Aerobic interval training compensates age related decline in cardiac function.

OBJECTIVES: To study the effect of aerobic interval training (AIT) on myocardial function in sedentary seniors compared to master athletes (MA) and young controls. DESIGN: Sixteen seniors (72 ± 1 years, 10 men) performed AIT (4 × 4 minutes) at ≈ 90% of maximal heart rate three times per week for 12 weeks. Results were compared with 11 male MA (74 ± 2 years) and 10 young males (23 ± 2 years). RESULTS: Seniors had an impaired diastolic function compared to the young at rest. AIT improved resting diastolic parameters, increased E/A ratio (44%, p <0.01), early diastolic tissue Doppler velocity (e') (11%, p <0.05) and e' during exercise (11%, p <0.01), shortened isovolumic relaxation rate (IVRT) (13%, p <0.01). Left ventricle (LV) systolic function (S') was unaffected at rest, whereas S' during stress echo increased by 29% (p <0.01). Right ventricle (RV) S' and RV fractional area change (RFAC) increased (9%, p <0.01, 12%, p =0.01, respectively), but not RV e'. MA had the highest end-diastolic volume, stroke volume, diastolic reserve and RV S'. CONCLUSION: AIT partly reversed the impaired age related diastolic function in healthy seniors at rest, improved LV diastolic and systolic function during exercise as well as RV S' at rest.

Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study.

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 infarction (MI), but the effect and actual intensity of these rehabilitation programmes are unknown. DESIGN: Randomized controlled trial. SETTING: Hospital cardiac rehabilitation. SUBJECTS: One hundred and seven patients, recruited two to 12 weeks after MI, were randomized 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 ± 3.9% versus 78.7 ± 7.2% of peak heart rate, respectively, P < 0.001). Both programmes increased endothelial function, serum adiponectin, and quality of life, and reduced serum ferritin and resting heart rate. High-density lipoprotein cholesterol increased only after AIT. CONCLUSIONS: AIT increased peak oxygen uptake more than the usual care rehabilitation provided to MI patients by Norwegian hospitals.

Digital interventions to promote physical activity among inactive adults: A study protocol for a hybrid type I effectiveness-implementation randomized controlled trial.

Introduction: Physical inactivity is the fourth leading risk factor for global mortality, and inactive adults have a higher risk to develop lifestyle diseases. To date, there is preliminary evidence of the efficacy of fitness technologies and other digital interventions for physical activity (PA) promotion. Intervention studies are needed to test the effectiveness and implementation of innovative PA promotion strategies. Methods and analysis: The ONWARDS study is a hybrid type I effectiveness-implementation randomized control trial aiming at an inactive and presumably high-risk population living in Northern Norway. One hundred and eighty participants will be assigned to 3 groups in a 1:1:1 ratio and participate for 18 months. Participants in group A will be provided an activity tracker with the personalized metric Personal Activity Intelligence (PAI). Participants in group B will be provided with both an activity tracker with the personalized metric PAI and access to online training videos (Les Mills+) to perform home-based training. Participants in group C will be provided an activity tracker with the personalized metric PAI, home-based online training and additional peer support via social media. The primary objective is to test which combination of interventions is more effective in increasing PA levels and sustaining long-term exercise adherence. Secondary objectives include: proportion of participants reaching PA recommendations; exercise adherence; physical fitness; cardiovascular risk; quality of life; perceived competence for exercise; self-efficacy; social support; usability; users' perspectives on implementation outcomes (adoption, acceptability, adherence, sustainability). The study design will allow testing the effectiveness of the interventions while gathering information on implementation in a real-world situation. Discussion: This study can contribute to reduce disparities in PA levels among inactive adults by promoting PA and long-term adherence. Increased PA might, in turn, result in better prevention of lifestyle diseases. Digital interventions delivered at home can become an alternative to training facilities, making PA accessible and feasible for inactive populations and overcoming known barriers to PA. If effective, such interventions could potentially be offered through national health portals to citizens who do not meet the minimum recommendations on PA or prescribed by general practitioners or specialists. Trial registration: https://clinicaltrials.gov/ct2/show/NCT04526444, Registered 23 April 2021, identifier: NCT04526444.

Onset of exercise training 14 days after uncomplicated myocardial infarction: a randomized controlled trial.

