Optimizing Training Response for Women in Cardiac Rehabilitation

Abstract

eak aerobic exercise capacity, measured as peak oxygen uptake (peak VO 2 ), is a powerful predictor of mortality among cardiac patients. 1 Despite having lower fitness at baseline, women generally do not improve peak VO 2 as much as men in phase 2 cardiac rehabilitation (CR). 2,3 In a prior study of 1789 patients performing standard CR training, women improved by a mean (SD) 0.3 (0.4) L/min and men improved by a mean (SD) 0.4 (0.5) L/min (14% vs 19%, respectively). 3 High-intensity interval training (HIIT) has been shown to be more effective in increasing peak VO 2 compared with moderate intensity continuous training (MCT). However, benefits with HIIT for women are unclear because most studies of HIIT have included primarily men. 4,5 Additionally, resistance training (RT) alone has been shown to improve leg strength and walking endurance in older individuals. 6 The purpose of this study is to examine the combination of HIIT and more intensive RT to maximize peak VO 2 for women in CR. We hypothesized that increases in peak VO 2 (L/min) would be greater among women performing HIIT and additional leg strength training compared with standard MCT. MethodsThis was a randomized clinical study performed from July 2017 to February 2020 and approved by the University of Vermont Institutional Review Board. A detailed protocol is available in Supplement 1. Written informed consent was obtained by all participants.Women entering CR at a community-based cardiac rehabilitation program affiliated with a university hospital in IMPORTANCE Despite lower baseline fitness levels, women in cardiac rehabilitation (CR) do not typically improve peak aerobic exercise capacity (defined as peak oxygen uptake [peak VO 2 ]) compared with men in CR. OBJECTIVE To evaluate the effect of high-intensity interval training (HIIT) and intensive lower extremity resistance training (RT) compared with standard moderate intensity continuous training (MCT) on peak VO 2 among women in CR. DESIGN, SETTING, AND PARTICIPANTS This randomized clinical trial conducted from July 2017 to February 2020 included women from a community-based cardiac rehabilitation program affiliated with a university hospital in Vermont. A total of 56 women (mean [SD] age, 65 [11] years; range 43-98 years) participating in CR enrolled in the study.INTERVENTIONS MCT (70% to 85% of peak heart rate [HR]) with moderate intensive RT or HIIT (90% to 95% of peak HR) along with higher-intensity lower extremity RT 3 times per week over 12 weeks. MAIN OUTCOMES AND MEASURESThe primary outcome was the between-group difference in change in peak VO 2 (L/min) from baseline to 12 weeks. RESULTSPeak VO 2 increased to a greater degree in the HIIT group (+23%) than in the control group (+7%) (mean [SD] increase, 0.3 [0.2] L/min vs 0.1 [0.2] L/min; P = .03). Similarly, the change in leg strength was greater in the HIIT-RT group compared with the control group (mean [SD] increase, 15.3 [0.3] kg vs 6.4 [1.1] kg; P = .004). CONCLUSIONS AND RELEVANCEAn exercise protocol combining HIIT and intensive lower ex...

High-Intensity Interval Training vs Moderate-Intensity Continuous Training for Women Undergoing Cardiovascular Rehabilitation

“…Primary support given for this conclusion centered on the larger change in peak V o 2 for HIIT (n = 22) vs MCT (n = 21) participants (mean [SD] peak V o 2 : HIIT, 0.3 [0.2] L/min; MCT, 0.1 [0.2] L/min; P = .03). However, peak V o 2 changes were not significantly different between groups when analyzed in typical units of mean (SD) mL/kg/min, consistent with peak V o 2 increasing within both HIIT (entry, 18.8 [3.7] mL/kg/min; exit, 22.6 [4.7] mL/kg/min; P < .001) and MCT (entry, 19.3 [4.8] mL/kg/min; exit, 21.9 [5.9] mL/kg/min; P < .001) . This similarity is noteworthy given the powerful prognostic value associated with peak V o 2 in mL/kg/min, as noted in background evidence cited by the authors, which we also agree with .…”

“…To the Editor In a recent article by Khadanga et al, it is reported that among women participating in phase 2 cardiac rehabilitation, undergoing an exercise intervention involving high-intensity interval training (HIIT) and intensive lower extremity resistance training (RT) yields significantly larger increases in peak exercise oxygen uptake (peak V o 2 ) compared with changes resulting from moderate-intensity continuous training (MCT) and low-intensity RT. Primary support given for this conclusion centered on the larger change in peak V o 2 for HIIT (n = 22) vs MCT (n = 21) participants (mean [SD] peak V o 2 : HIIT, 0.3 [0.2] L/min; MCT, 0.1 [0.2] L/min; P = .03).…”

High-Intensity Interval Training vs Moderate-Intensity Continuous Training for Women Receiving Cardiovascular Rehabilitation—Reply

“…In Reply We appreciate the thoughtful commentary from Terada et al and Van Iterson et al to our article . In our study, the moderate continuous training (MCT) group achieved a modest yet significant weight loss, while the high-intensity interval training (HIIT) group remained weight stable.…”

Supplementation with okra combined or not with exercise training is able to protect the heart of animals with metabolic syndrome

“…In addition to ET being a low-cost approach, its effectiveness for disease prevention 11 and treatment 12,13 is well established in the literature. According to Ruberti et al, moderate-intensity aerobic ET is capable of promoting reduction of cardiometabolic alterations in cardiac tissue, reduction of collagen fraction after infarction and maintaining lower blood pressure levels compared to the sedentary group, although this difference is not statistically significant 14 .…”