Physical Inactivity: A Major Public Health Problem XIV International Congress on Physical Education, Sports, and Clinical Applications Monterrey, MEXICO October 18, 2006 Steven N. Blair Department of Exercise Science University of South Carolina Department of Kinesiology, Health Promotion and Recreation University of North Texas
Outline of Lecture Current data on sedentary living, low fitness, and health status Prevalence of inactivity What to do to address the public health problem of physical inactivity
Aerobics Center Longitudinal Study
Design of the ACLS 1970 More than 80,000 patients 2005 Cooper Clinic examinations--including history and physical exam, clinical tests, body composition, EBT, and CRF Mortality surveillance to 2003 More than 4000 deaths 1982 86 90 95 99 04 Mail-back surveys for case finding and monitoring habits and other characteristics
Aerobics Center Longitudinal Study Prospective investigation of 7,080 women and 25,341 men examined at the Cooper Clinic at least once during 1970-1989 Average age: women=42.7 yrs; men=42.9 yrs Approximately 97% white, mid- to uppersocioeconomic strata Followed for mortality to 12/31/89 89 deaths during 52,982 woman-years 601 deaths during 211,996 man-years Blair SN et al. JAMA 1996; 276:205-10
CVD Death Rates* by Fitness Groups, 7,080 Women and 25,340 Men, ACLS Deaths/10,000 PY 20 15 10 Low Mod High 5 0 Women Men Adjusted for age, exam year, and other risk factors Blair SN et al. JAMA 1996; 276:205-10
Amount of Specific Physical Activities for Moderately Fit Women and Men Detailed physical activity assessments in women and men who also completed a maximal exercise test Average min/week for the moderately fit who only reported each specific activity Mean Min/week 160 140 120 100 80 60 40 20 0 Women Men Walk Aerobics Run Stofan JR et al. AJPH 1998; 88:1807 N=3,972 13,444
Older Women and Men
Risk of Death by Fitness Groups, 749 Women and 1758 Men 60 and Older, ACLS Age, exam-year, BMI, cholesterol, high blood pressure, diabetes, smoking, CVD, parental CVD adjusted RR for all-cause mortality Patients with cancer and failure to achieve at least 85% of predicted max HR were excluded RR 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Women Blair & Wei. Am J Health Prom. 2000 Men Low Moderate High
Death Rates/1000 by Fitness Groups, 2135 Men Aged 60 and Older, ACLS Crude death rate/1000 PY 120 100 80 60 40 20 0 Low Moderate High 60-69 70-79 80+ Age Groups (years) Blair & Wei. Am J Health Prom 2000; 15:1-8
Fitness and Functional Limitations, Women and Men, ACLS Risk of self-reported functional limitation adjusted for age, follow-up, BMI, smoking, alcohol intake, baseline disease, & disease at follow-up 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Women Men Low Moderate High Huang et al. MSSE 1998, 30:1430-5
Physical Activity and Dementia in Women and Men, 65 Years Age- and sex-adjusted Hazard ratio for incident dementia 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 <3/week Exercise Habits 3+/week Exercise and incident dementia In 1740 women and men Larsen EB et al. Ann Int Med 2006; 144:73-81 Age-specific incidence of dementia/1000 person-years 60 50 40 30 20 10 0 <=10 SPPB 11+ SPPB Short physical performance battery scores and dementia in 2288 women and men Wang L et al. Arch Int Med 2006; 166:1115
Cardiorespiratory Fitness and Hypertension
CRF and Risk of Incident Hypertension, ACLS Women 4,884 healthy women examined at the Cooper Clinic, 1970-1998 157 women developed hypertension during average follow-up of 5 years Risk adjusted for age, exam year, alcohol intake, smoking, BP, family history of hypertension, waist girth, glucose, & triglycerides Risk of Developing Hypertension 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 P for trend <0.01 Low Moderate High Fitness Groups Barlow CE et al. Am J Epidemiol 2006; 163:142-50
Metabolic Syndrome and Type 2 Diabetes
The Metabolic Syndrome Metabolic syndrome is now listed as a disease in the International Classification of Diseases Metabolic syndrome is defined* as any 3 of: High blood sugar High triglycerides Low HDL-cholesterol High blood pressure High waist circumference *ATP III criteria-u.s.a.