BACKGROUND: Exercise training is an important part of cardiac rehabilitation to reduce morbidity and mortality. Low-intensity exercise training can start as soon as the myocardial infarction (MI) patient is stable. Our objective was to evaluate the effect of an early start of exercise training in MI patients. DESIGN: A randomized controlled trial. METHODS: Thirty-nine MI patients were randomized to either an early start of exercise training group (EG) or to a delayed start control group (CG). The EG participated in an outpatient low-intensity EG (phase 2a) two times a week for 4 weeks before entering ordinary exercise training of moderate-to-high intensity (phase 2b). CG entered phase 2b directly after 4 weeks of delay. Primary outcome measure was peak oxygen consumption (VO2peak), measured at baseline, after 4 weeks and after 16 weeks. Secondary outcome measure was health-related quality of life. RESULTS: VO2peak did not change from baseline to 4 weeks, either in EG [30.6+/-6.7 ml/kg/min vs. 30.7+/-6.2 ml/kg/min, not significant (NS)] or CG (29.8+/-6.1 ml/kg/min vs. 30.7+/-6.2 ml/kg/min, NS). After 16 weeks VO2peak increased in both groups to 33.1+/-7.1 ml/kg/min in EG (P<0.005) and 33.0 ml/kg/min+/-8.6 in CG (P<0.005), group differences NSH. Health-related quality of life increased in every domain but physical functioning for both groups (group differences NS). CONCLUSION: An early start of exercise training did not increase VO2peak compared to 4 weeks of delay. For low-risk patients with high motivation for exercise training, home-based walking is an option as a moderate start of cardiac rehabilitation the first weeks after MI.

Adherence to a Long-Term Physical Activity and Exercise Program After Stroke Applied in a Randomized Controlled Trial.

Background: Persistent physical activity is important to maintain motor function across all stages after stroke. Objective: The objective of this study was to investigate adherence to an 18-month physical activity and exercise program. Design: The design was a prospective, longitudinal study including participants who had had a stroke randomly allocated to the intervention arm of a randomized controlled trial. Methods: The intervention consisted of individualized monthly coaching by a physical therapist who motivated participants to adhere to 30 minutes of daily physical activity and 45 minutes of weekly exercise over an 18-month period. The primary outcome was the combination of participants' self-reported training diaries and adherence, as reported by the physical therapists. Mixed-effect models were used to analyze change in adherence over time. Intensity levels, measured by the Borg scale, were a secondary outcome. Results: In total, 186 informed, consenting participants who had had mild-to-moderate stroke were included 3 months after stroke onset. Mean age was 71.7 years (SD = 11.9). Thirty-four (18.3%) participants withdrew and 9 (4.8%) died during follow-up. Adherence to physical activity and exercise each month ranged from 51.2% to 73.1%, and from 63.5% to 79.7%, respectively. Adherence to physical activity increased by 2.6% per month (odds ratio = 1.026, 95% CI = 1.014-1.037). Most of the exercise was performed at moderate-to-high intensity levels, ranging from scores of 12 to 16 on the Borg scale, with an increase of 0.018 points each month (95% CI = 0.011-0.024). Limitations: Limitations included missing information about adherence for participants with missing data and reasons for dropout. Conclusions: Participants with mild and moderate impairments after stroke who received individualized regular coaching established and maintained moderate-to-good adherence to daily physical activity and weekly exercise over time.

High Intensity Interval Training for Maximizing Health Outcomes.

Regular physical activity and exercise training are important actions to improve cardiorespiratory fitness and maintain health throughout life. There is solid evidence that exercise is an effective preventative strategy against at least 25 medical conditions, including cardiovascular disease, stroke, hypertension, colon and breast cancer, and type 2 diabetes. Traditionally, endurance exercise training (ET) to improve health related outcomes has consisted of low- to moderate ET intensity. However, a growing body of evidence suggests that higher exercise intensities may be superior to moderate intensity for maximizing health outcomes. The primary objective of this review is to discuss how aerobic high-intensity interval training (HIIT) as compared to moderate continuous training may maximize outcomes, and to provide practical advices for successful clinical and home-based HIIT.

Ventilatory efficiency and aerobic capacity in people with multiple sclerosis: A randomized study.

