***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Affect experienced during an exercise session is purported to predict future exercise behaviour . Compared to continuous moderate-intensity exercise ( CMI ) , the affective response to continuous vigorous-intensity exercise ( CVI ) has consistently been shown to be more aversive . The affective response , and overall tolerability to high-intensity interval training ( HIT ) , is less studied . To date , there has yet to be a comparison between HIT , CVI , and CMI . The purpose of this study was to compare the tolerability and affective responses during HIT to CVI and CMI . This study utilized a repeated measures , r and omized , counter-balanced design . Forty-four participants visited the laboratory on four occasions . Baseline fitness testing was conducted to establish peak power output in Watts ( Wpeak ) . Three subsequent visits involved a single bout of a ) HIT , corresponding to 1-minute at ∼100 % Wpeak and 1-minute at ∼20 % Wpeak for 20 minutes , b ) CMI , corresponding to ∼40 % Wpeak for 40 minutes , and c ) CVI , corresponding to ∼80 % Wpeak for 20 minutes . The order of the sessions was r and omized . Affective responses were measured before , during and after each session . Task self-efficacy , intentions , enjoyment and preference were measured after sessions . Participants reported greater enjoyment of HIT as compared to CMI and CVI , with over 50 % of participants reporting a preference to engage in HIT as opposed to either CMI or CVI . HIT was considered more pleasurable than CVI after exercise , but less pleasurable than CMI at these times . Despite this participants reported being just as confident to engage in HIT as they were CMI , but less confident to engage in CVI . This study highlights the utility of HIT in inactive individuals , and suggests that it may be a viable alternative to traditionally prescribed continuous modalities of exercise for promoting self-efficacy and enjoyment of exercise Background — Exercise training reduces the symptoms of chronic heart failure . Which exercise intensity yields maximal beneficial adaptations is controversial . Furthermore , the incidence of chronic heart failure increases with advanced age ; it has been reported that 88 % and 49 % of patients with a first diagnosis of chronic heart failure are > 65 and > 80 years old , respectively . Despite this , most previous studies have excluded patients with an age > 70 years . Our objective was to compare training programs with moderate versus high exercise intensity with regard to variables associated with cardiovascular function and prognosis in patients with postinfa rct ion heart failure . Methods and Results — Twenty-seven patients with stable postinfa rct ion heart failure who were undergoing optimal medical treatment , including & bgr;-blockers and angiotensin-converting enzyme inhibitors ( aged 75.5±11.1 years ; left ventricular [ LV ] ejection fraction 29 % ; & OV0312;o2peak 13 mL · kg−1 · min−1 ) were r and omized to either moderate continuous training ( 70 % of highest measured heart rate , ie , peak heart rate ) or aerobic interval training ( 95 % of peak heart rate ) 3 times per week for 12 weeks or to a control group that received st and ard advice regarding physical activity . & OV0312;o2peak increased more with aerobic interval training than moderate continuous training ( 46 % versus 14 % , P<0.001 ) and was associated with reverse LV remodeling . LV end-diastolic and end-systolic volumes declined with aerobic interval training only , by 18 % and 25 % , respectively ; LV ejection fraction increased 35 % , and pro-brain natriuretic peptide decreased 40 % . Improvement in brachial artery flow-mediated dilation ( endothelial function ) was greater with aerobic interval training , and mitochondrial function in lateral vastus muscle increased with aerobic interval training only . The MacNew global score for quality of life in cardiovascular disease increased in both exercise groups . No changes occurred in the control group . Conclusions — Exercise intensity was an important factor for reversing LV remodeling and improving aerobic capacity , endothelial function , and quality of life in patients with postinfa rct ion