Principles Of Exercise Prescription …… Art and Science

1. Principles Of Exercise Prescription……Art and Science David Arnall, Ph.D., PT

2. General Principles : • Mode of exercise • Intensity of exercise • Duration of exercise • Frequency of exercise • Rate of progression

3. The general parameters of exercise prescription hold true for individuals who are healthy as well as those patients who have disease pathology. However, there must be some special considerations for those that have disease.

4. Some Acute & Chronic Disease Pathologies Of Concern • Cardiac Disease - MI’s, CAD, IHD • Vascular Disease - PVD, HTN, Stroke Arteriosclerosis, Atherosclerosis

5. Cancer • Metabolic Disease - Diabetes, Neuro-Endocrine Disorders

6. Patient’s With Pathology • Exercise is not prescribed for these individuals until the patient has undergone a graded exercise stress test (GXT) under the direction of their physician.

7. Graded Exercise Tests • Low Level Graded Exercise Test • Regular Graded Exercise Test Some examples ……...

8. Low Level Exercise Stress Test Stage Speed Grade Dur. METS I 1.7 mph 0 % 3 min 2.3 II 1.7 mph 5 % 3 min 3.5 III 1.7 mph 10 % 3 min 4.6 IV 2.5 mph 12 % 3 min 6.8

9. The low level GXT is given to patient’s with significant cardiac damage and who have an exercise capacity lower than 8 METs

10. Bruce Protocol GXT Stage Speed Grade Dur. I 1.7 mph 10 % 3 min II 2.5 mph 12 % 3 min III 3.4 mph 14 % 3 min IV 4.2 mph 16 % 3 min V 5.0 mph 18 % 3 min VI 5.5 mph 20 % 3 min

11. Modified Bruce Protocol GXT Stage Speed Grade Dur. I 1.7 mph 0 % 3 min II 1.7 mph 5 % 3 min III 1.7 mph 10 % 3 min IV 2.5 mph 12 % 3 min V 3.4 mph 14 % 3 min VI 4.2 mph 16 % 3 min VII 5.0 mph 18 % 3 min

12. USAFSAM GXT Stage Speed Grade Dur. I 2.0 mph 0 % 3 min II 3.3 mph 0 % 3 min III 3.3 mph 5 % 3 min IV 3.3 mph 10% 3 min V 3.3 mph 15% 3 min VI 3.3 mph 20% 3 min

13. Question ? • Are the same aerobic activities appropriate for both the cardiac patient and the healthy individual ?

14. Answer • No !! Cardiac patients have some special concerns such as : • Intensity of the exercise • Static and dynamic balance • Syncope and falling • Degree of cardiovascular pathology • Medications

15. The Exercise Prescription

16. Mode of Exercise • Any activity : • that uses large muscle groups • that is rhthymic • that is sustained below the patient’s anaerobic threshold for 15-60 minutes

17. biking light rowing rebounding ballroom dance walking water aerobics nordic track slow jogging slow jarming skating slow wogging Exercise Mode - Aerobic

18. MET Equivalents • Archery : 4 METs • Canoeing & Rowing : 6-8 METs • Cycling : 5 - 8 METS • Ballroom Dancing : 5 - 9 METs • Fishing : 4 - 6 METs • Golf : 4 - 7 METs

19. Hiking & Walking : 4 - 8 METs • Judo & Tae Kwon Do : 10 - 16 METs • Raquetball : 8 - 14 METs • Rope Jumping : 9 - 12 METs • Rebounding : 6 - 10 METs • Shuffleboard : 3 - 4 METs

20. Ping Pong : 3 - 6 METs • Tennis : 4 - 12 METs • Swimming : 4 - 12 METs • Sailing : 4 - 9 METs • Running 12 min/mile : 9 Mets • Running 10 min/mile : 11 METs • Running 8 min/mile : 13 - 15 METs

21. The various modes of exercise must be specifically tailored to the patient’s physical needs such as : • aerobic work capacity • physical condition & disease state • availability of equipment • patient’s interest & family support

22. Intensity Of Exercise • Exercise intensity is calculated from the results of the GXT Some examples …...

23. The GXT Report Should Have • Resting heart rate • Maximum ex. heart rate • Resting blood pressure • Maximum ex. blood pressure • Maximum METs achieved

24. How Do I Use The GXT Data ? • Use the Modified Karvonen’s Formula to set the training exercise heart rate or the training exercise blood pressure for the population with pathology.

