Effects of interval training in cardiovascular disease populations: a clinical perspective.

Nearly 20 years have elapsed since the first clinical trial investigated the impact of interval training on patients with cardiovascular disease (CVD). This clinical corner discusses the health outcomes of systematic reviews and meta-analyses and appropriately powered randomized clinical trials which have tested these interval training programs across various CVDs (i.e., coronary artery disease, heart failure, atrial fibrillation, peripheral arterial disease, and cardiac implantable electronic devices). The publications included in this clinical corner have shown that interval training leads to similar or superior improvements in peak oxygen uptake (V̇O2peak), functional capacity, pain free walking, quality of life, anxiety, depression, and endothelial function, but the magnitude of improvements across varying protocols (e.g., length and number of work periods, intensities of work periods, duration of exercise sessions, frequency of exercise sessions, and duration of program) and optimal dosage for males and females are unclear across CVD conditions. The heterogeneity in protocols, physical and mental health outcome measures, and lack of sex- and gender-based analyses calls for more high-quality research in this area.

Sex Differences in Physical Activity Levels and Sitting Time in Patients With Atrial Fibrillation.

PURPOSE: While research demonstrates low levels of physical activity (PA) among adults living with atrial fibrillation (AF), there is limited evidence investigating sex differences in moderate to vigorous intensity physical activity (MVPA) and sedentary time in this population. The primary aim was to examine sex differences in MVPA levels and sitting time between women and men with AF. Secondary aims explored sex differences in sociodemographic factors, outcome expectations, and task self-efficacy toward PA levels. METHODS: This was a subanalysis of the CHAMPLAIN-AF cohort study. Women and men with AF completed a survey, including the Short-Form International Physical Activity Questionnaire. RESULTS: A total of 210 women (median = 66.0 yr: 95% CI, 63.5-68.0) and 409 men (median = 66.0 yr: 95% CI, 64.0-67.0) were included. No sex differences were observed in median weekly MVPA (60 min/wk: 95% CI, 0-120 in women vs 120 min/wk: 95% CI, 85-150 in men) and daily sitting time (5.5 hr/d: 95% CI, 5.0-6.0 in women vs 6.0 hr/d: 95% CI, 5.0-6.0 in men). Women engaged in significantly less vigorous-intensity PA than men ( P = .03) and demonstrated significantly lower task self-efficacy ( P < .01). Significant positive correlations in PA levels with outcome expectations (mostly weak) and task self-efficacy (mostly strong) were observed in both sexes. CONCLUSION: Most women and men with AF did not meet the global MVPA guidelines but met the sitting time recommendation. Women presented with lower vigorous-intensity physical activity levels and confidence than men. Strategies to increase physical activity behavior, considering sociodemographic factors and task self-efficacy, are needed and may differ between sexes.

Gamification as a Tool for Promoting Physical Exercise and Healthy Eating Habits in Healthcare Worker Women: Effects on Cardiometabolic Health and Physical Fitness at Workplace.

PURPOSE: To evaluate the effectiveness of gamified versus nongamified health promotion interventions on cardiometabolic health and fitness parameters in healthcare worker women. DESIGN: Randomized parallel group trial. SETTING: A public outpatient health center in Brazil. SUBJECTS: Women employees (included: n = 29; lost to follow-up: n = 1; analyzed: n = 28). INTERVENTIONS: 8 weeks of gamified (n = 15) or nongamified (n = 13) interventions, consisting of health lectures, nutritional counseling, and supervised exercise training. The gamified group was divided into teams that received points based on completion of health goals/tasks. MEASURES: Anthropometric, cardiometabolic and physical fitness parameters. ANALYSIS: Two-way ANOVA with repeated measures (group vs. time), and Bonferroni post hoc tests. RESULTS: Body mass (-1.5 ± 1.5 kg), waist circumference (-1.6 ± 3.0 cm), HbA1C (-.2 ± .3%), triglycerides (-21.5 ± 48.2 mg/dl), systolic (-11.1 ± 7.9 mmHg) and diastolic (-7.1 ± 5.8 mmHg) blood pressure, as well as sit and reach (3.9 ± 3.0 cm) and six-minute walking (56 ± 37 m) performance improved (P < .05) only after the gamified intervention. Sit-to-stand performance improved after both the gamified (-1.18 ± 1.24 s) and nongamified (-1.49 ± 1.87 s) interventions. CONCLUSION: The gamified intervention was more effective than the nongamified intervention for improving cardiometabolic and physical fitness parameters, suggesting that gamification may be an effective tool for promoting health in healthcare worker women.

