High-intensity Aerobic Interval Training Research Articles

Time-restricted eating and supervised exercise for improving hepatic steatosis and cardiometabolic health in adults with obesity: protocol for the TEMPUS randomised controlled trial

IntroductionMetabolic dysfunction-associated steatotic liver disease is a major public health problem considering its high prevalence and its strong association with extrahepatic diseases. Implementing strategies based on an intermittent fasting approach...

High-intensity aerobic, but not resistance or combined, exercise training improves both cardiometabolic health and skeletal muscle mitochondrial dynamics.

This study investigated how different exercise training modalities influence skeletal muscle mitochondrial dynamics. Healthy [average body mass index (BMI): 25.8 kg/m2], sedentary younger and older participants underwent 12 wk of supervised high-intensity aerobic interval training (HIIT; n = 13), resistance training (RT; n = 14), or combined training (CT; n = 11). Mitochondrial structure was assessed using transmission electron microscopy (TEM). Regulators of mitochondrial fission and fusion, cardiorespiratory fitness (V̇o2peak), insulin sensitivity via a hyperinsulinemic-euglycemic clamp, and muscle mitochondrial respiration were assessed. TEM showed increased mitochondrial volume, number, and perimeter following HIIT (P < 0.01), increased mitochondrial number following CT (P < 0.05), and no change in mitochondrial abundance after RT. Increased mitochondrial volume associated with increased mitochondrial respiration and insulin sensitivity following HIIT (P < 0.05). Increased mitochondrial perimeter associated with increased mitochondrial respiration, insulin sensitivity, and V̇o2peak following HIIT (P < 0.05). No such relationships were observed following CT or RT. OPA1, a regulator of fusion, was increased following HIIT (P < 0.05), whereas FIS1, a regulator of fission, was decreased following HIIT and CT (P < 0.05). HIIT also increased the ratio of OPA1/FIS1 (P < 0.01), indicative of the balance between fission and fusion, which positively correlated with improvements in respiration, insulin sensitivity, and V̇o2peak (P < 0.05). In conclusion, HIIT induces a larger, more fused mitochondrial tubular network. Changes indicative of increased fusion following HIIT associate with improvements in mitochondrial respiration, insulin sensitivity, and V̇o2peak supporting the idea that enhanced mitochondrial fusion accompanies notable health benefits of HIIT.NEW & NOTEWORTHY We assessed the effects of 12 wk of supervised high-intensity interval training (HIIT), resistance training, and combined training (CT) on skeletal muscle mitochondrial abundance and markers of fission and fusion. HIIT increased mitochondrial area and size and promoted protein changes indicative of increased mitochondrial fusion, whereas lessor effects were observed after CT and no changes were observed after RT. Furthermore, increased mitochondrial area and size after HIIT associated with improved mitochondrial respiration, cardiorespiratory fitness, and insulin sensitivity.

Aerobic high-intensity intervals improve V̇O2max more than supramaximal sprint intervals in females, similar to males.