25. The Karvonen Formula Karvonen’s Formula to determine target exercise heart rate was: (HRmax - HRrest) x(.6 - .8) + HRrest This formula needs to be modified for use in diseased populations.

26. The target exercise heart rate should look like this for special populations: (HRmax - HRrest) X[.4 - .8 + Max METs/100]+ HRrest The bracketed portion of the formula containing the Max METs value is called the Activity Fraction.

27. Advantages Of This Modified Karvonen’s Formula • Advantage # 1 : The modified Karvonen’s Formula has a low starting activity fraction to accommodate exercising patients with cardiac disease.

28. Advantage # 2 : The adjusted target heart rate for the patient with disease is calculated on the heart rate, blood pressure and Max METs achieved during the symptom limited GXT .

29. What Is A Symptom Limited GXT ? • A symptom limited GXT is a stress test in which the physician recorded the onset of symptoms (angina, ST segment depression) at the specific heart rate, blood pressure and stage of the GXT.

30. What value is a symptom limited GXT to the Exercise Specialist ? • It provides a maximum exercise HR and BP at which significant signs and symptoms of ischemia begin to appear.

31. All exercise prescriptions are written using the modified Karvonen’s Formula to insure that the patient’s exercise training intensity is significantly lower than the maximum symptom limited exercise HR & BP values avoiding the onset of myocardial ischemia.

32. However………... Seldom does the prescription ever have all of the ideal data!!

33. So ……... How do I write the exercise prescription with only part of the GXT information ?

34. What If……... • Only the blood pressure data is available : • Max. Exercise Systolic BP = 180 mm Hg • Resting Systolic BP = 88 mm Hg Target Ex. Systolic BP = (180-88) x (.6) + 88 = 143 mm Hg

35. What If……... • Only the heart rate data is available : • Max. Ex. HR = 140 BPM • Rest HR = 80 BPM Target Ex. HR = (140 - 80) x (.6) + 80 = 116 BPM

36. What If……... • Only the Max METs data is available : • Max METs Achieved = 7 METs Ex. MET level = 7 METs x (.6 + 7/100) = 4.69 METs

37. What Is A MET ? • A MET is a metabolic equivalent and has the value of : 3.5 ml O2/Kg/min

38. So…... • If I am performing a 10 MET activity, the oxygen utilization for this activity is : 10 METs x 3.5 = 35 ml O2/Kg/min

39. Examples…... • A MET is a measure of energy cost for a particular activity. • Fishing In A Stream = 5-6 METs • Social Dancing = 6-9 METs • Touch Football = 6-10 METs • Scuba Diving = 10-12 METs

40. METs can be a useful measure for a variety of calculations particularly in terms of helping patients to understand physical work capacity (VO2 = ml/Kg/min measurements) or in terms of loosing weight (see next slide).

41. The ACSM recommends minimal thresholds of 300 kcals per exercise session performed 3 days/week or 200 kcals per exercise session performed 4 days/week.

42. This minimum recommendation suggests that exercise prescription target a weekly exercise caloric expenditure of about 1,000 kcals.

43. For optimal results in physical fitness, the ACSM recommends bringing the weekly caloric expenditure up to 2,000 kcals as health and fitness permits.

44. How Can I Transform METs Into Calories Expended ? Kcal/min = (METs) x 3.5 x (Weight in Kg) 200

45. Problem …... Goal : To expend 1,000 Kcals/wk Ex. : Walking @ 3.5 mph (6.1 METs) Weight : 70 Kg (154 lbs.) (6.1 x 3.5) x 70 = 7.47 kcals/min 200

46. Practical Application - Prob. # 1 Take 1,000 kcals/week = 134 min/week 7.47 kcals/min • Prescription : 45 min per day/3 days/week 33 min per day/4 days/week 27 min per day/5 days/week 22 min per day/6 days/week 19 min per day/7 days/week

47. Problem # 2 • Goal : To expend 2,000 Kcals/wk • Ex. : Walking @ 3.5 mph = 6.1 METs • Weight : 127 Kg ( 279 lbs.) (6.1 x 3.5) x 127 = 13.6 kcal/min 200

48. 2,000 kcals/week = 148 min ex./week 13.5 kcals/min Prescription : 49 min of exercise 3 days/week 37 min of exercise 4 days/week 30 min of exercise 5 days/week 25 min of exercise 6 days/week 21 min of exercise 7 days/week

49. Duration of Exercise • Duration of exercise should ideally be between 15 - 60 minutes

50. If the patient is unable to perform 15 minutes of steady state exercise, break the time into two 7-8 minute stages.