Cardiorespiratory Fitness and Metabolic Syndrome ACLS, 1979-2003 9007 men (44 yr, 25 kg/m 2 ) 1491 women (44 yr, 22 kg/m 2 ) Free of CVD, Cancer, Metsyn Follow-up: mean 5.7 yrs, 52,000 man-yrs, 8275 woman-yrs Cases: 1346 men, 56 women Age-adjusted Rate/1,000 45 40 35 30 25 20 15 10 5 0 Men Fitness: Low Middle High P<0.001, each Women LaMonte M et al. Circulation. 2005; 112:505-512
Multivariable Hazards Ratio* Risk of Developing Metabolic Syndrome by Fitness Level and BMI, ACLS Men 1.4 1.2 1 0.8 0.6 0.4 0.2 0 ACLS, 1979-2003 P<0.001, each Fitness: Low Middle High <25 >=25 BMI, kg/m 2 BMI, kg/m 2 *Adjusted for age, smoking, alcohol, family history, exam year, and number of baseline metabolic syndrome components. LaMonte M et al. Circulation. 2005; 112:505-512
All-Cause Mortality by Fitness Groups in 3,757 Men with Metabolic Syndrome Odds Ratio 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 Low Moderate High Cardiorespiratory Fitness Groups Katzmarzyk et al. Arch Int Med 2004; 164:1092 p for trend <0.001
Muscle Strength and Health Outcomes
Muscular Strength and Incidence of Metabolic Syndrome, ACLS Men 3,233 men 20-85 years at baseline Free of cancer, CHD, and stroke Muscular strength 1-RM bench press and leg press Expressed as kg lifted per kg body weight Two examinations Mean interval=7.3 years Jurca R et al. MSSE 2005; 37:1849-55
Adjusted Risk of Incident Metabolic Syndrome by Muscular Strength Groups, ACLS Men Adjusted Risk* 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 *Adj for age, exam yr, follow-up time, #met syndrome factors, smoking, & alcohol intake p for trend=0.002 Q1 Q2 Q3 Q4 *Adj for age, exam yr, follow-up time, #met syndrome factors, smoking, alcohol intake, & CRF p for trend=0.05 Results are similar in BMI groups (<25 & 25; and for all age groups) Jurca R et al. MSSE 2005; 37:1849-55 Fourths of muscular strength
Age-Adjusted Incidence of Hypertension (372 Cases) in 2042 Prehypertensive Men, ACLS Age-adjusted rate/1,000 man-years 25 20 15 10 5 0 Linear Trend p<0.01 Fourths of Muscular Strength Jurca R et al. In progress
Mortality Rates per 10,000 Person- Years by Musculoskeletal Fitness Category, ACLS Mortality rate per 10,000 PY 40 35 30 25 20 15 10 5 0 Low MSF Moderate MSF High MSF N=1069 N=7008 N=1028 FitzGerald S et al. J Phys Act Health 2004; 1:7-18
Muscular Strength and Mortality in Men With Metabolic Syndrome Age-Adj Deaths/10,000 MY 60 50 P <0.02 40 30 20 10 0 Low Strength High Strength Jurca R. ACSM abstract. 2005
Benefits of Physical Activity for Individuals of Any Size
RR for All-cause and CVD Mortality in Fit and Unfit ACLS Men by Body Fat Categories Adj RR* 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 Fit Unfit <17 17-25 >25 <17 17-25 >25 Body Fat% All-cause Mortality Body Fat% CVD Mortality *adjusted for age, exam year, smoking, alcohol, & parental history Lee CD, Blair SN, & Jackson AS. Am J Clin Nurt 1999; 69:373-80
Adjusted RR for All-Cause Mortality by Fitness and BMI, ACLS Women Adj RR* *adj for age, exam year, smoking, & health status 4 3.5 3 2.5 2 1.5 1 0.5 0 Fit Unfit Normal Weight Overweight Obese Farrell et al. Obes Res. 2002; 10:417-423
CVD Mortality Risk* by Fitness and BMI Categories, 2316 Men with Diabetes, 179 CVD Deaths 10 9 Risk of CVD Mortality 8 7 6 5 4 3 2 1 p for trend <0.0001 Reference p for trend <0.0001 p for trend <0.002 0 Low Moderate High Low Moderate High Low Mod/High 18.5 < BMI <25.0 25.0 BMI <30.0 30.0 BMI < 35.0 *Adj for age and examination year Church TS et al. Arch Int Med 2005; 165:2114
Physical Activity as a Clinical Intervention Long history of using physical activity as a treatment of CHD What about using activity to treat other diseases and conditions?