OBJECTIVES: To assess ventilatory efficiency and aerobic capacity in people with multiple sclerosis and whether treadmill walking or progressive strength training has an effect on these parameters in this population. METHODS: In all, 24 adults with multiple sclerosis with an Expanded Disability Status Scale score of ≤6 completed a cardiopulmonary exercise test before and after 8 weeks of exercise. They were randomized to treadmill walking of low-to-moderate intensity (50%-70% of peak heart rate) or progressive strength training (six repetitions × two at 80% of one repetition maximum). Both groups exercised for 30 min three times per week. Primary outcome measure was ventilatory efficiency measured as the minute ventilation/carbon dioxide production (VE/VCO2) ratio and oxygen uptake efficiency slope. Secondary outcome was aerobic capacity, measured as peak oxygen uptake (VO2peak). RESULTS: Despite low aerobic capacity, ventilatory efficiency was found to be within normal range. After 8 weeks of exercise, no significant between-group differences emerged in (1) VE/VCO2 ratio (26 ± 2.2 to 26 ± 2.0, 29 ± 2.0 to 28 ± 2.3, p = 0.66), (2) oxygen uptake efficiency slope (2697 ± 442 to 2701 ± 577, 2473 ± 800 to 2481 ± 896, p = 0.71), or (3) VO2peak in mL/kg/min (28 ± 4.4 to 30 ± 4.3, 29 ± 6.7 to 29 ± 6.4, p = 0.38) in treadmill walking and progressive strength training, respectively. There were no significant within-group differences either. No adverse events occurred during cardiopulmonary exercise test or exercise training. CONCLUSION: In people with mild-to-moderate multiple sclerosis, 8 weeks of treadmill walking of low-to-moderate intensity or progressive strength training did not have any effect on ventilatory efficiency or aerobic capacity. Although aerobic capacity was lower than reference values, ventilatory efficiency was not reduced.

Upper arm venous compliance and fitness in stable coronary artery disease patients and healthy controls.

OBJECTIVES: Arteries have been examined extensively in coronary artery disease (CAD), while less attention has been paid to veins. AIMS: (1) To determine whether venous compliance or venous outflow in the upper arm is reduced in CAD patients compared to healthy age- and fitness-matched controls; and (2) to examine the association between upper arm venous compliance and total blood volume. DESIGN: Fifteen patients with stable CAD (age 62·1 ± 5·7 years, body mass index 26·5 ± 3·2 kg·m2 , fat-free mass 59·3 ± 7·6 kg, mean arterial pressure 98·9 ± 8·0 mmHg, VO2peak : 2·92 ± 0·53 l min-1 ) were compared to twelve healthy age- and fitness-matched controls (age 62·2 ± 3·7 years, body mass index 26·2 ± 2·3 kg m2 , fat-free mass 61·0 ± 9·2 kg, mean arterial pressure 96·5 ± 9·1 mmHg, VO2peak : 3·24 ± 0·48 l min-1 ). Venous compliance was examined using high-resolution ultrasound and Doppler in the basilic vein. Blood volumes were measured by the optimized CO rebreathing method. RESULTS: Equal upper arm venous compliance normalized to blood volume (patients: 0·28 ± 0·26 mm3  mmHg-1  l-1 , healthy controls: 0·16 ± 0·11 mm3 mmHg-1  l-1 ) and peak venous outflow normalized to blood volume (patients: 10·4 ± 3·9 cm s-1  l-1 , healthy controls: 8·3 ± 0·8 cm s-1  l-1 ) were found in patients with CAD and healthy age- and fitness-matched controls. Additionally, no difference was found in blood volume (patients: 6·06 ± 0·79 l, healthy controls: 6·68 ± 1·27 l) or VO2peak . CONCLUSION: Comparable upper arm venous compliance and venous outflow in CAD patients and healthy age- and fitness-matched controls might indicate that high VO2peak and blood volume could prevent possible disease-induced reductions in venous compliance in CAD.

Long-term Exercise Adherence After High-intensity Interval Training in Cardiac Rehabilitation: A Randomized Study.

