Exercise Objectives. Lecture Objectives. Contrasting Approaches and Techniques of Exercise in Pulmonary Rehabilitation

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1 Contrasting Approaches and Techniques of Exercise in Pulmonary Rehabilitation Mark W. Mangus, Sr., BSRC, RRT, RPFT, FAARC Pulmonary Rehabilitation Coordinator Christus Santa Rosa Medical Center San Antonio, Texas Lecture Objectives Review Purpose/Objectives of Exercise Apply Objectives to needs of the Pulmonary Patient Review ACCP/AACVPR Evidence-Based Guidelines for Pulmonary Rehabilitation (1997) Special Report: Pulmonary Rehabilitation. Joint ACCP/AACVPR Evidence-Based Guidelines, Ries, A., et,al, Chest, 112:5, Nov.1997: Discuss specific exercise applications and techniques Summary and Recommendations Exercise Objectives Increase muscle strength Increase ability to sustain activity (endurance) Increase/improve mobility Improve/Control breathlessness ADDITIONAL BENEFITS Improved body mass - weight Improved physical function Improved wellbeing and quality of life Reduced symptoms, exacerbations & hospitalizations Improved survival? 1

2 Types of Exercises Upper Extremity Exercises Lower Extremity Exercises Ventilatory Muscle Training ADDITIONAL EXERCISE APPLICATIONS Activities of Daily Living Functional exercises to perform specific tasks Specific Exercise Considerations Exercise must fit patient s capabilities/tolerance alter dynamics of breathing challenge breathing Exercise must not be Arbitrarily limited self-limiting inappropriate to the objectives/patient needs What we know People with advanced pulmonary disease develop increasing intolerance to exertion due to increasing ventilatory inadequacy dynamic hyperinflation hypoxia acidemia increased energy demand to breathe AND move loss of body mass lean - muscle fat stores - reserve energy 2

3 What we know Increased intolerance of exercise fosters an increasingly sedentary lifestyle, further perpetuating decreased tolerance of exertion. Energy cost to do physical work increases due to decreased muscle strength and endurance. Systems fail as critical thresholds are crossed in overall process of decline. What we know Improved exercise tolerance can improve breathing-related symptoms. Improved breathing does not result from significantly altered ventilatory mechanics. Improved breathing is the result of reduced ventilatory demand secondary to reduced oxygen demand and carbon dioxide production (per unit of work). desensitization to dyspnea What we know From a pathophysiologic standpoint, exertioninduced windedness does not pose injurious risk to patients with advanced lung disease. Windedness represents more of a limit to comfort and psychological wellbeing than necessarily to one s ability to engage in significant physical exertion. Overcome physical and psychological limits imposed by windedness = increased tolerance of exertion = improved function and condition. 3

4 What we know Exercise conditions and considerations of those with advanced pulmonary disease are significantly different from those for healthy individuals those with other diseases Guidelines for healthy individuals must be modified to fit the conditions and objectives of those with advancing pulmonary disease. What we know Guidelines for those with other diseases must not be applied directly to those with advancing pulmonary disease. Specifically, guidelines for those with primarily cardiac disease are inappropriate for those with pulmonary disease in the absence of primary cardiac limitations. (Yet, cardiac disease guidelines are most frequently mis-applied to those with advanced pulmonary disease, compromising ability to achieve optimal outcomes.) What we know Failure of patients to achieve their maximum physical and functional potential is the result of inability to master improved control of breathing. desensitization to windedness not achieved inadequate conditioning to alter existing, but alterable limits. limitations imposed by others - professional and lay inappropriately selected limits (vital signs, work load, etc.) arising from poor understanding and/or misconceptions. 4

5 What we know Studies of rehabilitative exercise deal with one variety of lung disease - COPD. Sparse study of non-copd exercise programs reveals that restrictive lung diseases pose different limits and challenges to function and conditioning. direct extrapolation of approaches for COPD may not be appropriate for other non-copd (restrictive) lung diseases. What we know Studies show that some exercise applications produce positive change while others do not. Lower extremity exercises produce the greatest degree of improvement in symptoms, condition and function. Upper extremity exercises, while producing improvement in symptoms, produce minimal improvement in condition and overall function. Ventilatory muscle training produces minimal change in symptoms and little measurable change in condition or function, despite significant changes in airflow. Lower extremity exercises do not result in improved measures of mechanical lung function do not produce evidence of adverse outcome. do result in patients improved capacity for ambulation. do result in improved tolerance of submaximal tasks involving muscles of ambulation. 5