Maximal oxygen uptake (V̇O2max ) is a pivotal factor for aerobic endurance performance. Recently, aerobic high-intensity interval training (HIIT) was documented to be superior to sprint interval training (SIT) in improving V̇O2max in well-trained males. However, as mounting evidence suggests that physiological responses to training are sex-dependent, examining the effects of HIIT versus SIT on V̇O2max , anaerobic capacity, and endurance performance in females is warranted. We randomized 81 aerobically well-trained females (22 ± 2 years, 51.8 ± 3.6 mL∙kg-1 ∙min-1 V̇O2max ), training three times weekly for 8 weeks, to well-established protocols: (1) HIIT 4 × 4 min at ~95% of maximal aerobic speed (MAS), with 3 min active recovery (2) SIT 8 × 20 s at ~150% of MAS, with 10 s passive recovery (3) SIT 10 × 30 s at ~175% of MAS, with 3.5 min active recovery. Only HIIT 4 × 4 min increased V̇O2max (7.3 ± 3.1%), different from both SIT groups (all p < 0.001). Anaerobic capacity (maximal accumulated oxygen deficit) increased following SIT 8 × 20 s (6.5 ± 10.5%, p < 0.05), SIT 10 × 30 s (14.4 ± 13.7%, p < 0.05; different from HIIT 4 × 4 min, p < 0.05). SIT 10 × 30 s resulted in eight training-induced injuries, different from no injuries following HIIT 4 × 4 min and SIT 8 × 20 s (p < 0.001). All groups improved long-distance (3000-meter) and sprint (300-meter) running performance (all p < 0.001). SIT protocols improved sprint performance more than HIIT 4 × 4 min (p < 0.05). Compared to previous male results, no increase in V̇O2max following SIT 8 × 20 s (p < 0.01), and a higher injury rate for SIT 10 × 30 s (p < 0.001), were evident. In aerobically well-trained women, HIIT is superior to SIT in increasing V̇O2max while all-out treadmill running SIT is potentially more harmful.

Resistance exercise training augments the immunomodulatory adaptations to aerobic high-intensity interval training

ABSTRACT To compare the effectiveness of different types of high-intensity interval training (HIIT) on meta-inflammation during obesity, TLR4 pathway activities were assessed following a 10-week randomized trial. 30 young females with overweight and obesity were randomly allocated to aerobic HIIT (HIIT/AE) or resistance exercise in HIIT (HIIT/RE) and performed a 28-minute (4 × 4 min) in each session. During each interval, the HIIT/AE performed four minutes of all-extremity cycling, whereas the HIIT/RE completed four minutes of combined resistance exercises and all-extremity cycling. The TLR4 pathway gene expression was measured for the TLR4 receptor, downstream adaptors (TIR domain-containing adaptor-inducing interferon-β (TRIF) and myeloid differentiation factor (MYD) 88), transcriptional factors (nuclear factor kappa B (NF-κB), and interferon regulatory factor (IRF) 3), and its negative regulator (tumor necrosis factor (TNF) a-induced protein 3 (TNFAIP3)). The serum levels of TNFα, interferon (IFN) γ, interleukin (IL)-10, and adiponectin were measured. We found that TLR4 (HIIT/RE: 0.6 ± 0.43 vs. HIIT/AE: 1.24 ± 0.82, p = 0.02), TRIF (HIIT/RE: 0.51 ± 0.4 vs. HIIT/AE: 3.56 ± 0.52, p = 0.001), and IRF3 (HIIT/RE: 0.49 ± 0.42 vs. HIIT/AE: 0.6 ± 0.89; p = 0.04) levels were significantly downregulated in HIIT/RE compared to the HIIT/AE, with a significant reduction in serum levels of TNFα (pg/ml) (HIIT/RE: 22.5 ± 11.3 to 6.3 ± 5.3 vs. HIIT/AE: 19.16 ± 20.8 to 13.48 ± 21.7, p = 0.04) and IFNγ (pg/ml) (HIIT/RE: 43.5 ± 20.6 to 37.5 ± 4.3 vs. HIIT/AE: 37.6 ± 5.6 to 68.1 ± 22.5, p = 0.03). Adiponectin and IL-10 levels did not significantly differ between the two groups. Thus, resistance exercise training augments the immunomodulatory adaptations to HIIT and should be prescribed to people at risk of cardiometabolic disease. Highlights HIIT in combination with resistance exercise looks more effective than HIIT alone to target TLR4-mediated inflammation in individuals with overweight and obesity. HIIT/RE induces a different effect on two downstream cascades of TLR4, leading to a greater overall reduction of TRIF-dependent pathway activities compared to MYD88. Both HIIT protocols show comparable effects on the negative regulatory protein TNFAIP3 gene expression.