Sex Differences in Changes in Cardiorespiratory Fitness and Additional Health Outcomes Following Exercise Training in Adults With Atrial Fibrillation: A Systematic Review and Meta-Analysis.

PURPOSE: Improving cardiorespiratory fitness (CRF) through exercise training is associated with lower morbidity and mortality in patients with atrial fibrillation (AF). Smaller CRF improvements have been suggested in females than males with cardiovascular disease following exercise training. This systematic review compared changes in CRF (primary) and additional physical and mental health outcomes following exercise training between females and males with AF. REVIEW METHODS: Five bibliographic databases were searched to identify prospective studies implementing exercise training in patients with AF. The mean difference (MD) in the change following exercise training was compared between sexes using random-effects meta-analyses. SUMMARY: Sex-specific data were obtained from 19 of 63 eligible studies, with 886 participants enrolled in exercise training (n = 259 [29%] females; female: 68 ± 7 years, male: 66 ± 8 years). Exercise training was 6 weeks to 1 year in duration and mostly combined moderate- to vigorous-intensity aerobic and resistance training, 2 to 6 d/wk. Changes in CRF did not differ between sexes (MD = 0.15: 95% CI, -1.08 to 1.38 mL O2/kg/min; P = .81; I2 = 27%). Severity of AF (MD = 1.00: 95% CI, 0.13-1.87 points; I2 = 0%), general health perceptions (MD = -3.71: 95% CI, -6.88 to -0.55 points; I2 = 22%), and systolic blood pressure (MD = 3.11: 95% CI, 0.14-6.09 mmHg; I2 = 42%) improved less in females than in males. Females may benefit from more targeted exercise training programs given their smaller improvement in several health outcomes than males. However, our findings are largely hypothesis-generating, considering the limited sample size and underrepresentation of females (29% females in our review vs 47% females with AF globally).

Effects of exercise training on heart rate variability in individuals with lower extremity arterial disease and claudication: A systematic review.

PURPOSE: To perform a systematic review of studies assessing the effects of regular exercise on heart rate variability (HRV) in individuals with lower extremity arterial disease (LEAD) and symptoms of claudication. METHODS: A systematic search in the electronic databases MEDLINE, Embase, and Scielo, was conducted and updated on January 21, 2023. Randomized clinical trials investigating patients with LEAD and IC, assessing ≥ 4 wk of exercise interventions, and reporting at least one HRV measure (e.g., time or frequency domains) at baseline and follow-up were included. Two reviewers independently screened studies for inclusion, performed data extraction, and quality assessment of included studies. RESULTS: Data from 7 trials were included (i.e., 5 walking, 1 resistance, and 1 isometric handgrip training), totaling 327 patients (66% males; range: 61 - 68 yr; ankle brachial index: 0.4 - 0.7). Following exercise training, three studies investigating walking training reported an increase in parasympathetic modulation indices and/or a decrease in sympathetic modulation indices (n = 2) as well as an increase in non-linear indices (n = 1). CONCLUSION: The current evidence is weak, and larger randomized controlled trials are needed to confirm the efficacy of exercise training in improving HRV. Additionally, the high divergence in the methodology of studies indicated the need for standard tools to improve the quality of HRV measurements in exercise trials. It is recommended to use standard procedures in future trials investigating HRV.

A case series of acute responses to high-intensity interval training in four males with permanent atrial fibrillation.