6 Lower extremity exercises Improvement is related to exercise type cycle ergometry walking exercise intensity > intensity = > strength exercise duration > duration = > endurance exercise frequency > frequency = > overall rate and degree of conditioning Lower extremity exercises Measures to determine baseline condition and effect of conditioning interventions timed walking tests six-minute walk test shuttle walk test incremental treadmill and stationary bicycle protocols constant work rate treadmill and cycle studies Lower extremity exercises All studies demonstrate improved exercise tolerance and conditioning. Pitfalls to objectivity of evidence include exercises are effort and practice dependent training effect cannot be reliably separated from motivational influences. objective measures - aerobic enzyme levels derived from muscle biopsies, VO 2, V E are mixed and show no consistent evidence of change. 6

7 Lower extremity exercises Conclusions from ACCP/AACVPR guidelines for lower extremity exercise benefit: Studies demonstrate relatively convincing evidence of physiologic training effect. Conditions producing evidence of training effect were confined to studies that incorporated supervised exercise programs. Little (convincing) evidence is available to demonstrate benefit of unsupervised exercise programs. Evidence yields no firm recommendations for optimal, specific training regimens for COPD. Lower extremity exercises ACCP/AACVPR guidelines conclusions and recommendations for lower extremity exercise There is substantial evidence that lower extremity exercise training should be included in rehabilitation programs for patients with COPD. Benefits may be both physiologic and psychological. However, the optimal specific exercise prescription guidelines for the muscles of ambulation cannot be defined with certainty at this time. A program of exercise training of the muscles of ambulation is recommended as a part of pulmonary rehabilitation for patients with COPD. Lower extremity exercises Unresolved issues for training recommendations Benefits of exercise programs are multifactoral and dependent upon desired goals and benefits. Exercise programs have both physical and psychological benefits. Physiologic - structural and biochemical changes in muscles improved capacity to tolerate a given rate of work improved efficiency of movement Psychological - improved motivation reduced limitation/effect of dyspnea/desensitization antidepressant effects of exercise 7

8 Upper Extremity Exercises do not affect ability to tolerate ambulation. do increase O 2 uptake and CO 2 production due to elevation during exercise. can influence exercise performance by decreasing ventilatory demand during arm work through improved arm endurance. can improve ventilatory contribution of shoulder girdle muscles through improved strength. Upper Extremity Exercises Benefit from arm exercises is related to exercise type ergometry (supported arms) free weight training (unsupported arms) rowing/swimming/canoeing (unsupported arms) dependent upon load > load = > strength correlated highly with intensity > intensity = > greater measurable benefit dependent upon duration > duration = > benefit Upper Extremity Exercises Arm exercises are specific for improved arm function. reduce oxygen uptake for similar workload. produce greater improvement with exercises utilizing unsupported arms as compared to supported arms. produce greater benefit when added to a program of leg strengthening than either exercise alone. are safe. 8

9 Upper Extremity Exercises Measures to determine effect of upper extremity exercise controlled studies aerobic enzyme measurement from muscle biopsy endurance uncontrolled and observational studies of oxygen uptake PFT s (VC, RV, V E ) ventilatory requirements Upper Extremity Exercises Studies demonstrate benefits of arm exercises. increased exercise capacity of arms decreased metabolic and ventilatory demand after training Studies do not support improved physical function from arm exercises alone. Arm cranking is the most common form of arm exercise and most easily standardized. The best form of training remains unknown. Upper Extremity Exercises ACCP/AACVPR guidelines conclusions and recommendations for upper extremity exercise Upper extremity exercises result in increased exercise capacity of the arms and decreased metabolic and ventilatory demand for similar arm work after training. Arm exercises are safe and should be included in rehabilitation programs for patients with COPD. 9

10 Upper Extremity Exercises Areas that warrant further investigation include establish selection criteria for best application determine the effect of arm training on functional outcomes evaluate different forms of arm training with regard to type, duration, frequency and intensity and their effect on outcomes variables determine the effect of intense arm exercise/training on respiratory muscle function Ventilatory Muscle Training (VMT) does not result in clinically significant improvement in measures of lung function does not result in significant reduction of dyspnea, breathlessness when used alone does not result in different outcomes when used in conjunction with lower or upper extremity exercises, compared to those regimens without VMT Ventilatory Muscle Training (VMT) Types of VMT sustained hyperpnea - mode which invokes increase in V E which continues for a prolonged period of time, at or near maximum ventilatory capacity (eucapneic) inspiratory resistance breathing - inspiratory efforts against a threshold resistance in various patterns (IMT - Inspiratory Muscle Training) expiratory resistance breathing efforts against a threshold resistance in various patterns (PEP Positive Expiratory Pressure Breathing) 10