Experiences with physical activity, health and well-being among young adults with serious mental illness

ABSTRACT Purpose To explore how young adults with serious mental illness (SMI) experience physical activity and how these experiences influence their perceived health and well-being. Methods Nine young adults with SMI who had participated in an aerobic high-intensity interval training program were interviewed in depth. The interviews were transcribed and subjected to reflexive thematic analysis. Results The results indicated that people with SMI mainly experience physical activity as a meaningful activity that contributes to an increased sense of well-being and better health. However, to overcome various barriers, it is crucial to experience social support and encouragement. The following three main themes were identified through reflexive thematic analysis: (1) positive changes in focus and an increase in well-being occur through physical activity; (2) increased mental strength results from physical activity; and (3) a lack of support and feelings of safety prevent physical activity. Conclusions This study shows that adapted physical activity is an important resistance resource that can promote stronger self-identity, increased mental well-being and social engagement and thus contribute to an improved ability to manage stressors. Furthermore, the findings reveal that to engage in physical activity and promote sustainable life changes, it is important for individuals to choose a physical activity based on personal interest and meaning.

Effects of Exercise Intensity on Cardiometabolic Parameters of Ovariectomized Obese Mice.

The aim of this study was to compare the effects of continuous-moderate vs. high-intensity interval aerobic training on cardiovascular and metabolic parameters in ovariectomized high-fat-fed mice. C57BL/6 female ovariectomized were divided into four groups (n=8): low-fat-fed sedentary (SLF); high-fat-fed sedentary (SHF); high-fat-fed moderate-intensity continuous trained (MICT-HF); and high-fat-fed high-intensity interval aerobic trained (HIIT-HF). The high-fat diet lasted 10 weeks. Ovariectomy was performed in the fourth week. The exercise training was carried out in the last four weeks of protocol. Fasting glycemia, oral glucose tolerance, arterial pressure, baroreflex sensitivity, and cardiovascular autonomic modulation were evaluated. Moderate-intensity continuous training prevented the increase in arterial pressure and promoted a reduction in HR at rest, associated with an improvement in the sympathovagal balance in MICT-HF vs. SHF. The high-intensity interval training reduced blood glucose and glucose intolerance in HIIT-HF vs. SHF and MICT-HF. In addition, it improved sympathovagal balance in HIIT-HF vs. SHF. Moderate-intensity continuous training was more effective in promoting cardiovascular benefits, while high-intensity interval training was more effective in promoting metabolic benefits.

Improving Cognitive Function Through High-Intensity Interval Training in Breast Cancer Patients Undergoing Chemotherapy: Protocol for a Randomized Controlled Trial

More than 75% of patients with breast cancer treated with chemotherapy experience cognitive impairments (eg, memory and attention problems), commonly known as chemo-brain. Exercise, especially aerobic high-intensity interval training (HIIT), is associated with better cognitive function in healthy populations. However, clinical trials testing the impact of exercise interventions on chemotherapy-induced cognitive decline in patients with cancer are lacking, and the mechanisms through which exercise could improve cognitive function are unclear. The objective of the Improving Cognitive Function Through High-Intensity Interval Training in Breast Cancer Patients Undergoing Chemotherapy trial is to examine the effects of HIIT on cognitive function in patients with breast cancer undergoing chemotherapy. This 2-arm, single-center, pilot randomized controlled trial will randomize 50 patients with breast cancer undergoing chemotherapy to HIIT or attention control. The HIIT group will perform a supervised 16-week, thrice-weekly intervention, with each session including a 5-minute warm-up at 10% maximal power output (POmax), 10 sets of alternating 1-minute high-intensity (90% POmax) and 1-minute recovery (10% POmax) intervals, and a 5-minute cooldown (10% POmax). The attention control group will receive a stretching program with no exercise components and be asked to maintain their exercise levels for 16 weeks. The primary outcomes of the study are executive function and memory measured using the National Institutes of Health toolbox and resting-state connectivity and diffusion tensor imaging microstructure evaluated using magnetic resonance imaging. The secondary and tertiary outcomes include cardiorespiratory fitness, body composition, physical fitness, and psychosocial health. The study has been approved by the institutional review board of the Dana-Farber Cancer Institute (20-222). The trial was funded in January 2019, with recruitment started in June 2021. As of May 2022, a total of 4 patients have consented and been randomized (n=2, 50% to exercise; n=1, 25% to control; and n=1, 25% nonrandomized). Trial completion is expected in January 2024. This first-of-its-kind study incorporates a novel exercise intervention (ie, HIIT) and comprehensive cognitive measures. If positive, our findings will establish the pilot efficacy of HIIT on chemotherapy-induced cognitive function in patients with breast cancer, providing the foundation for future larger phase-II and phase-III trials to confirm the findings and potentially establish HIIT as a standard of care for women undergoing chemotherapy for breast cancer. ClinicalTrials.gov NCT04724499; https://clinicaltrials.gov/ct2/show/NCT04724499. DERR1-10.2196/39740.

