors current smoking SBP >140 mmHg Chol >240 mg/dl Cardiorespiratory Fitness Groups *Adjusted for age, exam year, and other risk factors Blair SN et al. JAMA 1996; 276:205-10

8. Functional Health Status

9. Fitness and Functional Limitations Prospective study of 1,175 women and 3,495 men age 40 years and older Medical exam during 1980-88 Average follow-up of 5.5 years Self-report of functional limitations in 1990 by mail-back survey –Are you physically able to do? personal care activities household activities recreational activities Huang et al. MSSE 1998, 30:1430-5

10. Prevalence of Self-reported Functional Limitations by Fitness and Age Groups *Prevalence (%) Huang et al. MSSE 1998, 30:1430-5

11. Fitness and Functional Limitations, Women and Men, ACLS OR for self-reported functional limitation adjusted for age, follow-up, BMI, smoking, alcohol intake, baseline disease, & disease at follow-up Huang et al. MSSE 1998, 30:1430-5

12. Cardiorespiratory Fitness and Longevity

13. Population Attributable Risk of Low CRF and Economic Issues

14. Physical Activity Levels for U.S. Adults 25% 38% 22% 15% n Sedentary and Irregularly Activity n Regularly Active, Low to Moderate Intensity n Regular Vigorous Activity (3 days, 20 minutes) Surgeon General’s Report, 1996

15. Population Attributable Risk (PAR) for All-Cause Mortality in 10,623 Normal Weight Men, ACLS RR adjusted for age, examination year, parental CVD, and all other items in the table Wei et al. JAMA 1999; 282:1547

16. Population Attributable Risk (PAR) for All-Cause Mortality in 11,798 Overweight Men, ACLS RR adjusted for age, examination year, parental CVD, and all other items in the table Wei et al. JAMA 1999; 282:1547

17. Population Attributable Risk (PAR) for All-Cause Mortality in 3293 Obese Men, ACLS RR adjusted for age, examination year, parental CVD, and all other items in the table Wei et al. JAMA 1999; 282:1547

18. Physical Inactivity and Direct Medical Costs Cross-sectional stratified analysis of 1987 National Medical Expenditures Survey Non-institutionalized women and men 15 years and older 35,000 persons in 14,000 households Detailed information on health care costs were collected and confirmed by an additional survey of medical providers 20,041 non-pregnant participants included in the analyses Pratt M et al. Physician & Sportsmedicine 2000

19. Physical Inactivity and Direct Medical Costs Physical activity categories –Physically active=30 minutes of moderate or strenuous activity 3 or more days/week –Physically inactive=all others Medical care costs included –Hospital admissions –Physician visits –Medication use Pratt M et al. Physician & Sportsmedicine 2000

20. Physical Inactivity and Direct Medical Costs Total medical care costs –All respondents=$1,690 Physically active=$1,242 Physically inactive=$2,277 Differences in costs between active and inactive individuals were present by categories of smoking habit, gender, and age groups Total cost of inactivity for medical care for the U.S. in 2000 is estimated at $76.6 billion Pratt M et al. Physician & Sportsmedicine 2000

21. Summary: Physical Inactivity and Health A sedentary and unfit way of life is harmful to health and function A high proportion of adults in most countries are sedentary Population attributable risks and health care costs of physical inactivity are substantial There is a crucial need to develop policies to address this major public health problem

22. Decline in Energy Expenditure in the United Kingdom, 1970-1995 Estimate of energy intake from surveys of household food intakes and making assumptions about food and drink outside the home –Decline of 750 kcal per day Average weight gain of 2.5 kg in the population over the same period –Accounts for an additional 50 kcal per day Therefore, the average decline in the UK is about 800 kcal per day in the past 25 years James PT. Int J Obes 1995

23. Lifestyle and Energy Expenditure Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

24. Lifestyle and Energy Expenditure Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

25. Lifestyle and Energy Expenditure Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

26. Lifestyle and Energy Expenditure Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

27. Lifestyle and Energy Expenditure Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

28. Lifestyle and Energy Expenditure Assume a person’s caloric intake remains the same Completing all of the tasks reviewed daily or as listed –Active way=10,500 kcal/month –Sedentary way=1,700 kcal/month Difference of 8,800 kcal/month is energy equivalent of 2.5 pounds/month or 30 pounds/year Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999

29. Lifestyle Physical Activity Interventions

30. Experimental Design  Two year, parallel randomized design  Two treatment groups: Lifestyle Structured  Six months of active intervention; 18 months of follow-up intervention  Three successive recruitment cohorts Dunn A et al. JAMA 1999

31. Structured Intervention: Project Active  Exercise prescription model, e.g., 50-85% of maximal aerobic power for 20-60 minutes per session, at least 3 and preferably 5 days per week  State-of-the-art fitness center for first 6 months  Follow-up includes quarterly newsletter and group activities, e.g., fun runs Dunn A et al. JAMA 1999