Change in Activity and Reinfarction, 406 Mexican- American and Non-Hispanic White Women and Men, Corpus Christi Project Physical activity assessed at baseline and at 5 annual follow-up examinations Multivariable adjusted risk for reinfarction 0.9 1 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Increased activity Active, no change Decreased activity Sed, no change Steffen-Batey L et al. Circulation 2000; 102:2204
CVD Mortality Risk* by Maximal METs, 2316 Men with Diabetes, 179 CVD Deaths Risk of CVD Mortality 4 3 2 1 0 p for trend <0.001 Reference category <7 7.0-7.9 8.0-8.9 9.0-9.9 10.0-10.9 11.0-11.9 12.0-12.9 13.0 Maximal METs *Adj for age and examination year Church TS et al. Arch Int Med 2005; 165:2114
Physical Activity and Survival 2987 Women with Breast Cancer Nurses Health Study Multivariable adjusted relative risk 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 <3 3-8.9 9-14.9 15-23.9 24+ Physical Activity in MET-hours/Week Similar findings for breast cancer recurrance Holmes MD et al. JAMA 2005; 293:2479
Yes, But Those Are Observational Studies, and We Require Randomized Clinical Trial Evidence
Exercise Is As Good As Other Treatments for Clinical Depression % of Patients with Remission of Depression 50 40 30 20 10 0 Control 80 Min/Week 180 Min/Week Amount of Brisk Walking Drug therapy and cognitive behavioral therapy produce remission in approximately 40% of clinically depressed individuals Dunn A et al. Am J Prev Med 2005
Exercise Training and Angioplasty, 101 Men with Stable CAD Event-free survival (%) 90 80 70 60 50 40 30 Per unit change in angina-ccs $7,000 $6,000 $5,000 $4,000 $3,000 $2,000 20 $1,000 10 0 Exercise Angioplasty $0 Exercise Angioplasty Exercise was 20 minutes/day on a cycle ergometer Hambrecht R et al. Circulation 2004; 109:1371
Public Health Burden of Inactivity and Low Fitness
Attributable Fractions (%) for All-Cause Deaths 40,842 Men & 12,943 Women, ACLS 18 16 14 12 10 8 6 4 2 0 Men Women Low CRF High Chol Hypertension Obese Smoker Diabetes Aerobics Center Longitudinal Study, 1970-2004. In progress
What Do We Do About the Toxic Environment that Produces Obesity and Inactivity?