heart failure . These findings may have important implication s for exercise training in rehabilitation programs and future studies Background Heart rate recovery ( HRR1 ) immediately after exercise reflects parasympathetic activity , which is markedly attenuated in chronic heart failure ( CHF ) patients . The aim of our study was to examine both continuous and interval exercise training effects on HRR1 in these patients . Design The population study consisted of 29 stable CHF patients that participated at a rehabilitation program of 36 sessions , three times per week . Of the 29 patients , 24 completed the program . Patients were r and omly assigned to interval { n = 10 [ 100 % peak work rate ( WRp ) for 30 s , alternating with rest for 30 s ] } and to continuous training [ n = 14 ( 50%WRp ) ] . Methods All patients performed a symptom-limited cardiopulmonary exercise test on a cycle ergometer before and after the completion of the program . Measurements included peak oxygen uptake ( VO2p ) , anaerobic threshold ( AT ) , WRp , first degree slope of VO2 during the first minute of recovery ( VO2/t-slope ) , chronotropic response [ % chronotropic reserve ( CR ) = ( peak HR - resting HR ) × 100/(220 - age - resting HR ) ] , HRR1 ( HR difference from peak exercise to one minute after ) . Results After the completion of the rehabilitation program there was a significant increase of WRp , VO2p , AT and VO2/t-slope ( by 30 % , P=0.01 ; 6 % , P=0.01 ; 10 % , P=0.02 ; and 27 % , P=0.03 respectively for continuous training and by 21 % , P≤0.05 ; 8 % , P=0.01 ; 6 % , P = NS ; and 48 % , P=0.02 respectively for interval training ) . However , only patients exercised under the continuous training regime had a significant increase in HRR1 ( 15.0±9.0 to 24.0±12bpm ; P=0.02 ) and CR ( 57±19 to 72±21 % , P=0.02 ) , in contrast with those assigned to interval training ( HRR1 : 21 ± 11 to 21 ± 8 bpm ; P = NS and CR : 57 ± 18 to 59 ± 21 % , P = NS ) . Conclusions Both continuous and interval exercise training program improves exercise capacity  in CHF patients . However , continuous rather than interval exercise training improves early HRR1 , a marker of parasympathetic activity , suggesting a greater contribution to the autonomic nervous system Introduction Physical fitness is an important prognostic factor in heart failure ( HF ) . To improve fitness , different types of exercise have been explored , with recent focus on high-intensity interval training ( HIT ) . We comprehensively compared effects of HIT versus continuous training ( CT ) in HF patients NYHA II-III on physical fitness , cardiovascular function and structure , and quality of life , and hypothesize that HIT leads to superior improvements compared to CT . Methods Twenty HF patients ( male : female 19:1 , 64±8 yrs , ejection fraction 38±6 % ) were allocated to 12-weeks of HIT ( 10 * 1-minute at 90 % maximal workload — alternated by 2.5 minutes at 30 % maximal workload ) or CT ( 30 minutes at 60–75 % of maximal workload ) . Before and after intervention , we examined physical fitness ( incremental cycling test ) , cardiac function and structure ( echocardiography ) , vascular function and structure ( ultrasound ) and quality of life ( SF-36 , Minnesota living with HF question naire ( MLHFQ ) ) . Results Training improved maximal workload , peak oxygen uptake ( VO2peak ) related to the predicted VO2peak , oxygen uptake at the anaerobic threshold , and maximal oxygen pulse ( all P<0.05 ) , whilst no differences were present between HIT and CT ( N.S. ) . We found no major changes in resting cardiovascular function and structure . SF-36 physical function score improved after training ( P<0.05 ) , whilst SF-36 total score and MLHFQ did not change after training ( N.S. ) . Conclusion Training induced significant improvements in parameters of physical fitness , although no evidence for superiority of HIT over CT was demonstrated . No major effect of training was found on cardiovascular structure and function or quality of life in HF patients NYHA II-III . Trial Registration Nederl and s Trial Register BACKGROUND Peak oxygen uptake ( Vo(2peak ) ) strongly predicts mortality in cardiac patients . We compared the effects of aerobic interval training ( AIT ) versus moderate continuous training ( MCT ) on Vo(2peak ) and quality of life after  coronary artery bypass grafting ( CABG ) . METHODS Fifty-nine CABG patients were r and omized to either AIT at 90 % of maximum heart rate or MCT at 70 % of maximum heart rate , 5 d/wk , for 4 weeks at a rehabilitation center . Primary outcome was Vo(2peak ) , at baseline , after rehabilitation ( 4 weeks ) , and after 6 months of home-based exercise ( 6 months ) . RESULTS Vo(2peak ) increased between baseline and 4 weeks in AIT ( 27.1 + /- 4.5 vs 30.4 + /- 5.5 mL.kg(-1).min(-1 ) , P < .001 ) and MCT ( 26.2 + /- 5.2 vs 28.5 + /- 5.6 mL.kg(-1).min(-1 ) , P < .001 ; group difference , not significant ) . Aerobic interval training increased Vo(2peak ) between 4 weeks and 6 months ( 30.4 + /- 5.5 vs 32.2 + /- 7.0 mL.kg(-1).min(-1 ) , P < .001 ) , with no significant change in MCT ( 28.5 + /- 5.6 vs 29.5 + /- 5.7 mL.kg(-1).min(-1 ) ) . Quality of life improved in both groups from baseline to 4 weeks , remaining improved at 6 months . There were no changes in echocardiographic systolic and diastolic left ventricular function . Adiponectin increased between 4 weeks and 6 months in both groups ( group differences , not significant ) . CONCLUSIONS Four weeks of intense training increased Vo(2peak ) significantly after both AIT and MCT . Six months later , the AIT group had a significantly higher Vo(2peak ) than MCT . The results indicate that AIT and MCT increase Vo(2peak ) similarly in the short term , but with better long-term effect of AIT after CABG We found that interval training provides an effective means to improve the cardiovascular fitness and health status of highly functional patients with coronary artery disease . We also revealed that interval training improves anaerobic tolerance to a greater extent than the traditional exercise training model without increasing the risk to the patient . This research supports the implementation of interval training for highly functional patients with coronary artery disease Background High-intensity interval training ( HIT ) as exercise therapy is gradually implemented in cardiac rehabilitation as the cardiovascular benefits from exercise is intensity dependent . However , in previous studies , HIT has been performed with strict supervision . The aim of the study was to assess the feasibility and effectiveness of different modes of HIT in cardiac rehabilitation . Design a r and omized clinical study . Methods Ninety participants with coronary artery disease ( 80 men/10 women , mean age 57 ± 8 years ) were r and omly assigned to one of three exercise modes : group exercise ( GE ) , treadmill exercise ( TE ) , or home-based exercise ( HE ) . HIT was performed twice a week for 12 weeks with an exercise intensity of 85–95 % of peak heart rate . The primary outcome measure was change in peak oxygen uptake ( peak VO2 ) . Results Eighty-three participants ( 92 % ) completed the intervention without any severe adverse events . Peak VO2 increased from 34.7 ± 7.3 to 39.0 ± 8.0 ml/kg/min , 32.7 ± 6.5 to 36.0 ± 6.2 ml/kg/min , and 34.4 ± 4.8 to 37.2 ± 5.2 ml/kg/min in TE , GE , and HE , respectively . Mean group difference for TE vs. HE was 1.6 ml/kg/min ( 95 % confidence interval , CI , 0.7 to 3.1 , p = 0.02 ) , TE vs. GE 1.1 ml/kg/min ( 95 % CI−0.5 to 2.5 , p = 0.27 ) , and GE vs. HE 0.6 ml/kg/min ( 95 % CI −1.0 to 2.1 , p = 1 ) . However , on-treatment analysis showed no significant difference between groups . Conclusion HIT was efficiently performed in three setting s of cardiac rehabilitation , with respect to target exercise intensity , exercise attendance , and increase in peak VO2 . Exercise mode was not essential for exercise capacity Abstract Background : High-intensity interval training ( HIIT ) has been shown to improve cardiometabolic health during supervised lab-based studies but adherence , enjoyment , and health benefits of HIIT performed independently are yet to be understood . We compared adherence , enjoyment , and cardiometabolic outcomes after 8 weeks of H 
    Output:
    
Conclusions HIIT has shown a relatively low rate of major adverse cardiovascular events for patients with coronary artery disease or heart failure when applied within CR setting