***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: The oxygen uptake efficiency slope ( OUES ) is a submaximal index incorporating cardiovascular , peripheral , and pulmonary factors that determine the ventilatory response to exercise . The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease . Thirty-five patients ( 59.3±1.8 years old ; 28 men , 7 women ) with coronary artery disease were r and omly divided into two groups : continuous exercise training ( n=18 ) and interval exercise training ( n=17 ) . All patients performed grade d exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold ( VAT ) , respiratory compensation point , and peak oxygen consumption ( peak VO2 ) . The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation . After the interventions , both groups showed increased aerobic fitness ( P<0.05 ) . In addition , both the continuous exercise and interval exercise training groups demonstrated an increase in OUES ( P<0.05 ) . Significant associations were observed in both groups : 1 ) continuous exercise training  ( OUES and peak VO2 r=0.57 ; OUES and VO2 VAT r=0.57 ) ; 2 ) interval exercise training ( OUES and peak VO2 r=0.80 ; OUES and VO2 VAT r=0.67 ) . Continuous and interval exercise training result ed in a similar increase in OUES among patients with coronary artery disease . These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms Objective . To study the effect of aerobic treadmill exercise training with different intensity on left ventricular ( LV ) function in patients with stable coronary artery disease , using Strain Rate- and Tissue Doppler Imaging . Design . Seventeen patients were r and omly assigned to either moderate ( 50–60 % of peak oxygen uptake ( VO2peak ) ) or high intensity exercise ( 80–90 % of VO2peak ) for 10 weeks . Results . The increase of VO2peak was significantly higher ( p=0.01 ) in the high intensity group ( 17 vs. 8 % ) . Mean LV early diastolic strain rate increased in the high , but not in the moderate , intensity group . For systolic strain rate or mitral annular velocities there were no change after training in either group . Conclusions . Aerobic treadmill exercise improves early diastolic relaxation in patients with stable coronary artery disease , measured by the mean LV early diastolic strain rate 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 Peak oxygen uptake ( pVO2 ) is used for risk stratification in chronic heart failure ( CHF ) , but little is known about the prognostic impact of pVO2-changes in patients on chronic beta-blocker ( BBL ) therapy .  We therefore prospect ively evaluated individual pVO2-changes at a 6-month interval in patients all receiving BBL . METHODS 194 patients with stable CHF on stable medication were included ( V1 ) and underwent clinical evaluation and exercise testing . Testing was repeated ( V2 ) at 5.7+/-1.5 months after V1 and patients were followed > 12 months after V2 . Death or hospitalisation due to cardiac reasons was the predefined EP ( EPP , end-point positive ; n=62 ; EPN , end-point negative ; n=113 ) . RESULTS Initial characteristics did not differ between EPP and EPN . Multivariate cox regression analysis revealed that change of pVO2 ( EPP : -0.6+/-2.6 ml/kg min ; EPN : + 2.5+/-3.3 ml/kg min ; p<0.001 ) was independent to pVO2 , LVEF , NTproBNP and NYHA at V2 for prediction of the combined end-point during follow-up . An increase of pVO2 by 10 % was identified as an adequate cut-off value for risk stratification and ROC- analysis showed the significant incremental prognostic value of the determination of pVO2 changes in combination with pVO2 . CONCLUSIONS Serial measurements of pVO2 yield additional information for risk stratification in clinical ly homogenous CHF patients receiving  BBL . This is the first study demonstrating this fact within a narrow predefined interval with all patients on BBL The aim of the present study was to investigate effects of aerobic interval training ( AIT ) versus moderate continuous training ( MCT ) on coronary atherosclerosis in patients with significant coronary artery disease on optimal medical treatment . Thirty-six patients were r and omized to AIT ( intervals at ≈ 90 % of peak heart rate ) or MCT ( continuous exercise at ≈ 70 % of peak heart rate ) 3 times a week for 12 weeks after intracoronary stent implantation . Grayscale and radiofrequency intravascular ultrasounds ( IVUS ) were performed at baseline and follow-up . The primary end point was the change in plaque burden , and the secondary end points were change in necrotic core