BACKGROUND AND PURPOSE: Exercise adherence in general is reported to be problematic after cardiac rehabilitation. Additionally, vigorous exercise is associated with impaired exercise adherence. As high-intensity interval training (HIT) is frequently used as a therapy to patients with coronary artery disease in cardiac rehabilitation, the objective was to assess long-term exercise adherence following an HIT cardiac rehabilitation programme. METHODS: A multicentre randomized study was carried out. Eligible participants were adults who had previously attended a 12-week HIT cardiac rehabilitation programme, as either a home-based or hospital-based HIT (treadmill exercise or group exercise). The primary outcome was change in peak oxygen uptake; secondary outcomes were self-reported and objectively measured physical activity. RESULTS: Out of 83 eligible participants, 76 were available for assessment (68 men/8 women, mean age 59 (8) years) at a one-year follow-up. Peak oxygen uptake was significantly elevated above baseline values, (treadmill exercise: 35.8 (6.4) vs. 37.4 (7.4) ml kg(-1) min(-1) , group exercise: 32.7 (6.5) vs. 34.1 (5.8) ml kg(-1) min(-1) and home-based exercise: 34.5 (4.9) vs. 36.7 (5.8) ml kg(-1) min(-1) at baseline and follow-up, respectively), with no significant differences between groups. The majority of the participants (>90%) met the recommended daily level of 30 minutes of moderate physical activity. The home-based group showed a strong trend towards increased physical activity compared with the hospital-based groups. DISCUSSION: The results from this study have shown that both home-based and hospital-based HIT in cardiac rehabilitation induce promising long-term exercise adherence, with maintenance of peak oxygen uptake significantly above baseline values at a one-year follow-up. The implication for physiotherapy practice is that HIT in cardiac rehabilitation induces satisfactory long-term exercise adherence.

Safety of the CO-Rebreathing Method in Patients with Coronary Artery Disease.

PURPOSE: To address and study the safety concerns with the improved carbon monoxide (CO) rebreathing method for measuring total blood volume in patients with coronary artery disease to implement the use of the methodology in this patient group. METHODS: Eighteen patients with stable coronary artery disease (age 62 ± 7 yr, 24 ± 5 months since diagnosis) were investigated using the improved CO-rebreathing test. Before, during, and up to 2 h after the test, ECG, blood pressure, arterial oxygen saturation, carbon monoxide bound to hemoglobin (HbCO%), and cardiac function were measured. At 24 h, HbCO% and troponin-T were measured. DESIGN: Cross-over. RESULTS: Six minutes after the CO-rebreathing test, HbCO increased from 1.5% ± 0.4% to 6.0% ± 0.6%, with a subsequent decrease to 4.5% ± 0.4% and 1.4% ± 0.4% at 2 h and 24 h after the test, respectively. Resting heart rate, stroke volume, cardiac output, and ejection fraction were 64 ± 11 bpm, 93.9 ± 16.5 mL per beat, 5.84 ± 0.99 L, and 48.5% ± 5.7% and remained unchanged during and 10 min after the rebreathing. All patients were in sinus rhythm during the 2-h observation period, without ST- or T-wave changes, with low numbers of premature beats and normal rate variability. Systolic and diastolic blood pressure gradually decreased during the observation period. Troponin-T was below the 99th percentile for all the participants 24 h after the test. CONCLUSION: Cardiovascular function and safety indices remained unchanged after exposure to approximately 6% HbCO, indicating that the method is safe to perform in patients with stable coronary artery disease.

Treadmill Training or Progressive Strength Training to Improve Walking in People with Multiple Sclerosis? A Randomized Parallel Group Trial.

BACKGROUND AND PURPOSE: The most effective treatment approach to improve walking in people with multiple sclerosis (MS) is not known. The aim of this trial was to assess the efficacy of treadmill training and progressive strength training on walking in people with MS. METHODS: A single blinded randomized parallel group trial was carried out. Eligible participants were adults with MS with Expanded Disability Status Scale score ≤6. A total of 29 participants were randomized and 28 received the allocated exercise intervention, treadmill (n = 13) or strength training (n = 15). Both groups exercised 30 minutes, three times a week for 8 weeks. Primary outcome was The Functional Ambulation Profile evaluated by the GAITRite walkway. Secondary outcomes were walking work economy and balance control during walking, measured by a small lightweight accelerometer connected to the lower back. Testing was performed at baseline and the subsequent week after completion of training. RESULTS: Two participants were lost to follow-up, and 11 (treadmill) and 15 (strength training) were left for analysis. The treadmill group increased their Functional Ambulation Profile score significantly compared with the strength training group (p = .037). A significant improvement in walking work economy (p = .024) and a reduction of root mean square of vertical acceleration (p = .047) also favoured the treadmill group. DISCUSSION: The results indicate that task-specific training by treadmill walking is a favourable approach compared with strength training to improve walking in persons with mild and moderate MS. Implications for Physiotherapy practice, this study adds knowledge for the decision of optimal treatment approaches in people with MS. Copyright © 2015 John Wiley & Sons, Ltd.

