Interval versus Continuous High-Intensity Exercise in Chronic Obstructive Pulmonary Disease Interval training as an alternative modality to continuous exercise in patients with COPD Effects of interval and continuous exercise training on autonomic cardiac function in COPD patients Effects of High Intensity Interval versus Moderate Continuous Training on Markers of Ventilatory and Cardiac Efficiency in Coronary Heart Disease Patients Interval training compared with continuous training in patients with COPD. Interval versus continuous training in patients with severe COPD: a randomized clinical trial. High intensity physical group training in water--an effective training modality for patients with COPD. Effects of 2 Exercise Training Programs on Physical Activity in Daily Life in Patients With COPD Aerobic Exercise Training Improves Right- and Left Ventricular Systolic Function in Patients with COPD Greater Improvement in Cardiorespiratory Fitness Using Higher-Intensity Interval Training in the Standard Cardiac Rehabilitation Setting A pilot study examining the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular risk factors in cancer survivors Effects of high-intensity exercise training in a pulmonary rehabilitation programme for patients with chronic obstructive pulmonary disease. High-intensity interval training vs. moderate-intensity continuous exercise training in heart failure with preserved ejection fraction: a pilot study. Low-volume high-intensity interval training vs continuous aerobic cycling in patients with chronic heart failure: a pragmatic randomised clinical trial of feasibility and effectiveness. Efficacy of a physical exercise training programme COPD in primary care: study protocol of a randomized controlled trial Enhancing exercise tolerance and physical activity in COPD with combined pharmacological and non-pharmacological interventions: PHYSACTO randomised, placebo-controlled study design High-intensity interval training versus moderate-intensity steady-state training in UK cardiac rehabilitation programmes (HIIT or MISS UK): study protocol for a multicentre randomised controlled trial and economic evaluation
Context Exercise training improves quality of life in patients with chronic obstructive pulmonary disease , but many of these patients can not tolerate continuous exercise . The effects of intermittent exercise are not known . Contribution The authors r and omly assigned 100 in patients with chronic obstructive pulmonary disease in a 3-week respiratory rehabilitation program to receive either high-intensity continuous exercise or high-intensity exercise alternating with low-intensity exercise ( interval exercise ) . After 5 weeks , the 2 groups had similar respiratory symptoms in daily activities and 6-minute walking distance , but the interval exercise group adhered better to the exercise protocol . Caution s The study focused on initiation of exercise and not on outpatient or home-based maintenance of exercise . Implication s For pulmonary rehabilitation , interval exercise is as effective as continuous high-intensity exercise and is better tolerated . The Editors Low exercise capacity is an important systemic manifestation of advanced chronic obstructive pulmonary disease ( COPD ) associated with poor health-related quality of life , exacerbations , and death ( 14 ) . Physical exercise , therefore , represents an important element of COPD management ( 5 , 6 ) . If performed under supervision during respiratory rehabilitation , exercise training improves health-related quality of life and may improve prognosis ( 79 ) . Dyspnea and leg fatigue limit the ability of patients with COPD to exercise , and patient response to exercise is highly variable ( 10 ) . It is challenging to find endurable exercise programs that are still effective . Current guidelines recommend endurance exercise at constant and high intensity ( 70 % of maximum exercise capacity ) ( 11 , 12 ) . For example , if a patient achieves 100 watts in an incremental exercise test , workload would be set at 70 watts for the entire exercise session of at least 20 minute 's duration . Strong evidence from r and omized trials shows that patients achieve clinical ly important improvements of health-related quality of life and exercise capacity with a continuous exercise protocol ( 1316 ) . However , patients with severe COPD are often unable to tolerate continuous exercise ( 17 ) , which can be frustrating for them and can limit their long-term adherence to exercise programs . Effective alternatives to continuous exercise are required to offer this important intervention to more patients with COPD . The American Thoracic Society and the European Respiratory Society state , on the basis of 2 r and omized trials ( 18 , 19 ) , that interval exercise may be an alternative . The benefits of interval exercise may be similar to those of continuous training , but this method is associated with less dyspnea ( 11 , 12 ) . Although studies indicated that interval exercise is well tolerated ( 1821 ) , evidence about its effectiveness relative to continuous exercise is inconclusive ; previous trials had method ological limitations and were small ( 22 ) . Because of perceived better tolerability of interval exercise , r and omized trials should be explicitly design ed to show that interval exercise is no less effective ( clinical noninferiority ) ( 22 ) . Thus , the aim of our trial was to assess whether interval exercise is no less effective than high-intensity continuous exercise in patients with severe COPD and whether patient tolerance of the interval exercise protocol is superior to that of continuous exercise . Methods Design Overview We conducted a r and omized , controlled noninferiority trial to compare the effects of interval exercise with those of high-intensity continuous exercise in patients with severe COPD . We previously described the detailed study protocol ( 23 ) and report this trial following the recommendations of the extended Consoli date d St and ards of Reporting Trials ( CONSORT ) statement for noninferiority and equivalence trials ( 24 ) . Setting The trial took place in a public rehabilitation clinic , Klinik Barmelweid , in Aargau , Switzerl and . The ethics committee of the Kantonsspital Aarau , Aargau , Switzerl and , approved the study protocol , and all study participants provided written informed consent . Participants We screened patients admitted to the respiratory medicine unit and included consecutive patients following inclusion criteria similar to those of previous respiratory rehabilitation trials ( 7 ) : COPD as defined by FEV1FVC ratio less than 70 % of predicted , FEV1 less than 50 % of predicted after bronchodilation corresponding to Global Initiative for Chronic Obstructive Lung Disease ( GOLD ) stage III to IV ( 5 ) , and German as first or daily language . Exclusion criteria included cardiovascular , musculoskeletal , or neurologic disorders that inhibited physical exercise or the performance of exercise tests ( 6 ) . We also excluded patients who had received a diagnosis of cancer ( excluding skin cancer ) within the past 2 years and were undergoing treatment . R and omization and Interventions A third party not involved in the execution of the trial ( DatInf GmbH , Tuebingen , Germany ) provided online central r and omization using a computerized minimization procedure , thereby ensuring concealment of r and omization ( 25 ) . Stratification variables were exercise capacity ( 6-minute walking distance < 300 or 300 meters ) , the presence of affective disorders ( Hospital Anxiety Depression Scale scores < or 8) , stability of pulmonary condition ( stable or exacerbation within the last 8 weeks ) , and the need for oxygen at rest ( Pao 2 < 55 mm Hg or 55 mm Hg ) . Patients followed an inpatient respiratory rehabilitation of approximately 3 week 's duration that included 12 to 15 exercise sessions . On weekdays , patients usually participated in 1 exercise session .  Twelve physical therapists worked with an approximately equal number of patients from both treatment groups . Apart from exercise , the rehabilitation program was identical for both groups and included breathing therapy , relaxation therapy , guided walking tours , and patient education ( 23 ) . At discharge , physiotherapists prescribed home-based exercise for each patient . Patients with cycle ergometers at home were instructed to exercise for at least 20 minutes per day . If no cycle ergometers were available , daily walking , swimming , or stair climbing was prescribed . High-Intensity Continuous Exercise Patients r and omly assigned to this intervention exercised on electromagnetically braked cycle ergometers ( Ergometrics 900S , Ergoline , Bitz , Germany ) with a target workload of 70 % or more of maximum exercise capacity ( Figure 1 ) . This exercise protocol has been used in earlier respiratory rehabilitation trials ( 7 ) . To determine maximum exercise capacity , patients pedaled unloaded for 3 minutes at 20 watts to warm up . Then , we used increments of 7.5 watts per minute until patients had to stop because of symptoms or cardiovascular stopping criteria . In each exercise session , patients completed a warm-up period of 2 minutes at 20 % of maximum exercise capacity , high-intensity exercise for 20 minutes , and a run-out phase of 2 minutes ( gradual decrease from 70 % to 0 % ) . If patients could not sustain the workload because of perceived dyspnea ( modified Borg [ 26 ] ratings > 5 on a scale from 0 to 10 ) or because heart rate exceeded safety limits , physical therapists let patients rest for 1 minute before continuing in the assigned phase . If patients had to rest more than twice per session , physical therapists lowered the workload by steps of 10 % of baseline maximum exercise capacity for the following exercise sessions . If workload was too low ( modified Borg ratings < 3 or patients or physical therapists considered the workload to be too low ) , physical therapists increased the workload by steps of 10 % of baseline maximum exercise capacity . Figure 1 . Exercise protocol s. Interval Exercise The target workload for this group was 50 % ( high-intensity intervals ) and 10 % ( low-intensity