1. Exercise as Medicine Instructor of Medicine Department of Medicine Division of Sports Medicine Northwestern University Feinberg School of Medicine

2. Exercise as Medicine The Scope of the Problem Health Benefits of Physical Activity and Exercise Benefits of Weight Training and Muscular Fitness How to Improve Muscular Fitness Benefits of Flexibility Exercise Maintaining Effects of Exercise Prescribing Exercise Risks of Exercise

3. Risk Factors for Heart Disease Family History Cigarette Smoking Hypertension Diabetes/Impaired Fasting Glucose Obesity Sedentary Lifestyle

4. Prevalence of Sedentary Time

5. 2000 Obesity Trends* Among U.S. Adults BRFSS, 1990, 2000, 2010 (*BMI 30, or about 30 lbs. overweight for 5’4” person) 2010 1990 No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

6. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1985

7. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1986

8. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1987

9. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1988

10. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1989

11. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% Obesity Trends* Among U.S. Adults BRFSS, 1990

12. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1991

13. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1992

14. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1993

15. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1994

16. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1995

17. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% Obesity Trends* Among U.S. Adults BRFSS, 1996

18. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% ≥20% Obesity Trends* Among U.S. Adults BRFSS, 1997

19. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% ≥20% Obesity Trends* Among U.S. Adults BRFSS, 1998

20. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% ≥20% Obesity Trends* Among U.S. Adults BRFSS, 1999

21. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% ≥20% Obesity Trends* Among U.S. Adults BRFSS, 2000

22. (*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, 2001

23. (*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, 2002

24. (*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, 2003

25. (*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

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

27. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30% Obesity Trends* Among U.S. Adults BRFSS, 2006

28. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30% Obesity Trends* Among U.S. Adults BRFSS, 2007

29. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30% Obesity Trends* Among U.S. Adults BRFSS, 2008

30. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30% Obesity Trends* Among U.S. Adults BRFSS, 2009

31. (*BMI ≥30, or ~ 30 lbs. overweight for 5’ 4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30% Obesity Trends* Among U.S. Adults BRFSS, 2010

32. Exercise Recommendations ACSM/AHA Guidelines:  At least 150 minutes per week of moderate exercise or 75 minutes per week of vigorous exercise  30 minutes per day, 5 times per week  Perform activities that maintain or increase muscular strength and endurance a minimum of 2 days each week Garber et al. ACSM Postion Stand on Exercise. 2011.

33. Physical Benefits of Exercise Decreased risk of CHD, stroke, type 2 Diabetes Mellitus, colon and breast cancers Lowers blood pressure, improves cholesterol profile, CRP, increases insulin sensitivity Preserves bone mass and reduces risk of falling All-cause mortality is delayed by regularly engaging in physical activity Garber et al. ACSM Postion Stand on Exercise. 2011.

34. Psychological Benefits of Exercise Prevents/improves mild to moderate depressive disorders and anxiety Lowers risk of cognitive decline and dementia

35. Exercise Intensity Important determinant of physiological responses to exercise training DiPietro et al (2006): significant improvement in glucose utilization in sedentary older men and women who engaged in vigorous (80% VO2max) exercise  Not in those who performed moderate (65% VO2max) exercise DiPietro et al. J Appl Physiol. 2006.

36. Intensity Threshold Threshold of exercise intensity varies depending on fitness level  Higher intensity threshold for trained individuals vs. untrained individuals to improve VO2 max Little evidence for intensity threshold for changes in HDL, LDL or TG, BP, glucose intolerance or insulin resistance Butcher LR et al. Med Sci Sports Exerc. 2002.

37. Intensity Threshold Several studies suggest exercise intensity does not influence magnitude of loss of body weight or fat stores Subjects who walked at self-selected pace with fixed volume (10,000 steps/day x 3 days/wk)  Improved cholesterol profiles and expression of genes involved in reverse lipid transport  No accompanying changes in body weight and total body fat Butcher LR et al. Med Sci Sports Exerc. 2002. Butcher et al. Med Sci Sports Exerc. 2008.

