RETRAINING OBSTRUCTIVE PULMONARY DISEASE SUBJECTS: From theory to practice

1. RETRAINING OBSTRUCTIVE PULMONARY DISEASE SUBJECTS:From theory to practice

3. COPDChronic Obstructive Pulmonary Disease Permanent and irreversible bronchial obstruction ? chronic hypoxemia  In 2020: probably 3rd cause of mortality in the world From a clinical point of view: Main symptom: dyspnea Very poor respiratory function (permanent) obvious and high exercise intolerance Temps au moment où cette diapo arrive: 20 min 30 sTemps au moment où cette diapo arrive: 20 min 30 s

4. Physical Activity and COPD: not evident at all ! 2 main hurdles : PA ? increased breathlessness to be avoided in dyspneic individuals PA does not change respiratory function so,

5. Major changes In ten years, many works have improved our understanding of the COPD/exercise interface : Exercise tolerance is not only linked to COPD severity COPD muscle shows important abnormalities Quantitative aspect (low muscle mass) Qualitative aspect (muscle structure) Functional consequences Metabolic aspect: the muscle impairments are not linked with insufficient O2 delivery

6. WHAT IS THE CONSEQUENCE ? Reminder of reasons in favor of PA avoidance Poor exercise tolerance due to pulmonary function impossible to improve it (chronic disease) exercise induces dyspnea worsening

7. The main key… To prove that muscle impairment is responsible for early dyspnea

8. COPD MUSCLE STRUCTURE Less fat free mass Loss of maximal force Predictive of peak V'O2

9. Localized muscle endurance Interest of localized exercise: Muscle evaluation without cardiorespiratory limitation Exercise with adequate O2 supply Despite this: Endurance time (Tlim) ?

10. Muscle structure abnormalities: typology

11. Muscle structure abnormalities Decreased activity of oxidative enzymes in COPD Maltais et al, Am J Respir Crit Care Med, 1996. Citrate synthase, HADH Normal activity of glycolytic enzymes: LDH, HK, PFK Explains excessive anaerobic contribution during exercise (localized or general)…

12. Excessive anaerobic contribution – localized exercise

13. Excessive anaerobic contribution – localized exercise

16. Muscle oxidative stress evidence COPD tested in local muscle exercise conditions (quadriceps) Assessment of oxidative stress (TBARs)

17. Muscle impairment occurs before any problem in O2 supply

18. Muscle impairment occurs before any problem in O2 supply

19. Muscle impairment occurs before any problem in O2 supply

20. Consequences for exercise adaptations Decreased aerobic pathway for a given exercise intensity Abnormal, excessive anaerobic contribution

23. SYNTHESIS PRIME PATHOLOGY: DYSPNEA due to respiratory impairment SECONDARY PATHOLOGY: dyspnea due to respiratory center hyper activation Deconditioning consequence Muscle dysfunction DYSPNEA MANAGEMENT : Fight against prime pathology (medical treatment) Subject RECONDITIONING = fight against secondary pathology

24. AIMS OF EXERCISE TRAINING Fight against Deconditioning and muscle dysfunction : cardio respiratory peripheral To solve problems due to prime and secondary pathology

25. A.P.A. JUSTIFICATION PRIME PATHOLOGY: Medical and paramedical management Treatment stabilisation and optimization SECONDARY PATHOLOGY : EPSA teacher directly concerned Work on relationship between Metabolic effects physical practice and Health increase Decreased dyspnea so increased quality of life

26. BASIC KNOWLEDGE NEEDED TO OPTIMIZE A.P.A. Good adaptation of exercise testing Methodological basis of individualization Exercise tests too often done incorrectly dyspnea measurement (diagnosis and evaluation) Optimal training intensity Field test development Retraining follow-up

27. ADAPTED EXERCISE TESTING Basic principle : Individualize on standardized basis Main principles: Continuous test Progressively increased Step duration = 1 min Total test duration = about 10 min after warm-up so imperative individualization of load increment

28. WHY INDIVIDUALIZATION ? Initially, exercise inadaptation are proportional to pathology severity Most of the time : exercise testing too short impossible ventilatory threshold assessment No maximal exercise test (RER<1.10) Bad interpretation of subject ability to perform exercise and training programing

29. HOW INDIVIDUALIZE ? STEPS: Calculation of theoretical max. O2 uptake Correction according FEV1 (% theoretical) Calculation of expected maximal power output by converting in watts (remove 250 ml/min and divide by 10.3) Warm-up = 20 % of expected Pmax during 3 min Step = 8% of expected Pmax (every minute)

30. CALCULATION OF THEORETICAL VO2max

31. EXAMPLE Man: 38 years, 80 kg, 1.76 m and FEV1 = 65% of theoretical value V'O2max théor. (formula b)=2865 ml.min-1 Corrected V'O2max =2865 x 0,65= 1862 ml.min-1 Expected Pmax =(1862-250)/10,3 = 156 watts SO: Warm-up = 156 x 0,2 = 31 watts Increment = 156 x 0,08 = 12,5 watts per minute