intervals ) of short-term maximum exercise capacity as determined by a steep ramp test ( 27 , 28 ) . The steep ramp test is an incremental cycle ergometer test in which patients pedal cycle ergometers unloaded for 2 minutes and then at increments of 25 watts every 10 seconds until they can not maintain a pedaling frequency above 50 pedals per minute or their heart rate exceeds the limit set by the normal incremental exercise test . We used the steep ramp test because workload for interval exercise can be underestimated if it is based on normal incremental exercise tests ( 28 ) . Fifty percent of short-term maximum exercise capacity corresponds , on average , to 90 % to 100 % of normal maximum exercise capacity ( 27 ) . We chose a workrecovery ratio of 1:2 that prevents high lactate accumulation and is well tolerated by patients ( 28 ) . In each session , patients had a warm-up period of 2 minutes at 10 % of the short-term maximum exercise capacity and then exercised for 20 minutes alternating between high-intensity intervals for 20 seconds and low-intensity intervals for 40 seconds ( Figure 1 ) . Patients also had a slowdown period of 2 minutes before completing the training session . We adjusted the exercise load for each patient individually if workload was too high or too low as described earlier ; physiotherapists lowered or increased the workload by steps of 10 % of short-term maximum exercise capacity , but the length of intervals remained constant ( 23 ) . Outcomes and Measurements Our primary outcome for effectiveness was the difference from baseline in Chronic Respiratory Question naire ( CRQ ) scores 5 weeks after r and omization as measured by the self-administered German- language version ( 29 , 30 ) with st and ardized dyspnea questions ( 31 ) . The CRQ is a widely used instrument in respiratory rehabilitation and measures dyspnea , fatigue , emotional functioning , and ability to cope with COPD ( 7 , 32 ) . Domain and total ( average of domains ) scores are presented on a Likert-type scale from 1 ( most severe impairment ) to 7 ( no impairment ) . We selected assessment at 5 weeks after r and omization as the primary outcome Underst and ing of what constitutes a training load adequate to induce training effects in patients with chronic obstructive pulmonary disease ( COPD ) is still evolving . The present study investigated whether interval training ( IT ) is effective in terms of inducing measurable improvements in physiological response and compared its effects on exercise tolerance ( ET ) and quality of life to those of continuous training ( CT ) . Thirty-six COPD patients , with a forced expiratory volume in one second of 45±4 % of the predicted value ( mean±sem ) , were r and omly assigned to CT ( exercise at 50 % of baseline peak work-rate ) or IT ( work for 30 s at 100 % of peak work-rate alternating with 30‐s rest intervals ) groups that cycled 40 min·day−1 and 2 days·week−1 for 12 weeks . After training , both groups showed significantly improved ET ( IT , 57±6 to 71±8 W ; CT , 57±5 to 70±6 W ) and total quality -of-life score of the Chronic Respiratory Disease Question naire ( IT , 77±3 to 88±2 ; CT , 78±3 to 93±2 ) . At identical levels of exercise , minute ventilation was significantly reduced ( IT , 35.8±2.5 to 31.7±2.5 L·min−1 ; CT , 36.4±2.7 to 32.5±2.7 L·min−1 ) . The magnitude of improvement in these variables was not significantly different among groups . The present data exp and on the principles of exercise prescription for chronic obstructive pulmonary disease patients by demonstrating that interval training elicits substantial training effects , which are similar in magnitude to those produced by continuous training at half the exercise intensity but double the exercise time Both interval ( IT ) and continuous ( CT ) exercise training results in an improvement of aerobic capacity in patients with chronic obstructive pulmonary disease ( COPD ) ; however , their effects on cardiac autonomic function remains unclear . The aim of our study was to evaluate the effect of a supervised CT vs IT on autonomic cardiac function in COPD patients Background . We tested the hypothesis that high intensity interval training ( HIIT ) would be more effective than moderate intensity continuous training ( MIT ) to improve newly emerged markers of cardiorespiratory fitness in coronary heart disease ( CHD ) patients , as the relationship between ventilation and carbon dioxide production ( VE/VCO2 slope ) , oxygen uptake efficiency slope ( OUES ) , and oxygen pulse ( O2P ) . Methods . Seventy-one patients with optimized treatment were r and omly assigned into  HIIT ( n = 23 , age = 56 ± 12 years ) ,  MIT ( n = 24 , age = 62 ± 12 years ) , or nonexercise control group ( CG ) ( n = 24 , age = 64 ± 12 years ) . MIT performed 30 min of continuous aerobic exercise at 70–75 % of maximal heart rate ( HRmax ) , and HIIT performed 30 min sessions split in 2 min alternate bouts at 60%/90 % HRmax ( 3 times/week for 16 weeks ) . Results . No differences among groups ( before versus after ) were found for VE/VCO2 slope or OUES ( P > 0.05 ) . After training