Physical therapy intervention in patients with non-cardiac chest pain following a recent cardiac event: A randomized controlled trial.

OBJECTIVES: To assess the effect of two different physical therapy interventions in patients with stable coronary heart disease and non-cardiac chest pain. METHODS: A randomized controlled trial was carried out at a university hospital in Norway. A total of 30 patients with known and stable coronary heart disease and self-reported persistent chest pain reproduced by palpation of intercostal trigger points were participating in the study. The intervention was deep friction massage and heat pack versus heat pack only. The primary outcome was pain intensity after the intervention period and 3 months after the last treatment session, measured by Visual Analogue Scale, 0 to 100. Secondary outcome was health-related quality of life. RESULTS: Treatment with deep friction massage and heat pack gave significant pain reduction compared to heat pack only (-17.6, 95% confidence interval: -30.5, -4.7; p < 0.01), and the reduction was persistent at 3 months' follow-up (-15.2, 95% confidence interval: -28.5, -1.8; p = 0.03). Health-related quality of life improved in all three domains in patients with no significant difference between groups. CONCLUSION: Deep friction massage combined with heat pack is an efficient treatment of musculoskeletal chest pain in patients with stable coronary heart disease.

Does rating of perceived exertion result in target exercise intensity during interval training in cardiac rehabilitation? A study of the Borg scale versus a heart rate monitor.

OBJECTIVES: To assess whether rating of perceived exertion using the Borg 6-20 scale is a valid method for achieving target exercise intensity during high-intensity interval training in cardiac rehabilitation. DESIGN: A single-group cross-over design. METHODS: Ten participants (56 (6.5) years) who were enrolled in a high-intensity interval training cardiac rehabilitation program were recruited. A target exercise intensity of Borg 17 (very hard) was used for exercise intensity guidance in the initial four exercise sessions that took place before a cardiopulmonary exercise test, as in usual care rehabilitation. The heart rate was recorded and blinded to the participants. After performing the test, the participants were then instructed using heart rate monitors openly for exercise guidance in four subsequent exercise sessions, at an intensity corresponding to 85-95% of peak heart rate. RESULTS: The mean exercise intensity during high-intensity bouts was 82% (6%) of peak heart rate for the rating of perceived exertion and 85% (6%) using heart rate monitors (p=0.005). Bland-Altman limits of agreement analysis with a mean bias showed a bias of 2.97 (-2.08, 8.02) percentage points for the two methods. Exercise intensity was highly repeatable with intra-class correlations of 0.95 (95% CI 0.86-0.99, p<0.001) and 0.96 (95% CI 0.88-0.99, p<0.001) in the exercise sessions using rating of perceived exertion and percentage of peak heart rate for intensity control, respectively. CONCLUSIONS: Rating of perceived exertion results in an exercise intensity below target during high-intensity interval training bouts in cardiac rehabilitation. Heart rate monitoring should be used for accurate intensity guidance.

The higher the better? Interval training intensity in coronary heart disease.

OBJECTIVES: Peak oxygen uptake (VO2 peak) increases more after high intensity interval training compared to isocaloric moderate exercise in patients with coronary heart disease (CHD). We assessed the impact of exercise intensity during high intensity intervals on the increase in VO2 peak. DESIGN/METHODS: We included 112 patients with coronary heart disease who had participated in randomized trials of interval training consisting of four times four minutes intervals at 85-95% of heart rate maximum (HRmax) for 12 weeks. Exercise intensity was calculated for each patient using HR during the two last minutes of each interval, expressed as percentage of HRmax. We used a univariate general linear model with VO2 peak increase as the dependent variable and percentage of HRmax, age, number of exercise sessions, and baseline VO2 peak as covariates. Exercise intensity was also divided into three categories; <88%, 88-92%, and >92% of HRmax, and these categories were used as a fixed factor in the model. RESULTS: VO2 peak increased by 3.9 (SD 3.1) mL kg(-1)min(-1), equal to 11.9% after 23.4 exercise sessions. Percentage of HRmax had a significant effect on increase in VO2 peak, both as a continuous (p=0.019) and categorical variable (p=0.020). The estimated marginal means and 95% confidence intervals of the increase in VO2 peak for the three intensity categories were 3.1 (2.0, 4.2), 3.6 (2.8, 4.4), and 5.2 (4.1, 6.3) for the <88%, the 88-92%, and the >92% category, respectively. CONCLUSIONS: Even within the high intensity training zone, exercise intensity was an important determinant for improving VO2 peak in patients with coronary heart disease.

