Exercise Prescription 運動處方

1. Exercise Prescription 運動處方 許世全教授 香港中文大學 體育運動科學系 香港體適能總會 副主席 • Stanley Sai-chuen HUI • Associate Professor, Dept. of SSPE, CUHK • Fellow, ACSM • Vice-chairman, HKPFA

7. Changes of Physical Fitness

8. Changes of Physical Fitness

9. Effect of 12-week Strength Training

10. Effect Aerobic Ex on VO2max Foss 1998, Fox Ex Physiology, p. 329

11. Benefits of Regular Exercise • Improvements in Cardiovascular and Respiratory Function • Increased maximal oxygen uptake due to both central and peripheral adaptations • Lower minute ventilation at a given submaximal intensity • Lower myocardial oxygen cost for a given absolute submaximal intensity

12. Improvements in Cardiovascular and Respiratory Function (cont’) • Lower heart rate and blood pressure at a given submaximal intensity • Increased capillary density in skeletal muscle • Increased exercise threshold for the accumulation of lactate in the blood • Increased exercise threshold for the onset of disease signs or symptoms (e.g., angina pectoris, ischemic ST-segment depression, claudication)

13. Benefits of Regular Exercise • Reduction in Coronary Artery Disease Risk Factors • Reduced resting systolic/diastolic pressures • Increased serum high-density lipoprotein cholesterol and decreased serum triglycerides • Reduced total body fat, reduced intra-abdominal fat • Reduced insulin needs, improved glucose tolerance

14. Decreased Mortality and Morbidity • Primary prevention (I.e.,intervention to prevent an acute cardiac event) 1. Higher activity and/or fitness levels are associated with lower death rates from coronary artery disease 2. Higher activity and/or fitness levels are associated with lower incidence rates for combined cardiovascular diseases, coronary artery disease, cancer of the colon, and type 2 diabetes

15. Secondary prevention (i.e. interventions after a cardiac event [to prevent another]) 1. Based on meta-analyses (pooled data across studies), cardiovascular and all-cause mortality are reduced in post-myocardial infarction patients who participate in cardiac rehabilitation exercise training, especially as a component of multifactorial risk factor reduction 2. Randomized controlled trials of cardiac rehabilitation exercise training involving post-myocardial infarction patients do not support a reduction in the rate of nonfatal reinfarction

16. Results of Studies Investigating the Relationship Between Physical Activity and Incidences of Selected Chronic Diseases * Few studies, probably less than 5; ** Approximately 5 to 10 studies; *** More than 10 studies.  No apparent difference in disease rates across activity or fitness categories;  Some evidence of reduced disease rates across activity or fitness categories;  Good evidence of reduced disease rates across activity or fitness categories;  Excellent evidence of reduced disease rates across activity or fitness categories, good control of potential confounders, excellent methods, extensive evidence of biological mechanisms, relationship is considered causal.

17. Results of Studies Investigating the Relationship Between Physical Activity and Incidences of Selected Chronic Diseases

18. Results of Studies Investigating the Relationship Between Physical Activity and Incidences of Selected Chronic Diseases

19. Other Health Benefits • Decreased anxiety and depression • Enhanced feelings of well-being • Enhanced performance of work, recreational, and sport activities • Increased ability to perform daily living tasks • Reduced muscle and joint injury risk

20. Other Health Benefits • Improved work performance • Enhanced self-concept and esteem • Improved socialization • Increased energy • Greater resistance to fatigue

21. Physical Fitness Health-related Motor skill-related Cardiovascular endurance 心肺耐力 Muscular strength and endurance 肌肉力量與耐力 Muscular flexibility 肌關節柔軟度 Body composition 身體脂肪百分比 [Neuromuscular Relaxation 肌神經鬆馳程度] Agility敏捷 Balance 平衡 Coordination 協調 Power 肌爆炸力 Reaction time 反應時間 Speed 速度

25. Positive Risk Factors for CHDACSM (2000) Family History • Myocardial infarction, coronary revascularization (bypass surgery) or sudden death before : • the age of 55 years in father or other male first degree relative (i.e. brother or son) • the age of 65 years in mother or other female first degree relative (i.e. sister or daughter) Cigarette smoking • Current cigarette smoker or those who have quit in the last six months Hypertension • Client on Hypertensive medications • Resting SBP > 140 mmHg and/ or DBP > 90 mm Hg • Fasting Glucose • Fasting blood glucose of 110mg/dL (6.1mmol/L)

26. Positive Risk Factors for CHDACSM (2000) Hypercholesterolemia • Total serum cholesterol > 200mg/dL (5.2 mmol/L) or • High density lipoprotein (HDL) < 35mg/dL (0.9 mmol/L) • Low density lipoprotein (LDL) > 130mg/dL (3.4mmol/L) • Client is on lipid lowering medications Obesity • Body Mass Index (BMI) > 25 kg/m2 • Waist girth >= 90 cm (M); >= 80 cm (F) Sedentary Lifestyle • Accumulating less than 30 minutes moderate intensity exercise 3-5 days weekly Negative Risk Factors for CHDACSM (2000) High level of HDL • HDL cholesterol > 1.6 mmol/L (60 mg/dl)

27. Initial Risk Stratification • Low risk • Younger individuals who are asymptomatic and meet no more than one risk factor threshold • Moderate risk • Older individuals (men 45 years of age; women  55 years of age) or those who meet the threshold for two or more risk factors • High Risk • Individuals with one or more signs/symptoms or known cardiovascular, pulmonary, or metabolic disease

28. ACSM Recommendations for:(A) Medical Examination and Exercise Testing Prior to Participation, and (B) Physician Supervision of Exercise Tests Low Risk Moderate Risk High Risk A. Moderate exercise NN NN R Vigorous exercise NN R R B. Submaximal test NN NN R Maximal test NN R R NN - Not Necessary R - Recommended