the O2P slope increased  in HIIT ( 22 % , P < 0.05 ) but not in MIT ( 2 % , P > 0.05 ) , while decreased in CG ( −20 % , P < 0.05 ) becoming lower versus HIIT ( P = 0.03 ) . Conclusion . HIIT was more effective than MIT for improving O2P slope in CHD patients , while VE/VCO2 slope and OUES were similarly improved by aerobic training regimens versus controls The aim of this study was to compare the effects of interval training ( 3-min intervals ) with continuous training on peak exercise capacity ( W peak ) , physiological response , functional capacity , dyspnoea , mental health and health-related quality of life ( HRQoL ) in patients with moderate or severe COPD . Sixty patients exercised twice weekly for 16 weeks after r and omisation to interval- or continuous training . Target intensity was 80 % of baseline W peak in the interval group ( I-group ) and 65 % in the continuous group ( C-group ) . Patients were tested by spirometry , ergometer cycle test , cardiopulmonary test and a 12 min walk test . Dyspnoea was measured by the dyspnoea scale from Chronic Obstructive Disease Question naire ( CRDQ ) , mental health by Hospital Anxiety and Depression scale ( HAD ) and HRQoL by the Medical Outcomes Survey Short Form 36 ( SF-36 ) . After training , W peak , peak oxygen uptake ( VO(2 ) peak ) and exhaled carbon dioxide ( VCO(2 ) peak ) increased significantly in both groups , no significant differences between the groups . Minute ventilation ( V(E ) peak ) increased only in the C-group . At identical work rates ( isotime ) VO(2 ) , VCO(2 ) and V(E ) were significantly more decreased in the I-group than in the C-group ( p<0.05 ) . Functional capacity , dyspnoea , mental health , and HRQoL improved significantly in both groups , no difference between the groups . Interval training and continuous training were equally potent in improving peak exercise capacity , functional exercise capacity , dyspnoea , mental health and HRQoL in patients with moderate or severe COPD . At isotime , the physiological response to training differed between the groups , in favour of the interval training Limited information is available regarding the physiological responses to different types of exercise training in patients with severe chronic obstructive pulmonary disease ( COPD ) . The aim of this study was two fold : firstly , to investigate the physiological response to training at 60 % of achieved peak load in patients with severe COPD ; and secondly to study the effects of interval ( I ) versus continuous ( C ) training in these patients . Twenty-one patients with COPD ( mean+/-SD forced expiratory volume in one second : 37+/-15 % of predicted , normoxaemic at rest ) were evaluated at baseline and after 8 weeks ' training . Patients were r and omly allocated to either I or C training . The training was performed on a cycle ergometer , 5 days a week , 30 min daily . The total work load was the same for both training programmes . C training result ed in a significant increase in oxygen consumption ( V'O2 ) ( 17 % , p<0.05 ) and a decrease in minute ventilation (V'E)/V'O2 ( p<0.01 ) and V'E/carbon dioxide production ( V'CO2 ) ( p<0.05 ) at peak exercise capacity , while no changes in these measures were observed after interval training . During submaximal exercise a significant decrease was observed in lactic acid production , being most pronounced in the C-trained group ( -31 % , p<0.01 versus -20 % , p<0.05 ) . Only in the I-trained group did a significant increase in peak work load ( 17 % , p<0.05 ) and a decrease in leg pain ( p<0.05 ) occur . Training did not result in a significant improvement in lung function , but maximal inspiratory mouth pressure increased in both groups by 10 % ( C : p<0.05 ) and 23 % ( I : p<0.01 ) . The present study shows a different physiological response pattern to interval or continuous training in chronic obstruction pulmonary disease , which might be a reflection of specific training effects in either oxidative or glycolytic muscle metabolic pathways . Further work is required to determine the role of the different exercise programmes and the particular category of patients for whom this might be beneficial The aim of this study was to examine the effect of high intensity physical group training in water and on l and for patients with COPD with regard to physical capacity and health related quality of life ( HRQoL ) . A controlled , semi-r and omised study was conducted where 30 patients were r and omised to training either in water or on l and . Thirteen patients constituted a control group . Forty-three out patients , with moderate to severe COPD ( 27w/16 m ) , from two local hospitals in northern Sweden , were included in the study . High intensity physical group training in water ( water group ) or on l and ( l and group ) was performed for 12weeks , three times per week , 45min per session . The control group received no intervention . Pre- and post-intervention , all patients performed incremental and endurance shuttle walking tests ( ISWT and ESWT ) ,  cycle ergometer tests  and  responded question naires about HRQoL ( St. Georges