Aerobic high-intensity interval exercise training in patients with angina and no obstructive coronary artery disease: feasibility and physiological effects.

Patients with chest pain and normal coronary angiogram [angina with normal coronary arteries (ANOCA)] constitute a therapeutic problem with considerable functional limitation and reduced quality of life. The aims of the current pilot study were to (i) explore if a structured aerobic high-intensity interval training (HIT) program for 12 weeks was feasible in patients with ANOCA, and (ii) to assess mechanisms related to symptoms in this population. Sixteen patients with ANOCA underwent a 3-month aerobic HIT program with one-to-one monitored exercise sessions on treadmill in a 4 min × 4 manner, three times a week. Four patients served as controls. Coronary flow velocity reserve (CFVR) transthoracic Doppler, flow-mediated vasodilation (FMD) and VO2max was measured at baseline and after 12 weeks. The average attendance to training sessions was 82.3% ± 10.1 (56-94). CFVR in the training group increased from 2.50 ± 0.48 to 3.04 ± 0.71 (P < 0.001) whereas FMD increased from 4.19 ± 2.42% to 8.28 ± 2.85% (P < 0.001). Improvement in CFVR correlated with the relative improvement in FMD (R = 0.45, P = 0.047). This was associated with an increase in VO2max from 28.75 ± 6.51 mL/kg/min to 31.93 ± 6.46 mL/kg/min (P < 0.001). A 3-month program of monitored HIT was feasible, with high adherence resulting in improved functional capacity in patients with ANOCA. CFVR improved and this improvement was associated with improved FMD. NCT02905630.

Low-Volume and High-Intensity Aerobic Interval Training May Attenuate Dysfunctional Ventricular Remodeling after Myocardial Infarction: Data from the INTERFARCT Study

