Jeffrey W. Christle

High-Intensity Interval Training in Patients with Heart Failure with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

High Intensity Interval Training in Heart Failure Patients with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

Accuracy in Wrist-Worn, Sensor-Based Measurements of Heart Rate and Energy Expenditure in a Diverse Cohort

The ability to measure physical activity through wrist-worn devices provides an opportunity for cardiovascular medicine. However, the accuracy of commercial devices is largely unknown. The aim of this work is to assess the accuracy of seven commercially available wrist-worn devices in estimating heart rate (HR) and energy expenditure (EE) and to propose a wearable sensor evaluation framework. We evaluated the Apple Watch, Basis Peak, Fitbit Surge, Microsoft Band, Mio Alpha 2, PulseOn, and Samsung Gear S2. Participants wore devices while being simultaneously assessed with continuous telemetry and indirect calorimetry while sitting, walking, running, and cycling. Sixty volunteers (29 male, 31 female, age 38 ± 11 years) of diverse age, height, weight, skin tone, and fitness level were selected. Error in HR and EE was computed for each subject/device/activity combination. Devices reported the lowest error for cycling and the highest for walking. Device error was higher for males, greater body mass index, darker skin tone, and walking. Six of the devices achieved a median error for HR below 5% during cycling. No device achieved an error in EE below 20 percent. The Apple Watch achieved the lowest overall error in both HR and EE, while the Samsung Gear S2 reported the highest. In conclusion, most wrist-worn devices adequately measure HR in laboratory-based activities, but poorly estimate EE, suggesting caution in the use of EE measurements as part of health improvement programs. We propose reference standards for the validation of consumer health devices (http://precision.stanford.edu/).

The Impact of a Ten-Week Physical Exercise Program on Health-Related Quality of Life in Patients with Inflammatory Bowel Disease: A Prospective Randomized Controlled Trial

Background: Improving health-related quality of life is a primary target of therapy for patients with inflammatory bowel disease. Physical activity has been demonstrated to improve health-related quality of life in several patient populations with chronic disease. There are very few studies investigating the effects of physical activity on health-related quality of life in inflammatory bowel disease. The primary purpose of this study is to investigate the effects of 10 weeks of moderate physical activity on health-related quality of life in patients with inflammatory bowel disease. Methods: Thirty patients with mild to moderate IBD (Crohn‘s Disease Activity Index (CDAI) <220 or Rachmilewitz Index (RI) <11) were randomized 1:1 to either supervised moderate-intensity running thrice a week for 10 weeks or a control group who were not prescribed any exercise. Health-related quality of life, symptoms, and inflammation were assessed at baseline and after 10 weeks. Results: Participants were 41 ± 14 years (73% female), had a body mass index of 22.8 ± 4.1 kg/m2, and an average CDAI or RI of 66.8 ± 42.4 and 3.6 ± 3.1. No adverse events occurred during the 10-week training period. Health-related quality of life, reported as IBDQ total score, improved 19% in the intervention group and 8% in the control group. Scores for the IBDQ social sub-scale were significantly improved in the intervention group compared with controls (ΔIBDQsocial = 6.27 ± 5.46 vs. 1.87 ± 4.76, p = 0.023). Conclusion: Patients suffering from moderately active IBD are capable of performing symptom-free regular endurance exercise. Our data support the assumption that PA is feasible in IBD patients. PA may furthermore improve quality of life through improvements in social well-being, and may, therefore, be a useful adjunct to IBD therapy.

Effects of a physical education program on physical activity, fitness, and health in children: the JuvenTUM project.

The purpose of the study was to investigate the effects of a school‐based prevention program on physical activity, fitness, and obesity. We performed a prospective study in eight Bavarian primary schools (n = 724 children, 8.4 ± 0.7 years) randomized one to one to either an intervention school (IS, n = 427) or a control school (CS, n = 297). Children in IS attended 10 health‐related lessons at school over a period of 1 year. Parents and teachers attended two and three educational health‐related lessons, respectively, and also received 10 newsletters on health issues. Daily physical activity (≥ 60 min/day), physical fitness (six‐item test battery), and anthropometric data were obtained at baseline and after 1 year. Physical activity and physical fitness increased in IS, but it failed to reach significant intervention effects. Nevertheless, a reduction in waist circumference was observed for all children [mean change 1.7 cm; 95% confidence interval (CI) 1.2–2.3; P < 0.001). This effect was more pronounced in overweight children (> 90th percentile, n = 99, mean change 3.2 cm; 95% CI 1.5–4.8; P < 0.001). This easily administered preventative program involving children, parents, and teachers revealed that a generalized approach increasing physical activity will even be favorable in a subgroup of obese children.