Respiratory Question naire -- SGRQ and SF-36 ) . The patients trained with a mean heart rate of 80 - 90 % of peak heart rate . Both training groups increased the distance walked , i.e. l and group in ISWT ( 25 m ) and water group in ESWT ( 179 m ) . The water group increased the distance in ESWT significantly more that both the l and and the control groups . Both training groups increased the time cycled ( 40 - 85s ) and work load ( 10 - 20W ) in the cycle ergometer test . The control group deteriorated in HRQoL according to total score in SGRQ while the training groups remained constant . The water group improved their activity score in SGRQ and their physical health score in SF-36 and those improvements were significant as compared to the l and and the control groups . In conclusion , high intensity physical group training in water is of benefit for patients with COPD . It was in some areas found to be even more effective regarding improvements in physical capacity and experienced physical health compared to the same kind of training on l and BACKGROUND : The effects of different exercise training programs on the level of physical activity in daily life in patients with COPD remain to be investigated . OBJECTIVE : In patients with COPD we compared the effects of 2 exercise/training regimens ( a high-intensity whole-body endurance- and -strength program , and a low-intensity calisthenics- and -breathing-exercises program ) on physical activity in daily life , exercise capacity , muscle force , health-related quality of life , and functional status . METHODS : We r and omized 40 patients with COPD to perform either endurance- and -strength training ( no. = 20 , mean ± SD FEV1 40 ± 13 % of predicted ) at 60–75 % of maximum capacity ,  or calisthenics- and -breathing-exercises training  ( no. = 20 , mean ± SD FEV1 39 ± 14 % of predicted ) . Both groups underwent 3 sessions per week for 12 weeks . Before and after the training programs the patients underwent activity monitoring with motion sensors , incremental cycle-ergometry , 6-min walk test , and peripheral-muscle-force test , and responded to question naires on health-related quality of life and functional status ( activities of daily living , pulmonary functional status , and dyspnea ) . RESULTS : Time spent active and energy expenditure in daily life were not significantly altered in either group . Exercise capacity and muscle force significantly improved only in the endurance- and -strength group . Health-related quality of life and functional status improved significantly in both groups . CONCLUSIONS : Neither training program significantly improved time spent active or energy expenditure in daily life . The training regimens similarly improved quality of life and functional status . Exercise capacity and muscle force significantly improved only in the high-intensity endurance- and -strength group Abstract Objective : The aim of this study was to investigate the effects of moderate continuous training ( MCT ) and high intensity aerobic interval training ( AIT ) on systolic ventricular function and aerobic capacity in COPD patients . Methods : Seventeen patients with COPD ( 64 ± 8 years , 12 men ) with FEV1 of 52.8 ± 11 % of predicted , were r and omly assigned to isocaloric programs of MCT at 70 % of max heart rate ( HR ) for 47 minutes ) or AIT ( ∼90 % of max HR for 4 × 4 minutes ) three times per week for 10 weeks . Baseline cardiac function was compared with 17 age- and sex-matched healthy individuals . Peak oxygen uptake ( VO2-peak ) and left ( LV ) and right ventricular ( RV ) function examined by echocardiography , were measured at baseline and after 10 weeks of training . Results : At baseline , the COPD patients had reduced systolic function compared to healthy controls ( p < 0.05 ) . After the training , AIT and MCT  increased VO2-peak by 8 % and 9 % and work economy by 7 % and 10 % , respectively ( all p < 0.05 ) . LV and RV systolic function both improved ( p < 0.05 ) , with no difference between the groups after the two modes of exercise training . Stroke volume increased by 17 % and 20 % , LV systolic tissue Doppler velocity ( S ’ ) by 18 % and 17 % and RV S ’ by 15 % after AIT and MCT , respectively ( p < 0.05 ) . Conclusion : Systolic cardiac function is reduced in COPD . Both AIT and MCT  improved systolic cardiac function . In contrast to other patient groups studied , higher exercise intensity does not seem to have additional effects on cardiac function or aerobic capacity in COPD patients PURPOSE : We tested the hypothesis that higher-intensity interval training ( HIIT ) could be deployed into a st and ard cardiac rehabilitation ( CR ) setting and would result in a greater increase in cardiorespiratory fitness ( ie , peak oxygen uptake , ) versus moderate-intensity continuous training ( MCT ) . METHODS : Thirty-nine patients participating in a st and ard phase 2 CR program were r and omized to HIIT or MCT ; 15 patients and 13 patients in the HIIT and MCT groups , respectively , completed CR and baseline and followup cardiopulmonary exercise testing . RESULTS : No patients in either study group experienced an event that required hospitalization during or within 3 hours after exercise . The changes in resting heart rate and blood pressure at followup testing were similar for both HIIT and MCT . at ventilatory-derived anaerobic threshold increased more ( P < .05 ) with HIIT ( 3.0 ± 2.8 mL·kg·−1min−1 ) versus MCT ( 0.7 ± 2.2 mL·kg·−1min−1 ) . During followup testing , submaximal heart rate at the end of stage 2 of the exercise test was significantly lower within both the HIIT and MCT groups , with no difference noted between groups . Peak V˙o2 improved more after CR in patients in HIIT versus MCT ( 3.6 ± 3.1 mL·kg.