Background: Aerobic high-intensity interval training (HIIT) has demonstrated benefits for ventricular remodeling after myocardial infarction (MI) through various mechanisms. Despite this, the optimal training volume is not well known. The present study aimed to assess the effects of different (low vs. high volume) aerobic HIIT compared to an attentional control (AC) group on echocardiographic and biochemical indicators of left ventricular (LV) remodeling in adults after MI. Methods: Randomized clinical trial conducted on post-MI patients with preserved ventricular function. Participants were assigned to three study groups. Two groups performed HIIT 2 d/week, one group with low-volume HIIT (20 min, n = 28) and another with high-volume HIIT (40 min, n = 28). A third group was assigned to AC (n = 24) with recommendations for unsupervised aerobic training. Left ventricular echocardiographic parameters and cardiac biomarker levels (N-terminal pro-b-type natriuretic peptide, NT-proBNP; soluble growth stimulation expressed gene 2, ST2; troponin T; and creatine kinase) were assessed at baseline and after the intervention (16 weeks). Results: Eighty participants (58.4 ± 8.3 yrs, 82.5% male) were included. Both low- and high-volume HIIT showed increases (p &lt; 0.05) in left ventricular end-diastolic diameter (1.2%, 2.6%), and volume (1.1%, 1.3%), respectively. Interventricular septal and posterior walls maintained their thickness (p = 0.36) concerning the AC. Significant (p &lt; 0.05) gain in diastolic function was shown with the improvements in E (–2.1%, –3.3%), e’ waves (2.2%, 5.5%), and the deceleration time (2.1%, 2.9%), and in systolic function with a reduction in global longitudinal strain (–3.2%, –4.7%), respectively. Significant (p &lt; 0.05) reductions of N-terminal pro-B-type natriuretic peptide (NT-proBNP) (–4.8%, –11.1%) and of ST2 (–21.7%, –16.7%)were found in both HIIT groups respectively compared to the AC group. Creatine kinase elevation was shown only in high-volume HIIT (19.3%, p &lt; 0.01). Conclusions: Low-volume HIIT is proposed as a clinically time-efficient and safer strategy to attenuate dysfunctional remodeling by preventing wall thinning and improving LV function in post-MI patients.

Effect of Exercise on Arterial Stiffness in Healthy Young, Middle-Aged and Older Women: A Systematic Review.

Arterial stiffness, an age-dependent phenomenon, is improved with exercise, which in turn may prevent cardiovascular diseases in women. However, there is a lack of consolidated information on the impact of exercise on arterial stiffness among healthy women. The aim of this review was to (i) analyse the effect of exercise on arterial stiffness in healthy young, middle-aged, and older women, and (ii) recommend types, intensity, and frequency for each age group. Database searches on PubMed, ScienceDirect, Web of Science, and Scopus were conducted using PRISMA guidelines until September 2022. The keywords were: exercise, women/female, and arterial stiffness. The inclusion criteria were: healthy women, supervised exercise, and arterial stiffness measures. Study quality and bias were assessed using the PEDro scale. Fifty-one papers were classified into young (n = 15), middle-aged (n = 14), and older (n = 22) women. Improvements in arterial stiffness were observed among: young women (Pulse Wave Velocity, PWV: 4.9-6.6 m/s), following an 8-week high-intensity aerobic (3 days/week) or hypoxic high-intensity interval training; middle-aged women (PWV: 5.1-7.9 m/s), aerobic exercise with moderate intensity or stretching exercise at "moderate to heavy" (Borg Scale), 20-30 s per site, 10 s of rest interval for 30 min; and for older women (PWV: 7.9-15.6 m/s), resistance training at light intensity, aerobic exercise at any intensity, or a combination of the two exercises. This review shows that arterial stiffness increases with age in healthy women and has an inverse relationship with exercise intensity. Therefore, when prescribing exercise to improve arterial stiffness, age and arterial stiffness measures should be accounted for.

The effect of high-intensity interval training on cognitive function in patients with substance use disorder: Study protocol for a two-armed randomized controlled trial.

Substance use disorder (SUD) is characterized by cognitive impairment, especially executive dysfunction. Executive function is recognized as an important determinant of treatment outcome as it is associated with dropout rate, attendance to therapy and potential relapse after treatment termination. Physical activity can have beneficial effects on cognitive function, but there is still a lack of knowledge regarding potential benefits of aerobic exercise for executive function in SUD treatment. The aim of this study is to examine the effect of aerobic high-intensity interval training (HIIT) on cognitive function and the subsequent effect on treatment outcome in patients with SUD. This study is a randomized controlled trial, including men and women ≥18 years with diagnosed SUD by ICD-10. The patients will be recruited from the department for inpatient treatment at Blue Cross - Lade Addiction Treatment Center, Trondheim, Norway. Participants will be randomized 1:1 into either HIIT (3x/week) + treatment as usual (TAU), or TAU alone. Study outcomes will be assessed at baseline, after eight weeks of intervention, and at 3- and 12-months follow-up. The primary outcome is to compare the change in executive function (via altered BRIEF-A score, Behavior Rating Inventory of Executive Function-Adult) measured between the two study groups after eight weeks. Secondary outcomes include mapping of cognitive function in different subgroups (e.g. type of substance, age, fitness level), collecting self-reported information about quality of life, craving, sleep quality, etc., as well as assessing compliance to TAU and long-term treatment outcome. The project was approved by the Regional Ethical Committee and will be performed in accordance with this protocol and the Declaration of Helsinki. Written informed consent will be obtained from all participants prior to inclusion. This project will explore a novel approach to how exercise can be applied in SUD treatment, beyond the well-known effects on physical health. We expect to achieve new knowledge in regard to what extent HIIT can improve cognitive abilities and subsequent treatment outcome in SUD. https://www.clinicaltrials.gov/NCT05324085.