The problem No, not me or the recliner The remote
Lifestyle and Energy Expenditure Sedentary Way kcal Using remote to change channel 30 min of phone calls--reclining Using garage door opener Hiring maid to clean and iron Active Way <1 Getting up and changing channel 4 Standing for 3 X 10 minute calls <1 Opening garage door twice/day 0 30 min of ironing 30 min vacuuming kcal 3 20 2-3 152 Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999
Lifestyle and Energy Expenditure Sedentary Way kcal 30 min waiting for pizza delivery Buying pre-sliced vegetables Using a leaf blower for 30 min Using a lawn service Active Way kcal 15 30 min of cooking 25 0 15 min washing, slicing & chopping 100 30 min of raking leaves 0 30 min/week each gardening, mowing 10-13 150 360 Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999
Lifestyle and Energy Expenditure Sedentary Way kcal Using car wash once/month Letting dog out the back door Drive 40 min, 5 min walk (parking) Emailing colleague, 4 min Active Way 18 Washing & waxing car, 1 hr/month 2 Walking dog for 30 min 22 15 min walk to bus stop, 2 X day 2-3 Walk 1 min, talk 3 min (standing) Kcal 300 125 Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999 60 6
Lifestyle and Energy Expenditure Sedentary Way kcal Taking elevator up 3 flights Park close as poss, 10 sec walk Cashier unloads shopping cart Ride escalator 3 times Active Way 0.3 Walking up 3 flights of stairs 0.3 Park 1 st spot, 2 min walk, 5 X week 2 Unload full shopping cart 2 1 flight of stairs, 3 X week in mall kcal Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999 15 8 6 15
Lifestyle and Energy Expenditure Sedentary Way kcal Active Way kcal 1 hour internet shopping 30 Shopping mall, walking 1 hour 145-240 Sitting in car at 15 Parking & walking 70 drive-in window, 30 min inside, 3 X week, total of 30 min Paying at the 0.6 Walking in to pay, 5 pump 1 X week Sitting & listening 30 Giving lecture 70 to lecture, 60 min Kcal estimates for 150-160 pound person Taken from article by L. Beil, Dallas Morning News, 1999
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
Consensus Public Health Recommendation for Physical Activity Statements from the American College of Sports Medicine/Centers for Disease Control and Prevention, American Heart Association, NIH, the US Surgeon General, and U.S. Dietary Guidelines 2005 conclude: All adults should accumulate at least 30 minutes of at least moderate intensity physical activity each day This is equivalent to walking about 1.5 miles at a pace of 3 to 4 mph Doing more exercise and perhaps more strenuous exercise may produce additional health benefits Resistance exercise provides health benefits
Fitness Prescription 3-5 days per week 20-60 minutes, in one bout 60-90% max. heart rate (i.e., vigorous) Which is Right? Public Health Guide 5+ days per week Accumulate at least 30 minutes At least moderateintensity (e.g., brisk walk)
Percent Change Fitness 10 8 6 4 2 0-2 Change in VO 2 max DREW -1.1 Study (n=381) All highly significant versus control P trend < 0.0001 3.7 Control 75 minutes 150 minutes 225 minutes 6.9 Study Groups 9.3 Adj. baseline fitness, age, ethnicity and RER
We desperately need a call to action to address the problem of sedentary living patterns that are prevalent in North Americans of all ages, both genders, all SES strata, and in all racial and ethnic groups
Trends in Riding Lawnmower Sales in the US: 1981-2001 In thousands 1600 1400 1200 1000 800 600 400 200 0 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Final Advice Remember to walk the dog every day But not like this! Even if you do not have one
Thank You
Muscular Strength and Prevalence of Metabolic Syndrome, ACLS Men 8570 men 20-75 years at baseline Muscular strength 1-RM bench press and leg press Scores for the two tests were summed and expressed as kg lifted per kg body weight Men assigned to fourths of strength index within age groups (20-29, 30-39, 40-49, 50-59, and 60+ years) Jurca R et al. MSSE 2004; 36:1301-7
Age and Smoking Adjusted Prevalence of Metabolic Syndrome by Fitness Groups in 8570 ACLS Men % 50 40 30 20 10 0 Q1 Q2 Q3 Q4 Low Moderate High Cardiorespiratory Fitness Groups (p <0.0001) Muscular Strength (p <0.0001 for low CRF p <0.0002 for moderate CRF) Jurca R et al. MSSE 2004; 36:1301-7
What is the most frequent reason for not being more physically active? Lack of Time
30 minutes
How Many Obese Individuals Are Fit?
Prevalence of Moderate or High Fitness, ACLS Women Farrell SW et al. Obes Res 2002; 10:417
Overweight and Obese Persons Can Be Active and Fit
What Must We Do to Substantially Reduce the Number of Sedentary Adults? Continue the development of methods to increase the individual adoption and maintenance of regular physical activity Greatly increase creative approaches and research into the effects of legislation, public policy, social norm, and environmental changes on physical activity Develop media messages promoting physical activity that are as effective as the media messages aimed at getting us to buy products we do not need or want