−1·min−1 vs 1.7 ± 1.7 mL·kg.−1·min−1 ; P < .05 ) . CONCLUSIONS : Among patients with stable coronary heart disease on evidence -based therapy , HIIT was successfully integrated into a st and ard CR setting and , when compared to MCT , result ed in greater improvement in peak exercise capacity and submaximal endurance Purpose The aim of this study was to evaluate the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life , functional capacity and cardiovascular disease risk factors in cancer survivors . Methods Cancer survivors within 24 months post-diagnosis were r and omly assigned into the low-volume high-intensity interval training group ( n = 8) or the continuous low to moderate intensity training group ( n = 8) group for 36 sessions ( 12 weeks ) of supervised exercise . The low-volume high-intensity interval training ( LVHIIT ) group performed 7 × 30 s intervals ( ≥85 % maximal heart rate ) and the continuous low to moderate intensity training ( CLMIT ) group performed continuous aerobic training for 20 min ( ≤55 % maximal heart rate ) on a stationary bike or treadmill . Results Significant improvements ( time ) were observed for 13 of the 23 dependent variables ( ES 0.05–0.61 , p ≤ 0.05 ) . An interaction effect was observed for six minute walk test ( 18.53 % [ 32.43–4.63 ] ES 0.50 , p ≤ 0.01 ) with the LVHIIT group demonstrating greater improvements . Conclusion These preliminary findings suggest that both interventions can induce improvements in quality of life , functional capacity and selected cardiovascular disease risk factors . The LVHIIT program was well tolerated by the participants and our results suggest that LVHIIT is the preferred modality to improve fitness ( 6MWT ) ; it remains to be seen which intervention elicits the most clinical ly relevant outcomes for patients . A larger sample size with a control group is required to confirm the significance of these findings BACKGROUND AND OBJECTIVES The benefits of pulmonary rehabilitation for patients with COPD depend on the intensity of training . Traditional pulmonary rehabilitation programmes ( PRPs ) do not consistently achieve high-intensity training and have variable training effects . This study examined the effects of high-intensity exercise training on cardiac and pulmonary function in COPD patients . METHODS Patients with COPD participated in a 6-week , cardiopulmonary exercise test-based PRP . Spirometry , 6-min walking distance and cardiopulmonary exercise test were used to evaluate cardiopulmonary function , respiratory muscle strength and endurance at rest , during exercise and before and after the programme . Patients were encouraged to complete high-intensity exercise with a targeted training intensity of at least 75 % maximum oxygen uptake ( VO(2 ) ) . RESULTS Thirty-four COPD patients were enrolled into the study ; 16 completed the high-intensity training , 18 did not . At the end of the 12-session PRP , submaximal exercise capacity ( 6-min walking distance , 461.8 + /- 77.2 - 502.7 + /- 66.9 m , P < 0.001 ) improved in both the patients who completed high-intensity training and those who did not . Only the patients who completed high-intensity training had significant improvements in FVC ( 2.47 + /- 0.70 - 2.70 + /- 0.62 L , P = 0.024 ) at rest , maximal exercise capacity ( peak VO(2 ) , 1001.6 + /- 286.4 - 1116.1 + /- 320.4 mL/min , P = 0.020 ) and work efficiency ( 7.3 + /- 1.4 - 8.4 + /- 1.8 mL/min/watt , P = 0.026 ) . There was no statistically significant difference between the two groups in the change in the physiological parameters before and after exercise . CONCLUSIONS Exercise training in a PRP improved submaximal exercise capacity . Only patients who completed high-intensity exercise training showed improvements in maximal exercise capacity , FVC and work efficiency Heart failure with preserved ejection fraction ( HFpEF ) is a major cause of morbidity and mortality . Exercise training is an established adjuvant therapy in heart failure ; however , the effects of high-intensity interval training ( HIIT ) in HFpEF are unknown . We compared the effects of HIIT vs. moderate-intensity aerobic continuous training ( MI-ACT ) on peak oxygen uptake ( V̇o₂peak ) , left ventricular diastolic dysfunction , and endothelial function in patients with HFpEF . Nineteen patients with HFpEF ( age 70 ± 8.3 yr ) were r and omized to either HIIT ( 4 × 4 min at 85 - 90 % peak heart rate , with 3 min active recovery ) or MI-ACT ( 30 min at 