29. What to DO next ?

31. What is Ex. Prescription ? • An individual program of exercise based on an individual’s level of fitness and health status; should consider exercise intensity, frequency per week , duration, and mode. Fit Unfit Healthy & Well Diseased

32. A Quick Review 1st Exercise Prescription(ACSM, 1978) • 3 – 5 days per week (F) • 60 – 90% of HRmax (I) • 15 – 60 min per session (T) • Rhythmical & aerobic, large muscle activities (running, jogging, cycling …etc.) (T) CV training Fitness improvement Features Sufficient Intensity & T

33. A Quick Review • 1990, the 1st Ex Prescription was revised • Muscular Fitness & Flexibility were added • Recognized moderate ex may have health benefits in addition to CV fitness • 1995, Joint ACSM & CDC statements on revised Ex. Prescription

34. A Quick Review Revised Exercise Prescription(ACSM, 1998) CV Fitness and Body Composition • 3 – 5 days per week (F) • 55/65% – 90% of HRmax (I) , or 40/50% - 85% VO2R / HRR, or 12-14 RPE • 20 – 60 min per session (T) • Rhythmical & aerobic, large muscle activities (running, jogging, cycling …etc.)(T)

35. Rate of Perceived Exertion Scale. (RPE)

36. Revised Exercise Prescription(ACSM, 1998) Strength-Training Guidelines. Mode: 8 to 10 dynamic strength-training exercises involving the body’s major muscle groups. Resistance: Enough resistance to perform 8 to 12 repetitions to near fatigue. (10 to 15 repetitions for older and more frail individuals) Sets A minimum of 1 set. Frequency: At least 2 times per week.

37. Revised Exercise Prescription(ACSM, 1998) Guidelines for Various Strength-Training Programs. Strength Training Program Health fitness Maximal strength Muscular endurance Body building Resistance 8-12 reps max 1-6 reps max 10-30 Reps 8-20 reps near max Sets 3 x 3-6 3-6 x 3-8 x Rest Between Sets* 2 min x 3 min x 2 min x 0-1 min x Frequency (workouts per week)** 2-3 x 2-3 x 3-6 x 4-12 x * Recovery between sets can be decreased by alternating exercises that use different muscle groups. ** Weekly training sessions can be increased by using a split body routine.

38. Revised Exercise Prescription(ACSM, 1998) Flexibility Training Guidelines. • Frequency of Exercise: • 5 to 6 times a week • Intensity of Exercise: • To a point of mild discomfort • Repetitions: • Each exercise be done four or five times, holding the final position each time about 10-30 seconds • Types of stretching • Static:Holding at the point of tension • PNF:Contract / Relax - Using reflexes to your advantage

39. Current RecommendationPA vs Fitness Harvard Alumni Study(Paffenbarger et al., 1978, 1984) • High relationship among exercise amount (KCal/wk), mortality rates and CHD • Those who expended at least 2,000KCal/wk, CHD mortality rate droppedsignificantly

40. Current Recommendation: PA vs Fitness Death Rates and RR for Selected Mortality Predictors, Men, ACLS (Cooper Clinic Study) 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

41. Current Recommendation 1996 U.S. Surgeons’ General Report: Physical Activity and Health (USDHHS / CDC / ACSM) Accumulating at least 30 minutes of any kind of moderate intensity physical activity on most days of the week would effectively reduce the risk of coronary heart disease, type 2 diabetes, hypertension, stroke and some kinds of cancer

42. Previous Recommendation Emphasize on fitness Continuous 20 min / session Emphasize on structured exercise (esp. aerobic ex, strength training, stretching) Emphasize sufficient intensity Current Recommendation Emphasize on PA Any kind of PA At least 30 min Accumulated 30 min Moderate intensity (150 Kcal) Most days of week A Comparison Ex  Activity

43. Advantages of New Guidelines • Easier for inactive individuals • More effective for PA promotion • Health first  then fitness • Good for “BUSY” people • More effective to low overall health cost

44. Problems of New Guidelines • Still a bit vague to many people • What is “accumulate” means? 10+10+10 ? 5 x 6 ? 1+1+1+…etc? • What is most days? How many days exactly ? Give me a simple answer ? • What is “moderate” means ? • What is “any kind” of PA? How about home activities or labor intensive activities during work

45. A 2nd Revision of New Guidelines • An expert panel has been formed by CDC / USDHHS 2005, consensus conf 2006 Atlanta. • Revision were suggested: • Accumulate  at least 10 min / interval • most days?  5 days • Moderate?  heavy breathing yet can talk • Any kind?  as long as you don’t sit • Reinstate the advantages of vigorous ex

46. A 2nd Revision of New Guidelines (Aug 2007) To promote and maintain health, all healthy adults aged 18 to 65 yr need • moderate-intensity aerobic (endurance) physical activity for a minimum of 30 min (accumulated) on five days each week; or • vigorous-intensity aerobic physical activity for a minimum of 20 min on three days each week.

47. A 2nd Revision of New Guidelines (Aug 2007) Combinations of moderate- and vigorous-intensity activity can be performed to meet this recommendation. For example: walking briskly for 30 min twice during the week and then jogging for 20 min on two other days.

48. A 2nd Revision of New Guidelines (Aug 2007) Moderate-intensity aerobic activity, which is generally equivalent to a brisk walk and noticeably accelerates the heart rate, can be accumulated toward the 30-min minimum by performing bouts each lasting 10 or more minutes.

49. A 2nd Revision of New Guidelines (Aug 2007) Vigorous-intensity activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate.

50. A 2nd Revision of New Guidelines (Aug 2007) Every adult should perform activities that maintain or increase muscular strength and endurance a minimum of two days each week