Exercise training improves exercise capacity and quality of life after transcatheter aortic valve implantation: A randomized pilot trial

BACKGROUND Transcatheter aortic valve implantation (TAVI) is increasingly applied for aortic stenosis in elderly patients with impaired mobility and reduced quality of life. These patients may particularly benefit from postinterventional exercise programs, but no randomized study has evaluated the safety and efficacy of exercise in this population. METHODS In a prospective pilot study, 30 patients after TAVI (mean age, 81±6 years, 44% female, 83±34 days postintervention) were randomly allocated 1:1 to a training group (TG) performing 8 weeks of supervised combined endurance and resistance exercise or to usual care. The formal primary efficacy end point was between-group difference in change in peak oxygen uptake assessed by cardiopulmonary exercise testing; secondary end points included muscular strength, 6-minute walk distance, and quality of life (Kansas City Cardiomyopathy Questionnaire and Medical Outcomes Study 12-Item Short-Form Health Survey questionnaires). Safety was assessed by documenting training-related adverse events, prosthesis, and renal function. RESULTS Significant changes in favor of TG were observed for peak oxygen uptake (group difference, 3.7 mL/min per kg [95% CI, 1.1-6.3; P=.007]), muscular strength (bench press, 6 kg [95% CI, 3-10; P=.002]; rowing, 7 kg [95% CI, 3-11; P<.001]; pulldown, 9 kg [95% CI, 4-14; P=.001]; shoulder press, 5 kg [95% CI, 1-8; P=.008]; leg press, 17 kg [95% CI 6-28; P=.005]), components of quality of life (Kansas City Cardiomyopathy Questionnaire physical limitation, 19.2 [95% CI, 4.1-34.2; P=.015]; symptom burden, 12.3 [95% CI, 0.5-24.0; P=.041]; clinical summary, 12.4 [3.4-21.4; P=.009]), but not for other questionnaire subscales and 6-minute walk distance (15 m [95% CI, -23 to 53; P=.428]). Three dropouts unrelated to exercise occurred (TG=2; usual care,=1); prosthesis and renal function were not affected by the exercise intervention. CONCLUSIONS In patients after TAVI, exercise training appears safe and highly effective with respect to improvements in exercise capacity, muscular strength, and quality of life. CLINICAL TRIAL REGISTRATION Clinicaltrials.govNCT01935297.

A Reference Equation for Normal Standards for VO2 Max: Analysis from the Fitness Registry and the Importance of Exercise National Database (FRIEND Registry)

Existing normal standards for maximal oxygen uptake (VO2 max) are problematic because they tend to be population specific, lack normal distribution and portability, and are poorly represented by women. The objective of the current study was to apply the Fitness Registry and the Importance of Exercise: A National Data Base (FRIEND) Registry to improve upon previous regression formulas for normal standards for VO2 max using treadmill testing. Maximal treadmill tests were performed in 7783 healthy men and women (20-79years; maximal RER >1.0) from the FRIEND registry and a separate validation cohort of 1287 subjects. A regression equation for VO2 max was derived from the FRIEND registry and compared to the validation cohort and two commonly used equations (Wasserman and European). Age, gender, and body weight were the only significant predictors of VO2 max (multiple R=0.79, R2=0.62, p<0.001). The equation for predicting VO2 max was: [Formula: see text] Marked differences were observed in percentage predicted VO2 max achieved between commonly used reference equations, particularly among women, overweight and obese subjects. In the validation sample, the FRIEND equation closely paralleled measured VO2 max, with the validation group yielding a percent predicted VO2 max of 100.4% based on the FRIEND equation. An equation for age-predicted VO2 max derived from the FRIEND registry provided a lower average error between measured and predicted VO2 max than traditional equations, and thus may provide a more suitable normal standard relative to traditional equations.

