Health Benefits from Regular Exercise

DECLINE IN DEATHS

Harvard Alumni Study (1985) Amount of physical activity Mortality

Exercise and Chronic Diseases Regular exercise reduces risk of or benefits: atherosclerosis and coronary heart disease – TC,  LDL-C,  HDL-C,  TG, heart strength

DEVELOPMENT OF ATHEROSCLEROSIS

The first step of atherosclerosis is Inflammation Injury Cancer Diabetes More cancer

ARTERY COMPARISONS

Coronary Artery Disease Atherosclerosis—progressive narrowing of arteries due to build up of plaque Coronary artery disease (CAD)— atherosclerosis in the coronary arteries Ischemia—deficiency in blood to heart caused by CAD Myocardial infarction—heart attack due to ischemia

AMERICANS AT INCREASED CAD RISK

Did You Know…? Atherosclerosis begins in infancy and progresses at different rates, depending primarily on heredity and lifestyle choices such as smoking history, diet practices, physical activity, and stress.

Exercise and Chronic Diseases Regular exercise reduces risk of or benefits: atherosclerosis and coronary heart disease – TC,  LDL-C,  HDL-C,  TG, heart strength hypertension – BP

Hypertension chronically elevated blood pressure causes the heart to work harder places strain on arteries causing them to become less elastic over time affects ~25% of adult Americans –half of these are unaware they have hypertension

Classification of Blood Pressure for Adults, Age 18 Years and Older Normal< 130< 85 High normal Hypertension  140  90 Stage 1 (mild) Stage 2 (moderate) Stage 3 (severe) Stage 4 (very severe)  210  120 SystolicDiastolic Category(mmHg)(mmHg)

Exercise and Chronic Diseases Regular exercise reduces risk of or benefits: atherosclerosis and coronary heart disease – TC,  LDL-C,  HDL-C,  TG, heart strength hypertension – BP in hypertensive (but doesn’t normalize)  colon and breast cancer

Exercise and Chronic Diseases Regular exercise reduces risk of or benefits: atherosclerosis and coronary heart disease – TC,  LDL-C,  HDL-C,  TG hypertension – BP in hypertensive (but doesn’t normalize)  colon and breast cancer diabetes mellitus –exercise  need for insulin

Exercise and Chronic Diseases obesity – energy expenditure

Obesity and Overweight in the US  prevalence dramatically  past 30 y  prevalence in children  markedly since 1980  >33% of adult population is overweight  average adult gains 1 lb/yr after age 25 y  average adult loses 0.5 lb of muscle and bone mass each year after age 25 y

Obesity Trends* Among U.S. Adults BRFSS, 1985 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1986 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1987 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1988 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1989 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1990 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1991 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1992 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1993 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1994 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1995 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1996 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1997 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1998 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 1999 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 2000 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 2001 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” woman) Source: Behavioral Risk Factor Surveillance System, CDC No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person) Obesity Trends* Among U.S. Adults BRFSS, 2002 No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 2003 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 2004 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity Trends* Among U.S. Adults BRFSS, 2005 (*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

Prevalence of Overweight Among U.S. Children and Adolescents (Aged 2 –19 Years) National Health and Nutrition Examination Surveys (NHANES) % 15% 10% 5% 0% Non-Hispanic whites Non-Hispanic blacks Mexican Americans

Fat Distribution Upper-body (android) obesity Fat stored in upper body and abdominal area (apple shaped) Occurs more frequently in men Carries greater risk for CAD, hypertension, stroke, and diabetes Lower-body (gynoid) obesity Occurs more frequently in women Fat stored in the lower body around the hips, buttocks, and thighs (pear shaped)

BODY CHANGES, DIET, AND EXERCISE

Exercise and Chronic Diseases obesity – energy expenditure low-back pain –a leading cause for missed work mental health – mental well-being osteoporosis –weight-bearing exercise  bone mineral density

Two Types of Bone Cortical (compact) 80% of skeletal mass 20% of turnover Trabecular (Cancellous) vertebral bodies femoral neck 20% of skeletal mass 80% of turnover

Trabecular Bone

Bone Remodeling

Bone Turnover and Age AGE (yr)Bone Turnover Bone Loss 20-40Bone Gain = Bone Loss > 40 Bone Gain < Bone Loss

Bone Mineral Density osteoporosis

Mechanical loading on bone stimulates bone absorption of Ca 2+

Are you looking at a 65-year-old woman with osteoporosis?

Exercise Interventions in Pre-pubertal Children

Comparison of Impact Exercise vs. Weight Training on Changes in BMD of Postmenopausal Women Kohrt et al., J Bone Miner Res 12:1253, 1997 Ca 2+ supplemented at 1500 mg/d 3 d/wk; 45 min sessions for 11 mo jogging / stair climbing vs. weight training

Summary Maintaining good bone health is a lifelong process Exercise (and proper nutrition) are vital in enhancing peak BMD in childhood and in maintaining or increasing BMD in adults

Exercise Prescription Components of Fitness cardiovascular body composition muscular strength and endurance flexibility

Exercise Prescription Cardiovascular Fitness 1995 CDC/ACSM health recommendation: –“at least 30 minutes of moderate intensity exercise on most or preferably all days of the week” expend at least 1000 kcal/week (= to 30 min of brisk walking 5-6 days/week) minimal fitness recommendations: –expend kcal/week equal to min/week of moderate-intensity running (9-min/mile pace)

Exercise Prescription Cardiovascular Fitness exercise mode exercise intensity –50-70% of HR max –45-60% of VO 2max –RPE of –“talk” test exercise duration exercise frequency rate of progression

Classification of Exercise Intensity Based on minutes of continuous exercise

Exercise Prescription Flexibility connective tissue primary cause of inflexibility primary concern is flexibility of lower back and hamstrings

Exercise Prescription Muscular Strength and Endurance general recommendations –one set of 8-12 repetitions –set resistance to reach volitional fatigue –at least 2 days/week –performed at moderate-to-slow speeds –full range of motion –do not alter normal breathing

Quiz 6 1.d 2.d 3.CV system less important to these events 4.c 5.High [CHO] slows fluid absorption 6.d 7.a 8.b 9. HLa production 10.c 11.c 12.d 13.c 14.b 15.c 16.a 17.6 g  9 kcal/g = 54% 18.d 19.c 20. a) BP; b) BMD; c) HDL, LDL, TC; d)  insulin needs 21. jog 3-4 X/wk at HR of ; RPE of 12-13