11 Ventilatory Muscle Training (VMT) IMT was selected as the only form of VMT considered for the guidelines sustained hyperpnea requires large apparatus and monitoring for optimal data gathering and is rarely done today according to ACCP/AACVPR panel only inspiratory muscle training (IMT) has the best potential to provide most the consistently reproducible training effect - PI max IMT is the only mode of VMT studied to any degree Ventilatory Muscle Training (VMT) Effects of VMT, if they are to be meaningful and measurable require that VMT be performed at very high intensity. Studies did not show significant training effect from VMT because intensity was never great enough to achieve measurable change. VMT alone has not been shown to significantly alter breathing characteristics associated with dyspnea. Ventilatory Muscle Training (VMT) ACCP/AACVPR guidelines conclusions for ventilatory muscle training Most randomized controlled trials of inspiratory resistance training in patients with COPD do not provide conclusive scientific evidence of benefit. However, many of these studies did not include a sufficient training stimulus to achieve the expected increase in respiratory muscle function. Selected randomized, controlled trials that include adequate training loads (ie, an intensity of at least 30% of PImax) and measured clinical outcomes have showed improvements in dyspnea and/or exercise tolerance with VMT. 11

12 Ventilatory Muscle Training (VMT) ACCP/AACVPR guidelines recommendations for ventilatory muscle training The scientific evidence, at the present time does not support the routine use of VMT as an essential component of pulmonary rehabilitation. However, VMT may be considered in selected patients with COPD who have decreased respiratory muscle strength and breathlessness. Exertional breathing limitations If ventilatory muscles are not significantly deconditioned and VMT is of little help, then what IS effective to deal with exertional breathlessness? Controlled breathing techniques Pursed-lip breathing (PLB) abdominal breathing diaphragmatic breathing Desensitization conditioning Exertional breathing limitations PLB is singularly the most effective maneuver available to control and overcome exertional breathlessness. Abdominal (belly) breathing is arguably better to transfer ventilatory work away from upper chest accessory muscles and down to abdominal muscles and diaphragm (force generated with lower-abdominal muscles is best) Diaphragmatic breathing is very ambiguous and may be different things to different people as compared to abdominal breathing shown not to necessarily produce desired effect when various popular methods are used. ALL people breathe with their diaphragm, whether or not it is the primary muscle of breathing or not. There is only limited direct action that can selectively affect work of the diaphragm. 12

13 Exertional breathing limitations PLB - What does it do? prolongs exhalation by requiring time to empty the lungs against the expiratory resistive threshold allows better/more complete emptying of the lungs splints airways, facilitates better expiratory flow Prevents distal airway collapse and air-trapping slows respiratory frequency by default, due to prolonging effect on expiratory phase thwarts dynamic hyperinflation Exercise monitoring What should be monitored and why? Breathing pattern and work identify and correct deficiencies and abnormalities Oximetry (pulse) continuous versus spot checks identify and correct desaturation Blood Pressure ensure safe range and absence of related symptoms when up or down Exercise monitoring What should be monitored and why? Heart Rate identify arhythmias assess rate - too high/too low pace makers equate with oxygenation for influences on breathing Exercise type, load/intensity, duration assess tolerance adjust as indicated 13

14 Exercise monitoring What factors should limit exercise intensity, duration or type suitability for type of exercise selected inadequacy of interface with selected exercise cardiovascular changes excessive changes in heart rate and/or B/P changes in heart rate and/or B/P accompanied by symptoms uncorrectable desaturation symptoms dizziness nausea Exercise monitoring What factors should not limit exercise type, duration or intensity? inappropriate arbitrary limits on heart rate blood pressure respiratory rate oxygen saturation supplemental oxygen duration and intensity Exercise approach How do we achieve the objectives? Estimate the patient s minimum level of required exertional tolerance based upon lifestyle/adl s. Estimate the relative difference between the patient s current condition and that needed to reach a minimum level of exertional tolerance. Set a tentative schedule of incremental increase in exercise based on the estimated deficit. Assess progress at reasonable intervals and as required, adjust the time to reach the target. 14