38. Patterns of Exercise Discontinuous Exercise Weekend Warrior Interval Training Sedentary Behavior

39. Discontinuous Exercise Moderate-intensity physical activity may be accumulated in bouts of 10 or more min each to attain goal of at least 30 min daily Effectiveness of long vs. short bouts of exercise for improving body composition, cholesterol or mental health inconclusive  Volume of energy expended rather than the duration of exercise that is important

40. Weekend Warrior This pattern of exercise was associated with lower rates of premature mortality compared with being sedentary in a study of men without CV risk

41. Interval Training Short term (< 3 mos) has resulted in similar or greater improvements in cardiorespiratory fitness and cardiometabolic biomarkers compared to single-intensity exercise  Lipoproteins, glucose, IL-6, and TNF alpha, muscle fatty acid transport

42. Interval Training Study of healthy untrained men:  Interval running exercise more effective than sustained running of similar total duration in improving cardiorespiratory fitness and blood glucose concentrations  Less effective in improving resting HR, body composition and total cholesterol/HDL ratio

43. Sedentary Behavior Associated with elevated risk of CHD mortality, depression, increased waist circumference, elevated BP, depressed lipoprotein lipase activity and worsened chronic disease biomarkers  Glucose, insulin, lipoproteins Detrimental even among individuals who meet current physical activity recommendations

44. Sedentary Behavior Amount of time spent in activities such as TV watching and sitting at a desk should be assessed When sedentariness is broken up by short bouts of physical activity or standing, attenuation of adverse biological effects

45. Effect of Exercise on Cardiometabolic Risk Factors Improvement in high blood pressure, glucose tolerance, insulin resistance, dyslipidemia and inflammatory markers Benefits of exercise on cardiometabolic risk factors are acute (hours to days) and chronic  Regular exercise participation on most days of the week is important

46. Exercise + Diet Modification Exercise without dietary modification has modest effect on short-term weight loss Favorable changes in visceral abdominal fat, total body fat and biomarkers can occur even without weight reduction  Weight loss enhances these improvements

47. Dose Response Church et al. (2007) evaluated effect of varying exercise volumes at fixed intensity (50% VO2max) Sedentary, overweight or obese postmenopausal women randomized to exercise volumes of 50%, 100% or 150% of recommended weekly energy expenditure  Dose-response effect across 3 volumes observed Initial level of fitness may affect the training responses to a set volume of exercise Church TS et al. JAMA. 2007.

48. Benefits of Weight Training and Muscular Fitness Higher levels of muscular strength are associated with significantly better cardiometabolic risk factor profiles, lower risk of all-cause mortality, fewer CVD events, lower risk of developing functional limitations and nonfatal disease

49. Benefits of Weight Training and Muscular Fitness Limited data on dose-response characteristics between muscular fitness and health outcomes or existence of threshold for benefit Muscular fitness can lead to improvements in body composition, blood glucose levels, insulin sensitivity and blood pressure in persons with pre hypertension and stage I hypertension

50. Benefits of Weight Training and Muscular Fitness Resistance training may be effective to prevent and treat “metabolic syndrome” Increases bone mass and bone strength of specific bones stressed  Prevents, slows or even reverses the loss of bone mass in people with osteoporosis Muscle weakness is a risk factor for development of osteoarthritis  Resistance training may reduce chance of developing MSK disorders

51. Benefits of Weight Training and Muscular Fitness May prevent and improve depression and anxiety May increase energy levels and decrease fatigue

52. How to Improve Muscular Fitness Free weights, machines with stacked weights or pneumatic resistance, resistance bands