and plaque vulnerability . Separate lesions were classified using radiofrequency IVUS criteria . We demonstrated that necrotic core was reduced in both groups in defined coronary segments ( AIT -3.2 % , MCT -2.7 % , p < 0.05 ) and in separate lesions ( median change -2.3 % and -0.15 mm(3 ) , p < 0.05 ) . Plaque burden was reduced by 10.7 % in separate lesions independent of intervention group ( p = 0.06 ) . No significant differences in IVUS parameters were found between exercise groups . A minority of separate lesions were transformed in terms of plaque vulnerability during follow-up with large individual differences between and within patients . In conclusion , changes in coronary artery plaque structure or morphology did not differ between patients who underwent AIT or MCT . The combination of regular aerobic exercise and optimal medical treatment for 12 weeks induced a moderate regression of necrotic core and plaque burden in IVUS-defined coronary lesions OBJECTIVE : The purpose of this study was to evaluate the following : 1 ) the effects of continuous exercise training and interval exercise training on the end-tidal carbon dioxide pressure ( PETCO2 ) response during a grade d exercise test in patients with coronary artery disease ; and 2 ) the effects of exercise training modalities on the association between PETCO2 at the ventilatory anaerobic threshold ( VAT ) and indicators of ventilatory efficiency and cardiorespiratory fitness in patients with coronary artery disease . METHODS : Thirty-seven patients ( 59.7±1.7 years ) with coronary artery disease were r and omly divided into two groups : continuous exercise training ( n = 20 ) and interval exercise training ( n = 17 ) . All patients performed a grade d exercise test with respiratory gas analysis before and after three months of the exercise training program to determine the VAT , respiratory compensation point ( RCP ) and peak oxygen consumption . RESULTS : After the interventions , both groups exhibited increased cardiorespiratory fitness . Indeed , the continuous exercise and interval exercise training groups demonstrated increases in both ventilatory efficiency and PETCO2 values at VAT , RCP , and peak of exercise . Significant associations were observed in both groups : 1 ) continuous exercise training ( PETCO2VAT and cardiorespiratory fitness r = 0.49 ; PETCO2VAT and ventilatory efficiency r = -0.80 ) and 2 ) interval exercise training ( PETCO2VAT and cardiorespiratory fitness r = 0.39 ; PETCO2VAT and ventilatory efficiency r = -0.45 ) . CONCLUSIONS : Both exercise training modalities showed similar increases in PETCO2 levels during a grade d exercise test in patients with coronary artery disease , which may be associated with an improvement in ventilatory efficiency and cardiorespiratory fitness 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 Objective : Exercise capacity strongly predicts survival and aerobic interval training ( AIT ) increases peak oxygen uptake effectively in cardiac patients . Usual care in Norway provides exercise training at the hospitals following myocardial infa rct ion ( MI ) , but the effect and actual intensity of these rehabilitation programmes are unknown . Design : R and omized controlled trial . Setting : Hospital cardiac rehabilitation . Subjects : One hundred and seven patients , recruited two to 12 weeks after MI , were r and omized to usual care rehabilitation or treadmill AIT .  Interventions : Usual care aerobic group exercise training or treadmill AIT as 4 × 4 minutes intervals at 85–95 % of peak heart rate . Twice weekly exercise training for 12 weeks . Main measures : The primary outcome measure was peak oxygen uptake . Secondary outcome measures were endothelial function , blood markers of cardiovascular disease , quality of life , resting heart rate , and heart rate recovery . Results : Eighty-nine patients ( 74 men , 15 women , 57.4 ± 9.5 years ) completed the programme . Peak oxygen uptake increased more ( P = 0.002 ) after AIT ( from 31.6 ± 5.8 to 36.2 ± 8.6 mL·kg−1·min−1 , P < 0.001 ) than after usual care rehabilitation ( from 32.2 ± 6.7 to 34.7 ± 7.9 mL·kg−1·min−1 , P < 0.001 ) . The AIT group exercised with significantly higher intensity in the intervals compared to the highest intensity in the usual care group ( 87.3 ± 3. 
    Output:
    
Conclusions High-intensity interval training may improve peak oxygen uptake and should be considered as a component of care of coronary artery disease patients .
However , this superiority disappeared when isocaloric protocol is compared