Background: Atrial fibrillation (AF) is a serious medical condition and a burgeoning patient population. Chronic exercise training, including high-intensity interval training (HIIT), has been shown to improve symptoms and quality of life in patients with AF. Yet, the acute responses to HIIT in this population remain understudied, leaving clinicians and patients hesitant about prescribing and engaging in high-intensity exercise, respectively. Case summary: This case series describes acute exercise responses [i.e. power output, heart rate (HR), blood pressure (BP), ratings of perceived exertion (RPE), symptoms] to 10 weeks (3 days/week) of HIIT. Participants were four white males (58-80 years old) with permanent AF, co-morbidities (diabetes, coronary artery disease, Parkinson's disease), and physical limitations. The increases in HR and BP during HIIT were modest across all participants, regardless of age and medication use. Differences in RPE were observed; the oldest participant perceived the sessions as more challenging despite a lower HR response. All patients complied with the HIIT prescription of 80-100% of peak power output by week 4. No adverse events were reported. Discussion: Patients' concerns regarding high-intensity exercise may discourage them from participating in HIIT, our results demonstrated no abnormal HR or BP (e.g. hypotension) responses during HIIT or cool-down. These findings align with the typical exercise responses noted in other cardiovascular populations. Notwithstanding the high metabolic demands of HIIT, male patients with permanent AF tolerated HIIT without problem. Further investigation of HIIT as an approach to enable those with AF to recover physical capacity and minimize symptomatology is warranted.

Hemodynamic response to exercise is impaired in individuals with Parkinson's disease.

BACKGROUND: The aim of this study was to assess hemodynamic and cardiac autonomic response to high-intensity interval exercise (HIIE) versus moderate-intensity continuous exercise (MICE) in individuals with Parkinson's disease (PD). METHODS: Twelve individuals (six men) with PD were randomly assigned to perform HIIE (4 min of warm-up followed by 21 min alternating 1 min at levels 15-17 with 2 min at levels 9-11 of rating of perceived exertion [RPE] in a cycle ergometer), MICE (4 min of warm-up followed by 26 min at levels 11-14 of RPE in a cycle ergometer) and control (CON; 30 min of sitting rest) interventions in separate days. Heart rate (HR), blood pressure (BP), endothelial reactivity and heart rate variability (HRV) were assessed before, immediately after and 45 min after each intervention. HR and exercise workload were measured during each intervention. RESULTS: Despite the within (high- vs. low-intensity intervals of HIIE) and between (HIIE vs. MICE) differences in workload during exercise sessions, HR was not different between high- (average HR=98±18 bpm) and low-intensity (average HR 97±19 bpm) intervals of HIIE, as well as between HIIE (average HR=97±18 bpm) and MICE (average HR=93±19 bpm) throughout the exercise. There were significant, but small, increases (P<0.01) in HR and systolic BP at post HIIE and MICE, which returned to levels similar to preintervention during recovery. There were no within- and between-intervention differences in diastolic BP, endothelial reactivity and HRV. CONCLUSIONS: The present results suggest that hemodynamic response to exercise is impaired in individuals with PD.

Hemodynamic response to heated water immersion in older individuals with hypertension.

The aim of this study was to evaluate blood pressure (BP), heart rate, arterial stiffness and endothelial reactivity responses to heated water immersion in older individuals with hypertension. Thirty-five sedentary individuals (67 ± 5 years) under treatment for hypertension were randomly assigned to water-based [n = 20; 30 min of seated resting in a heated swimming pool (30-32 °C)] or land-based group [n = 15; 30 min of seated resting in a quiet room with controlled temperature (21-23 °C)]. BP, heart rate, arterial stiffness and endothelial reactivity were measured before, immediately after (post) and 45 min after (recovery) each session. Heart rate reduced (P < 0.05) during the land-based session, and the reduction was maintained at post (~7 bpm) and recovery (~9 bpm), but no heart rate changes occurred during and after the water-based session. Systolic/diastolic BP increased (P = <0.001) at post (~29/10 mmHg) and recovery (~10/7 mmHg) in the water-based group, but not in the land-based group. No significant changes in pulse wave velocity and endothelial reactivity occurred in both groups. These results suggest that the hemodynamic response to heated water immersion should be taken into account when assessing the effect of heated water-based exercise on postexercise hypotension in older individuals with hypertension.