53. Improving Muscular Fitness Emphasize dynamic exercises involving concentric (shortening) and eccentric (lengthening) muscle actions that recruit multiple muscle groups  Target major muscle groups -- chest, shoulders, back, hips, legs, trunk an arms  Train opposing muscle groups (antagonists) Quads/hamstrings, abdominals/lumbar extensors

54. Improving Muscular Fitness Sets: 2-4 sets of resistance exercises per muscle group Rest Duration: intervals of 2-3 min of rest most effective for achieving increases in muscle strength and hypertrophy

55. Improving Muscular Fitness Selected resistance should permit completion of 8-12 reps per set  Number needed to induce fatigue but not exhaustion Recommend 2-3 times per week of weight training, rest period of 48-72 hours between sessions

56. Improving Muscular Fitness Risk of accidental falls and resulting bone fractures more closely related to decline in muscular power rather than strength Resistance training for older persons should emphasize development of power  Completing 3 sets of 8-12 reps at very light to moderate intensity effectively increases strength and power and improves balance in older persons

57. Benefits of Flexibility Exercise No consistent link has been shown between regular flexibility exercise and reduction of musculotendinous injuries, prevention of low back pain or DOMS Increased flexibility can improve posture and balance Joint ROM improves transiently after flexibility exercise, chronically after about 3-4 weeks of regular stretching at a frequency of at least 2-3 times per week  May improve in as few as 10 sessions with intensive program

58. Benefits of Flexibility Exercise Holding stretch for 10-30 sec at the point of tightness or slight discomfort enhances joint ROM Repeat each flexibility exercise 2-4 times  Enhancement of joint ROM occurs during 3-12 weeks, at least 2-3 days per week

59. Benefits of Flexibility Exercise Target major muscle-tendon units of shoulder girdle, chest, neck, trunk, lower back, hips, posterior and anterior legs and ankles recommended Most effective when muscle temp is elevated

60. Maintaining Beneficial Effects of Exercise Many physiological changes occur as soon as 1-2 weeks after cessation of exercise training Studies on trained athletes  Decreasing volume, frequency and/or intensity of exercise has little or modest influence on VO2max over periods of several months

61. Maintaining Beneficial Effects of Exercise Williams et al (2006): 6000 runners followed for 7.4 years  Magnitude of increase in abdominal adiposity associated with reduction in training was dose-dependent  More exercise required to improve cardiorespiratory fitness and cardiometabolic health than is required to maintain these these improvements Williams PT et al. Obesity (Silver Spring).2006.

62. Maintaining Beneficial Effects of Exercise Resistance training-induced improvements in muscle strength and power reverse quickly with complete cessation of exercise  Neuromuscular and functional changes seem to be maintained for longer period Intensity is important component of maintaining the effects of resistance training

63. Maintaining Beneficial Effects of Exercise Improvements in joint ROM reverse within 4-8 weeks of cessation of stretching exercise  Variable responses among muscle-tendon groups

64. Prescribing Exercise

65. Emphasize individual choice, preference and enjoyment in prescription -- can achieve current recommendations in many ways Previous exercise experience -- may respond better to vigorous exercise Previously inactive -- may be better-suited for moderate intensity exercise

66. Enhancing Adherence Mode of exercise (aerobic vs. resistance, walking vs. running) has very minimal to no effect on adherence to exercise Supervision by experienced exercise leader can enhance adherence

67. Enhancing Adherence Clarify individual’s motives to exercise Create short-term, realistic goals Start low, go slow Provide written exercise prescription Frequent follow up, activity log Consider referral to PT to get started

68. Enhancing Adherence Community-based interventions Programs incorporating brief advice Use of pedometers, telecommunications and group support Desire for strength, feelings of empowerment, previous exercise experience may increase adoption of and adherence to resistance training among older adults

69. Enhancing Adherence Limited evidence suggests pleasant affective responses to exercise may enhance future exercise behavior  More negative affect reported when exercising above ventilatory threshold  Exercise environments with engaging distractions may ameliorate affective experience and increase adherence