70 % peak heart rate ) . Fifteen patients completed exercise training ( HIIT : n = 9 ; MI-ACT : n = 6 ) . Patients trained 3 days/wk for 4 wk . Before and after training patients underwent a treadmill test for V̇o₂peak determination , 2D-echocardiography for assessment of left ventricular diastolic dysfunction , and brachial artery flow-mediated dilation ( FMD ) for assessment of endothelial function . HIIT improved V̇o₂peak ( pre = 19.2 ± 5.2 ml·kg(-1)·min(-1 ) ; post = 21.0 ± 5.2 ml·kg(-1)·min(-1 ) ; P = 0.04 ) and left ventricular diastolic dysfunction grade ( pre = 2.1 ± 0.3 ; post = 1.3 ± 0.7 ; P = 0.02 ) , but FMD was unchanged ( pre = 6.9 ± 3.7 % ; post = 7.0 ± 4.2 % ) . No changes were observed following MI-ACT . A trend for reduced left atrial volume index was observed following HIIT compared with MI-ACT ( -3.3 ± 6.6 vs. + 5.8 ± 10.7 ml/m(2 ) ; P = 0.06 ) . In HFpEF patients 4 wk of HIIT significantly improved V̇o₂peak and left ventricular diastolic dysfunction . HIIT may provide a more robust stimulus than MI-ACT for early exercise training adaptations in HFpEF OBJECTIVES The health benefits of high-intensity interval training in cardiac rehabilitation warrant further research . We compared the effectiveness of low-volume high-intensity interval training vs continuous aerobic exercise training in chronic heart failure . DESIGN / SETTING S Unblinded , two arm parallel design with r and om assignment to exercise interventions in out-patient hospital rehabilitation gym . METHODS Patients with signs of chronic heart failure and ejection fraction < 45 % , ( mean age : 59.1 years ( st and ard deviation ( SD ) 8.6 ) ; 3 women ) completed 6 months of exercise using continuous aerobic exercise training ( n = 9 ) or high-intensity interval training ( n = 8) . Cardiorespiratory fitness was determined during cycle ergometry using respiratory gas exchange analysis .  Functional capacity was assessed via sit-to-st and and gait speed . Quality of life was assessed using the MOS Short-Form 36 and Minnesota living with heart failure question naires . Cardiac autonomic regulation was assessed using Heart Rate Variability . RESULTS Analysis of Covariance revealed significant time effects but no group × time interactions for exercise and functional capacity outcomes . Peak oxygen uptake ( VO2peak ) improved by a mean of 14.9 % ( SD 16.3 % ) from baseline and by 22 % ( SD 28.3 ) at ventilatory threshold in both groups . Sit-to-st and ( 11.9 ( SD 11 % ) ) and gait speed ( 16.0 ( SD 19 % ) ) improved similarly in both groups . No changes in quality of life or heart rate variability were noted . Training adaptations in high-intensity interval training were achieved despite a significantly reduced time commitment and total work volume compared to continuous aerobic exercise training . CONCLUSION Low-volume high-intensity interval training is a feasible and well tolerated training modality in cardiac rehabilitation setting s , but is not more effective than continuous aerobic exercise training Background Chronic obstructive pulmonary disease ( COPD ) is recognized as a systemic illness with significant extra-pulmonary features , such as exercise intolerance and muscle weakness . Pulmonary rehabilitation has been shown to be very effective in counteracting these consequences in patients with more advanced COPD . However , limited data is available on the efficacy of a physical exercise training programme in patients with mild to moderate COPD in primary care . Furthermore , it is unknown if improved exercise capacity translates into enhanced daily physical activities . The aim of this paper is to describe the design of a r and omized controlled trial to assess the efficacy of a physical exercise training programme in patients with mild to moderate COPD . Methods / design In this r and omized controlled trial situated in the primary care setting , 102 patients with mild to moderate airflow obstruction ( FEV1 ≥ 50 % of predicted ) , dyspnoea and a physically inactive lifestyle will be r and omized to an intervention or control group . The intervention group receives a 4-month physical exercise training programme at a local physiotherapy practice , which includes exercise training , resistance training , breathing exercises and advises on how to increase the level of physical activity . The control group receives usual care , i.e. advises on how to increase the level of physical activity and a sham treatment at a local physiotherapy practice of which no physiological training stimulus can be expected . Primary outcome is functional exercise capacity at 4-months measured on the six-minute walk distance . Secondary outcomes include peripheral muscle strength , physical activity in daily life , health related quality of life , Medical Research Council ( MRC ) dyspnoea score and patients ’ perceived effectiveness . Follow-up measurement will take place at 6 months after baseline . Discussion This will be one of the first studies to evaluate the efficacy of a physical exercise training programme in patients with mild to moderate COPD completely recruited and assessed in primary