15 Exercise approach What about - ventilatory work during exercise? Windedness is an expected response to exertion. Windedness is a goal to be achieved, not a symptom to be avoided. If sufficient windedness is not achieved during exercise, The threshold for breathlessness/dyspnea cannot be increased. Controlled breathing cannot be effectively utilized and mastered. Intervention with supplemental oxygen or increased flow is indicated when windedness is accompanied by desaturation. Windedness from increased ventilatory drive ( ph/ pco 2 ) is better tolerated in the face of adequate oxygen levels (>90%). Exercise approach What about - heart rate during exercise? For most COPD patients, heart rate can often safely rise to as high as 150/min. without danger. Rhythm should be regular, or known AND stable atrial fibrillation or other functional arrhythmia. Patients with COPD are often on medications which have chronotropic affects. Evaluate! Exercise approach What about - heart rate during exercise? Calculated maximum heart rates should not be used exclusively to limit exercise duration or intensity. (i,e; 220-age...) Windedness should be assessed against heart rate. Excessive windedness, especially with desaturation, in the face of an inappropriately low heart rate (< 110/min) at peak tolerable load could be an indication of a rhythm, perfusion or other cardiac limitation. 15

16 Exercise approach What about - blood pressure during exercise? For most patients, blood pressure can rise significantly without posing risk of harm. Systolic < 220 without symptoms (headache, dizziness, pressure in head). Diastolic < 110 without symptoms as listed above. The more deconditioned the patient is the greater will be their blood pressure changes in response to exercise. In general, patients with history of hypertension who are stable pharmacologically, tolerate exertional increases well. Receding blood pressure maximums in response to improved conditioning over time is one of the most frequently observed secondary responses to exercise. Exercise objectives What should exercise objectives include? intensity sufficient to produce desired training effect intensity sufficient to challenge control of breathing a maximum exercise tolerance that exceeds the patient s most demanding daily physical task achieving tolerance of the patient s maximal level of breathing limitation achieving tolerance of the patient s maximal level of exertion achieving oxygenation that will allow maximal exercise performance with a reasonable amount of manageable discomfort an outcome that raises the patient toward his/her highest level of function within his/her fixed limitations Exercise objectives Intensity sufficient to produce desired training effect Duration sufficient to combine with intensity for desired outcome Pitfalls: insufficient intensity insufficient duration Enhancement interval training 16

17 Exercise objectives Intensity sufficient to challenge control of breathing below the threshold of panic, yet with a manageable degree of anxiety Pitfalls: likely the most common pitfall of many exercise approaches stopping the patient too soon into windedness Enhancement often requires significant coaching desensitizing effect to dyspnea/anxiety Exercise objectives A maximum exercise tolerance that exceeds the patient s most demanding daily physical task Pitfalls: perhaps the most common shortfall of approaches just enough approach too often applied misconception about need versus capacity/tolerance Enhancement: greater desensitization to dyspnea greater endurance to sustain higher intensity tasks Exercise objectives Achieving tolerance of the patient s maximal level of breathing limitation raises dyspnea threshold desensitization Achieving tolerance of the patient s maximal level of exertion increases training effect increases overall condition/function 17

18 Exercise objectives Achieving oxygenation that will allow maximal exercise performance with a reasonable amount of manageable discomfort another common shortfall of some approaches achieve 90 % because it is safe just enough approach highest performance observed at saturations > 94 % highest performance not observed at < 94 % - discomfort increases significantly significant improvement in tolerance/comfort at higher intensity workload greater training effect (Casaburi, 2004) Exercise objectives An outcome that raises the patient toward his/her highest level of function within his/ her fixed limitations through applying a more aggressive approach to intensity, duration and oxygenation through greatest training effect through greater desensitization to breathing symptoms/limitations Summary COPD patients, as a group may represent the most poorly understood with regard to exercise objectives, approach and rehabilitative practice. COPD patients have been found least likely to achieve their maximum due to arbitrary limitation. Imposed arbitrary limits are the result of perceptions of risk that do not surface under investigation. Incidence of mishap or injury due to perceived risks is low to non-existent in retrospective study. 18

19 Summary COPD patients can achieve remarkable improvement in condition and function, even with very poor pulmonary function (FEV-1 < 25 % pred.). Evidence is mounting to show that patients achieve a greater level of conditioning IF they are given supplemental oxygen sufficient to raise exercise saturation to greater than 90 %, as compared to settling for 85 % - 90 %. Recent evidence suggests that supporting oxygenation to keep saturation above 94 % produces clinically significant improvement in exercise tolerance and performance as compared to 90 %. (Casaburi, et al; Am Rev Resp Crit Care Med, 1, 2004) Oxygen should be given liberally, BOTH to improve exertional oxygen saturation and comfort. Summary Effectively exercising those who have severe COPD is not for the faint of heart. Health care professionals who engage in exercising those with COPD must have significant understanding about the limitations exhibited by those with COPD and intuition and the skills to apply interventions that effectively change patients physical functional capacity. To achieve maximum function and condition requires an aggressive approach with regard to both conditioning activities and support measures. 19