32. Lifestyle Intervention: Project Active  Goal is to increase energy expenditure using behavioral interventions and processes matched to stage of motivational readiness  Small group meetings once per week for four months, then every two weeks for two months  Follow-up includes monthly meetings through the end of year 1 then graduated down through year 2 Dunn A et al. JAMA 1999

33. Behavioral Approaches to Physical Activity Interventions Theoretical foundations –Social Learning Theory –Stages of Change Model –Environmental/Ecological Model Methods –Problem solving –Self-monitoring –Goal setting –Social support –Cognitive restructuring –Incremental changes –Manipulating the environment Dunn A et al. JAMA 1999

34. Curriculum Overview Dunn A et al. JAMA 1999

35. How Do People Change? Cognitive Strategies Increasing KnowledgeEncourage person to read and think about physical activity Warning of RisksProvide person with message that being inactive is very unhealthy Caring about Consequences Encourage person to recognize to Others how his/her inactivity affects his/her family and friends Comprehending BenefitsHelp person to think about the personal benefits of being active Increasing Healthy Help person to become aware of Opportunitiessocietal changes in regard to physical activity Dunn A et al. JAMA 1999

36. How Do People Change? Behavioral Strategies Substituting AlternativesEncourage person to engage in physical activity when it might be most beneficial, yet is rarely done Enlisting Social SupportEncourage person to find a friend or family member who will provide support for being active Rewarding YourselfEncourage person to reward and praise self for being active Committing YourselfEncourage person to make commitment to be active Reminding YourselfHelp person to set up reminders to be active Dunn A et al. JAMA 1999

37. Mean Peak Oxygen Consumption ml. kg -1. min -1 time in months Dunn A et al. JAMA 1999

38. 24-Month Change in Weight and Percent Body Fat Weight Percent Body Fat * p < 0.001 within group * * kilograms - 3 -1.5 0 1.5 Lifestyle Structured 1.5 percent 0 -1.5 - 3 Dunn A et al. JAMA 1999

39. 24-Month Reduction in Blood Pressure mm Hg Systolic Diastolic * p < 0.01 within group * * * * Dunn A et al. JAMA 1999

40. Enlisting social support Seeking out others to provide support for and encourage participation in physical activity äI have a healthy friend that encourages me to be physically active when I don’t feel up to it äI have someone on whom I can depend when I am having problems with being physically active

41. Rewarding yourself Using rewards to encourage or maintain physical activity behavior äI reward myself when I am physically active äI do something nice for myself for making efforts to be more physically active

42. Reminding yourself Positive reminders to engage in physical activity äI put things around my home to remind me of exercising äI keep things around my place of work that remind me to be physically active

43. Substituting alternatives Replacing sedentary pursuits with more active behaviors äInstead of remaining inactive, I engage in some physical activity äWhen I’m feeling tense, I find that being physically active helps relieve my worries

44. Committing yourself Making commitments toward being more physically active äI make commitments to be physically active äI am the only one responsible for my health, and only I can decide whether or not I will be physically active

45. Measures Independent Measures –Processes of Change - 40-item questionnaire Marcus, Rossi, Selby, Niaura, & Abrams, 1992 5 Cognitive Processes 5 Behavioral Processes

46. Implications Effective measurement of these key mediating constructs exist Interventions have been shown to be effective in modifying these variables Change in the mediating variables is associated with changes in behavior Researchers and practitioners should address behavioral and cognitive strategies in the promotion of short- and long-term physical activity

47. Public Health Recommendations for Physical Activity

48. Public Health Recommendation for Physical Activity Recent statements from the American College of Sports Medicine/Centers for Disease Control and Prevention, American Heart Association, NIH, and the office of the US Surgeon General conclude: –All adults should accumulate at least 30 minutes of at least moderate intensity physical activity each day –This is equivalent to walking about 2 miles at a pace of 3 to 4 mph

49. Summary Physical inactivity and low levels of cardiorespiratory fitness are strong predictors of mortality and other health problems There is a high prevalence of sedentary habits—40-50 million adults in the U.S. Population attributable risks and economic costs of inactivity are high

50. Best Exercise Advice to Give to the Public? Traditional, structured program--3-5 times/week, 20-60 minutes/session, relatively vigorous Consensus recommendation--accumulate at least 30 minutes of moderate intensity exercise each day The important question is not whether one approach is better than the other, but do both approaches work?

51. What Is the Best Exercise? The one you will do regularly No matter how excellent the exercise is or how effective the program might be, it will not produce any benefits for you if you do not do it

52. Conclusion Physical inactivity is one of the most important public health problems and it is important to develop an action plan to address this issue –Policy makers –Public health professionals –Health service providers –Educators –Grassroots activists