High-intensity aerobic interval training for patients 3-9 months after stroke: a feasibility study.

BACKGROUND AND PURPOSE: High-intensity aerobic interval training (AIT) has shown to be beneficial in patients with cardiac and pulmonary diseases. Presumably, patients with stroke also benefit from such treatment. However, the feasibility and potential efficacy of high-intensity AIT should be investigated for patients early after stroke. METHODS: This was a single-group, pre-test-post-test, intervention study. The intervention consisted of a 6-week high-intensity AIT programme, performed twice a week. The AIT comprised 4 × 4-minute intervals, at 85-95% of peak heart rate, interrupted by 3-minute active breaks. Adherence to the protocol, compliance and adverse events were registered to assess feasibility. Cardiorespiratory fitness and functional outcomes were assessed before and after the intervention and at 6 and 12 weeks follow-up. RESULTS: Ten men and five women (mean age 70.0 ± 7.7; range 61-85 years) with mild to moderate stroke were included, 3-9 months after onset. One patient was diagnosed with cancer during follow-up. There were three minor events, but no serious adverse events occurred. All patients accomplished all training sessions and reached the 85% intensity level, except one patient who discontinued the last session. The mean peak oxygen uptake showed no significant improvement from pre-treatment, 28.7 ± 3.8 ml kg(-1) min(-1), to post-treatment, 29.6 ± 3.6 ml kg(-1) min(-1), p = 0.189, whereas the mean 6-minute walk test improved from 410.7 ± 101.4 m to 461.0 ± 99.6 m, p = 0.001, and the median (interquartile range) Rivermead Motor Assessment Scale improved from 12.0 (11.0-13.0) to 13.0 (11.0-13.0) points, p = 0.100. These improvements continued after the intervention was concluded. CONCLUSIONS: This study has shown that high-intensity AIT is feasible for a selected group of stroke patients. However, the training should be accomplished in line with the American College of Sports Medicine guidelines for high-risk populations to ensure safety. The participants achieved a clinically highly significant improvement in walking distance. This intervention should be tested out in a randomized controlled trial to assess if it is superior to other interventions.

Home-based versus hospital-based high-intensity interval training in cardiac rehabilitation: a randomized study.

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 randomized clinical study. METHODS: Ninety participants with coronary artery disease (80 men/10 women, mean age 57 ± 8 years) were randomly 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 settings of cardiac rehabilitation, with respect to target exercise intensity, exercise attendance, and increase in peak VO2. Exercise mode was not essential for exercise capacity.

Aerobic interval training reduces blood pressure and improves myocardial function in hypertensive patients.

AIMS: Exercise is recommended as prevention, management, and control of all stages of hypertension. There are still controversies about the optimal training dose, frequency, and intensity. We aimed to study the effect of aerobic interval training on blood pressure and myocardial function in hypertensive patients. METHODS AND RESULTS: A total of 88 patients (52.0 ± 7.8 years, 39 women) with essential hypertension were randomized to aerobic interval training (AIT) (>90% of maximal heart rate, correlates to 85-90% of VO(2max)), isocaloric moderate intensity continuous training (MIT) (~70% of maximal heart rate, 60% of VO(2max)), or a control group. Exercise was performed on a treadmill, three times per week for 12 weeks. Ambulatory 24-hour blood pressure (ABP) was the primary endpoint. Secondary endpoints included maximal oxygen uptake (VO(2max)), mean heart rate/24 hour, flow mediated dilatation (FMD), total peripheral resistance (TPR), and myocardial systolic and diastolic function by echocardiography. Systolic ABP was reduced by 12 mmHg (p < 0.001) in AIT and 4.5 mmHg (p = 0.05) in MIT. Diastolic ABP was reduced by 8 mmHg (p < 0.001) in AIT and 3.5 mmHg (p = 0.02) in MIT. VO(2max) improved by 15% (p < 0.001) in AIT and 5% (p < 0.01) in MIT. Systolic myocardial function improved in both exercise groups, diastolic function in the AIT group only. TPR reduction and increased FMD were only observed in the AIT group. CONCLUSIONS: This study indicates that the blood pressure reducing effect of exercise in essential hypertension is intensity dependent. Aerobic interval training is an effective method to lower blood pressure and improve other cardiovascular risk factors.