care . The results of this trial may give a unique insight into the potential of the implementation of an easy , close-to-home rehabilitation programme . Trial registration The Netherl and s National Trial Register NTR1471 Introduction Chronic obstructive pulmonary disease ( COPD ) is associated with exercise limitation and physical inactivity , which are believed to have significant long-term negative health consequences for patients . While a number of COPD treatments and exercise training programmes increase exercise capacity , there is limited evidence for their effects on physical activity levels , with no clear association between exercise capacity and physical activity in clinical trials . Physical activity depends on a number of behaviour , environmental and physiological factors . We describe the design of the PHYSACTO trial , which is investigating the effects of bronchodilators , either alone or with exercise training , in combination with a st and ardised behaviour-change self-management programme , on exercise capacity and physical activity in patients with COPD . It is hypothesised that bronchodilators in conjunction with a behaviour-change self-management programme will improve physical activity and that this effect will be amplified by the addition of exercise training . Methods and analysis Patients are being recruited from 34 sites in Australia , New Zeal and , the USA , Canada and Europe . Patients receiving a multicomponent intervention design ed to support behaviour change related to physical activity are r and omised to four treatment arms : placebo , tiotropium , tiotropium+olo date rol , and tiotropium+olo date rol+exercise training . The primary outcome is improvement in exercise capacity after 8 weeks , measured by endurance time during a shuttle walk test . The secondary outcome is improvement in physical activity , including objective accelerometer assessment and patient-reported functioning using the Functional Performance Inventory — Short Form and the novel hybrid PROactive instrument . Additionally , the influence of moderating variables ( ie , factors influencing a patient 's choice to be physically active ) on increases in physical activity is also explored . Ethics and dissemination The study has been approved by the relevant Institutional Review Boards , Independent Ethics Committee and Competent Authority according to national and international regulations . The findings of the trial will be disseminated through relevant peer- review ed journals and international conference presentations . Trial registration number NCT02085161 Introduction Current international guidelines for cardiac rehabilitation ( CR ) advocate moderate-intensity exercise training ( MISS , moderate-intensity steady state ) . This recommendation pre date s significant advances in medical therapy for coronary heart disease ( CHD ) and may not be the most appropriate strategy for the ‘ modern ’ patient with CHD .  High-intensity interval training ( HIIT ) appears to be a safe and effective alternative , result ing in greater improvements in peak oxygen uptake ( VO2 peak ) . To date , HIIT trials have predominantly been proof-of-concept studies in the laboratory setting and conducted outside the UK . The purpose of this multicentre r and omised controlled trial is to compare the effects of HIIT and MISS training in patients with CHD attending UK CR programmes . Methods and analysis This pragmatic study will r and omly allocate 510 patients with CHD to 8 weeks of twice weekly HIIT or MISS training at 3 centres in the UK .  HIIT will consist of 10 high-intensity ( 85–90 % peak power output ( PPO ) ) and 10 low-intensity ( 20–25 % PPO ) intervals , each lasting 1 min . MISS training will follow usual care recommendations , adhering to currently accepted UK guidelines ( ie , > 20 min continuous exercise at 40–70 % heart rate reserve ) . Outcome measures will be assessed at baseline , 8 weeks and 12 months . The primary outcome for the trial will be change in VO2 peak as determined by maximal cardiopulmonary exercise testing . Secondary measures will assess physiological , psychosocial and economic outcomes . Ethics and dissemination The study protocol V.1.0 , date d 1 February 2016 , was approved by the NHS Health Research Authority , East Midl and s — Leicester South Research Ethics Committee ( 16/EM/0079 ) . Recruitment will start in August 2016 and will be completed in June 2018 . Results will be published in peer- review ed journals , presented at national and international scientific meetings and are expected to inform future national guidelines for exercise training in UK CR . Trial registration number NCT02784873 ; pre- results
The effects of HIIT appear to be comparable to those of continuous exercise in relation to functional and cardiovascular responses .
OBJECTIVE To evaluate the effects of high-intensity interval training ( HIIT ) , in comparison with those of continuous exercise , on functional capacity and cardiovascular variables in patients with COPD , through a systematic review and meta- analysis of r and omized controlled trials .