32. EXAMPLE FOR EXPECTED Pmax =156 WATTS

33. MEASUREMENT OF VENTILATORY THRESHOLD DURING INCREMENTAL EXERCISE/ Recording V’O2 and V’CO2 (breath-by-breath) Averaging every 10 seconds Computation of V’O2 / V’CO2 relationship

36. Interest of individualization at ventilatory threshold directly function of aerobic physical fitness Individualization / real capacities Before excessive hyperventilation Very well tolerated (no or few dyspnea) Efficient to induce training effects Easy learning of individualized practice Usable in current life If impossible to measure ? dyspnea threshold

37. DYSPNEA by Visual Analog Scale (VAS)

38. DYSPNEA THRESHOLD(Visual Analog Scale – VAS)

40. RATIONALE Disadvantage of individualized training : Regular cardio respiratory evaluation => cost ? Solution : Adapted field test  One of the most popular : 6 or 12 min walking test

41. 6 MINUTE WALKING TEST From Cooper test (12 min) shortened until 6 min Linearity of walking pace (12 = 2 x 6) highly simple Excellent reproducibility If correct learning Without verbal encouragement alone Very well correlated with V'O2sl

42. ADAPTED TO ASSESS TRAINING EFFECTS ? NOT YET STUDIED : Relationship with physical fitness = Not sufficient (correlation ? cause to effect relationship) QUESTION : 6 min walking test is it able to identify physiological modifications due to retraining ? Protocol : study of relationships Aerobic physical fitness and 6 min WT Before and after retraining

43. 6MWT and training effects

44. RELATIONSHIP 6MWT AND VENTILATORY THRESHOLD

45. RELATIONSHIP 6MWT AND VO2sl

46. PHYSICAL FITNESS PREDICTION For VO2 sl (r=0.95): For ventilatory threshold (r=0.91): In addition: After training measured and calculated values non different (diff. Mean = 0.06 l.min-1)

47. 6 MIN WALKING TEST Sensitive to physical fitness variation: ventilatory threshold +++++ Max O2 uptake +/- Possible aerobic physical fitness prediction Stables relationships throughout training Valid equations even after training

50. OPTIMIZATION WHICH INTENSITIES ?

51. STATE OF THE ART Works of literature : No consensus Most of the time : Training intensities based on % reserve heart rate [ HRrest + (HRmax - HRrest) % ] Interest : Simplicity of realization

52. PROBLEM : NEED TO CERTIFY EFFECTIVENESS OF RESULTS Relevance ??? No consideration of cardio respiratory fitness standardization is in opposition to individualization QUESTION : Which method lead to best results ?

53. -- INTEREST -- Stays in specialized centers : More and more shortened  SO : High need to be as efficient as possible That is Obtain best results every time In a minimum amount of time

54. PROTOCOL 2 groups studied : Trained at the same absolute HR, but : 1 gpe at ventilatory threshold (individualization) 1 gpe at 50% of reserve HR (standardtion )training at the same frequency and duration Blind final evaluation

55. RESULT 1 RESERVE HR NO RELEVENT INTENSITY

57. Reserve HR : Random results Under- or over-estimation of efficient intensities CONCLUSION

58. GENERAL RESULTS Exercise adaptations : Better exercise tolerance : dyspnea decrease Restoration on self confidence Enhancement of quality of life : General well-being, emotional state (Ojanen et al, 1993) durable effect (Dekhuijzen et al., 1990)  Improvement of psychological state : Never linked with resting pulmonary function Always related to possible physical activity amount linked to functional state

59. Main results Validated in international literature: Original studies and meta-analysis Evidence-based medicine: rating the strength of evidence

60. Respiratory rehabilitation based on A.P.AFrom:Joint ACCP/AACVPR Evidence-Based Guidelines. Chest, 1997, 112:1363:96.Fabbri and Hurd; GOLD Scientific Committee. Eur Respir J, 2003, 22: 1-2. Unique technique assessed with grade A for: ? breathlessness ? health-related quality of life ? depression and anxiety associated with COPD ? hospitalization number and duration Amazingly better exercise tolerance ? exercise capacity ? dyspnea for a given exercise intensity Grade B for: Improved survival

62. Effects on ventilatory requirement ______ Varray, Mercier, Préfaut. Int. J. Rehab. Res., 1995, 18: 297-312.

63. VENTILATORY REQUIREMENT Ventilation decrease for a given exercise intensity: Increased ventilatory comfort for any exercise intensity Decreased respiratory cost (dyspnea ?) SO: more O2 for exercising muscles : Exercise capacity increased Better exercise efficiency

65. BREATHING PATTERN

66. BREATHING PATTERN MODIFICATION

67. Individualization versus standardization

68. Individualization versus standardization (breathing pattern)

69. Effects on muscle dysfunction – localized exercise

70. Effects on muscle dysfunction – localized exercise

71. Effects on muscle dysfunction – general exercise

72. Muscle efficiency

73. COST/EFFECTIVENESS RELATIONSHIPS + work of Trautner (Eur. Resp. J., 1993) - asthma and health management : For 1 DM (cost), 5 DM saved for public health economy