Cardiopulmonary response during whole-body vibration training in patients with severe COPD

Several studies in patients with chronic obstructive pulmonary disease (COPD) have shown that whole-body vibration training (WBVT) has beneficial effects on exercise capacity. However, the acute cardiopulmonary demand during WBVT remains unknown and was therefore investigated in this study. Ten patients with severe COPD (forced expiratory volume in 1 s: 38±8% predicted) were examined on two consecutive days. On day one, symptom-limited cardiopulmonary exercise testing was performed on a cycle ergometer. The next day, six bouts of repeated squat exercises were performed in random order for one, two or three minutes either with or without WBVT while metabolic demands were simultaneously measured. Squat exercises with or without WBVT induced comparable ventilatory efficiency (minute ventilation (VE)/carbon dioxide production (V′CO2): 38.0±4.4 with WBVT versus 37.4±4.1 without, p=0.236). Oxygen uptake after 3 min of squat exercises increased from 339±40 mL·min−1 to 1060±160 mL·min−1 with WBVT and 988±124 mL min−1 without WBV (p=0.093). However, there were no significant differences between squat exercises with and without WBVT in oxygen saturation (90±4% versus 90±4%, p=0.068), heart rate (109±13 bpm versus 110±15 bpm, p=0.513) or dyspnoea (Borg scale 5±2 versus 5±2, p=0.279). Combining squat exercises with WBVT induced a similar cardiopulmonary response in patients with severe COPD compared to squat exercises without WBVT. Bearing in mind the small sample size, WBVT might be a feasible and safe exercise modality even in patients with severe COPD. Whole-body vibration training is a feasible and safe exercise modality even in patients with severe COPD http://ow.ly/FNK5307VSPC

Individualized vs. group exercise in improving quality of life and physical activity in patients with cardiac disease and low exercise capacity: results from the DOPPELHERZ trial

Abstract Purpose: Important goals of cardiac rehabilitation maintenance programs (CMP) are to increase leisure time physical activity (LTPA) and improve health-related quality of life (HRQoL). Elderly patients with cardiac disease and low exercise capacity are simultaneously the most severely affected and have the most to gain from exercise-based rehabilitation. Individualized combined exercise (ICE) may be an effective modality to achieve these goals. We compared six months of ICE to CMP in their effects on LTPA and HRQoL. Methods: Sixty patients (70 ± 9 years, 39% female) with cardiac disease and low exercise capacity (<6 MET) were randomly allocated to six months of once-weekly ICE or CMP. The patients in ICE performed moderate endurance and resistance exercise on machines, based on intensities from individual peak exercise testing. Patients in CMP performed weekly sessions of calisthenics, flexibility, coordination and relaxation activities. LTPA and HRQoL were assessed with accelerometry and questionnaires at baseline and six months. Results: Sixty patients completed the trial. ICE increased vigorous PA (ICE: Δ + 12 MET-min/d, CMP: Δ –5 MET-min/d, p = .02) and steps per day (ICE: +1586 steps/d, CMP: –838 steps/d, p < .01) compared to CMP after six months. ICE significantly improved in several components of HRQoL (vitality, emotional health, social health, positive and negative affect (all p < .05) compared to CMP. Conclusions: ICE resulted in significant improvements in physical activity levels and health related quality of life in moderate to high-risk patients compared to CMP. Implications for rehabilitation Relatively low volumes and intensities of exercise may lead to substantial improvements in both physical activity levels and health-related quality of life Exercise modes in cardiac rehabilitation maintenance programs should not be limited to calisthenics and large group-based exercise Supplemental resistance exercise may improve health-related quality of life and increase physical activity levels in patients with low exercise capacity Moderate to high-risk elderly patients also benefit from individualized endurance-resistance exercise

Interval exercise training increases maximal and submaximal exercise performance in heart failure with biventricular assist device therapy.

Heart transplantation is currently the preferred treatment for patients with end stage heart failure, with a median survival rate of 11 years for all patients and 14 years for patients who survive the early post-implantation period [1]. A limited number of donor organs andmorepeople livingwith serious heart failure have increasedtheimportance for alternative options. Ventricular assist devices are being successfully used as bridge-to-transplant or as destination therapy when heart transplantation cannot be considered, for example due to inoperability or non-compliance. Implantation of a VAD has shown to improve exercise capacity, quality of life and mortality in patients with severe heart failure, although exercise capacity after VAD therapy remainsbelow that reportedfor age-matchedcontrolsafter heart transplantation [2]. Exercise and improved peak oxygen uptake (VO2peak) are related to improved quality of life and prognosis in patients with severe heart failure [3]. Therefore, improving VO2 peak is an important goal with multifaceted clinical relevance in patients on VAD therapy. The few studies investigating exercise in patients on VAD therapy