70. Prescribing Exercise Evidence insufficient to recommend for or against behavioral counseling in primary care settings to promote physical activity There is evidence that brief counseling by health care professionals can increase exercise adoption when it incorporates established counseling strategies and techniques  Behavioral strategies: goal setting, social support, reinforcement, problem-solving and relapse prevention

71. Prescribing Exercise Pedometers: popular and effective for promoting physical activity and modest weight loss  Provide inexact index of exercise volume  Quality of steps can often not be determined (speed, grade, duration)

72. Prescribing Exercise Goal of 10,000 steps often cited, but even fewer steps can meet current exercise recommendations Meta-analysis of pedometer use -- increase in 2000 steps per day in participants in RCT who had elevated BP  Associated with modest decrease in SBP (~4mmHg) independent of BMI changes Best to use both steps per minute plus currently recommended durations of exercise  100 steps/min is rough approximation of moderate-intensity exercise Bravata DM et al. JAMA. 2007. Kang M et al. Res Q Exerc Sport.2009.

74. Risks of Exercise Risk of CHD and musculoskeletal complications increase transiently during strenuous physical activity compared with risk at other times Musculoskeletal injury is most common exercise-related complication Type and intensity of exercise seem to be more important factors in incidence of injury Volume of exercise is less important factor in incidence of injury

75. Risks of Exercise Rhabdomyolysis associated with exercise is uncommon, but serious  Disorder resulting from damage to skeletal muscle that can cause acute kidney failure, cardiac arrhythmias and death  Risk is increased in both experienced and novice exercisers who undertake unaccustomed eccentric exercise, particularly under hot ambient conditions

76. Risks of Exercise Heart attack, sudden cardiac death  Can be triggered by unaccustomed vigorous physical exertion Few data support the role of routine diagnostic exercise testing as an effective method for reducing the risk of exercise-related CHD events

77. Exercise Testing No randomized controlled trial that shows that asymptomatic people with a positive exercise treadmill test (ETT) have fewer heart attacks or receive better medical management than those without screening ETT

78. ACSM Exercise Treadmill Testing Low RiskMen < 45 yrs, women < 55 yrs and no more than 1 CAD risk factor No ETT Moderate RiskMen >/= 45 yrs, women >/= 55 or at least 2 CAD risk factors ETT for vigorous exercise High RiskAny signs, symptoms or h/o CV, pulmonary or metabolic disease ETT for moderate or vigorous exercise

79. Special Populations Hypertension: exercise is great way to control blood pressure  Resistance training: lower weight, high reps (avoid valsalva)  Beta blockers -- decrease HR and therefore exercise capacity  BB + diuretics may increase risk for heat illness in hot and humid conditions

80. Special Populations Arthritis:  Modify type of activity to low impact Aquatic, cycling, walking  Start low, go slow  Perform functional activities daily Climb stairs Sit to stand exercises

81. Special Populations Diabetes: exercise is great way to control blood sugar  Must have good blood sugar control before starting exercise regimen  Exercise with partner or under supervision  Be aware of symptoms of hypoglycemia  Post-exercise hypoglycemia can last 48 hrs after exercise Monitor plasma glucose levels Eat carbohydrates as needed

82. Special Populations Other Considerations for Diabetics:  Retinopathy: high arterial pressures can cause retinal detachment; if severe, avoid SBP > 170  Peripheral neuropathy: may have balance and gait abnormalities  Autonomic neuropathy: use RPE to monitor intensity

83. Summary Obesity and sedentary lifestyle on the rise across the US ACSM/AHA Recommendations: 30 minutes of moderate exercise daily, at least 5 days per week Physical and psychological benefits to exercise Cardio, resistance training and flexibility exercises all have health benefits Prescribing exercise: pedometers, reasonable goal-setting, social support Risks of exercise: ETT only in specific settings, MSK injuries most common

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87. Thanks!