Prescribing high-intensity interval exercise by rating of perceived exertion in young individuals.

BACKGROUND: We tested the hypothesis that the 6 to 20 rating of perceived exertion (RPE) is a cost-effective tool similar to heart rate (HR) response to cardiopulmonary exercise test for prescribing and self-regulating high-intensity interval exercise (HIIE). In this context, we analyzed if health-related responses to exercise are similar between HIIE prescribed and self-regulated by RPE (HIIERPE) and HIIE prescribed and regulated by HR response to cardiopulmonary exercise test (HIIEHR). METHODS: Twelve young (21±2 years) sedentary or insufficiently active individuals (weekly levels ˂150 minutes or 75 minutes of moderate- or vigorous-intensity physical activity, respectively) were randomly assigned to perform HIIERPE (25 minutes), HIIEHR (25 minutes) and control session (25 minutes of seated resting). Blood pressure, HR, and arterial stiffness (pulse wave velocity) were measured before, immediately after, and 30 minutes after each intervention. HR, speed, and distance were measured during exercise sessions. 24-hours ambulatory blood pressure was measured after each intervention. RESULTS: Exercise HR, speed, and distance, as well as blood pressure response to exercise were not different between HIIERPE and HIIEHR. Pulse wave velocity reduced (P<0.05) at postintervention in both HIIERPE (0.28±0.17 m/s) and HIIEHR (0.27±0.11 m/s). However, pulse wave velocity at recovery was lower than pre-intervention only during HIIERPE (0.30±0.10 m/s). CONCLUSIONS: These results suggest that RPE is a cost-effective tool for prescribing self-regulating HIIE and improving health-related variables in young individuals.

Cardiac reinnervation affects cardiorespiratory adaptations to exercise training in individuals with heart transplantation.

PURPOSE: The purpose of this study was to investigate the hemodynamic and cardiorespiratory adaptations to exercise in individuals with heart transplantation with evidence of cardiac reinnervation (cardiac reinnervation group) versus without evidence of cardiac reinnervation (no cardiac reinnervation group). METHODS: Sedentary individuals with heart transplantation (age = 45.5 ± 2.2 years; time elapsed since surgery = 6.7 ± 0.7 years) were divided into the cardiac reinnervation (n = 16) and no cardiac reinnervation (n = 17) groups according to their heart rate response to cardiopulmonary exercise testing. The 24-hour ambulatory blood pressure, carotid-femoral pulse wave velocity, and cardiorespiratory fitness were assessed before and after 12 weeks of a thrice-weekly exercise program (five minutes of warm-up, 30 min of endurance exercise, one set of 10-15 reps in five resistance exercises, and five minutes of cool-down). RESULTS: The cardiac reinnervation group had reduced (p < 0.01) 24-hour systolic/diastolic blood pressure (7/9 mm Hg), daytime systolic/diastolic blood pressure (9/10 mm Hg) and nighttime diastolic blood pressure (6 mm Hg) after training. The no cardiac reinnervation group reduced (p < 0.05) only 24-hour (5 mm Hg), daytime (5 mm Hg) and nighttime (6 mm Hg) diastolic blood pressure after training. Hourly analysis showed that the cardiac reinnervation group reduced systolic/diastolic blood pressure for 10/21 h, while the no cardiac reinnervation group reduced systolic/diastolic blood pressure for only 3/11 h. The cardiac reinnervation group also improved both maximal oxygen consumption (10.8%) and exercise tolerance (13.4%) after training, but the no cardiac reinnervation group improved only exercise tolerance (9.9%). Pulse wave velocity did not change in both groups. CONCLUSION: There were greater improvements in ambulatory blood pressure and maximal oxygen consumption in the cardiac reinnervation than the no cardiac reinnervation group. These results suggest that cardiac reinnervation associates with hemodynamic and cardiorespiratory adaptations to exercise training in individuals with heart transplantation.