Study protocol for the BRAIN Training Trial: a randomised controlled trial of Balance, Resistance, And INterval training on cognitive function in older adults with mild cognitive impairment

IntroductionEpidemiological evidence suggests that both poor cardiovascular fitness and low muscle mass or strength markedly increase the rate of cognitive decline and incident dementia in older adults. Results from exercise...

Effects of High-Intensity Aerobic Interval Training on Cardiopulmonary Function in Patients With Chronic Heart Failure at The University Teaching Hospital, Lusaka, Zambia

Chronic heart failure patients present with a wide variety of symptoms such as, fatigue and dyspnea, which adversely affect their quality of life. Heart failure is a complex disease and a major cause of morbidity and mortality in developed and developing countries including Zambia. Through studies undertaken, high intensity aerobic interval training has been recommended in patients with chronic heart failure, to help improve symptoms and consequently the quality of life. Minimal research pertaining to effectiveness of aerobic exercise on various physiological parameters such as peripheral oxygen saturation, cardiopulmonary capacity and quality of life have been done in Africa and Zambia. Methods: This study evaluated the physiological effects of high intensity aerobic interval training on the cardiopulmonary function in New York Heart Association (NYHA) Class II and III chronic heart failure patients with a focus on peripheral oxygen delivery/saturation, cardiopulmonary capacity and the quality of life. This study utilised the Randomised Clinical Trial (RCT) study design and the study population was selected from the University Teaching Hospital-Heart clinic in Lusaka, Zambia. Results: A total number of 42 patients participated, and were randomly assigned to the two arms of the study. Twenty-one (21) were assigned to the interventional group (IG) and 21 to the control group (CG) respectively. The IG underwent a 12 week aerobic HIIT exercise-training program, while the CG was subjected to 30 minutes’ walk on a treadmill for the same period of 12 weeks. The expected primary outcomes were the baseline to endline differences in oxygen delivery/saturation readings, cardiopulmonary capacity test readings and the quality of life (measured using the Minnesota questionnaire) for both groups. The results obtained from the pulse oximeter readings, showed an increase in the oxygen saturation readings (97.90 to 98.62%), 6-minute walk distance readings (360.05 m to 429 m) and the questionnaire score totals of the different dimensions (physical, emotional/mental and socio-psychological factors) of the questionnaire (p-value ;0.0001) of the IG. The CG oxygen saturation readings (97.38 % to 97.90%) and 6-minute walk tests scores (359.14 to 370.9 m) showed minimal change. While, the questionnaire scores showed a statistical difference in the emotional/mental (p-value &lt; 0.0001), physical (p=0.005) and socio-psychological factors (p- value &lt; 0.0001). Conclusion: High intensity aerobic interval training has shown to improve the peripheral oxygen delivery, cardiopulmonary capacity and quality of life in chronic heart failure patients hence, must be considered as an adjunct therapy aside pharmacological management in stable chronic heart failure patients in Zambia.

Effects of supervised high-intensity interval training on motivational outcomes in men with prostate cancer undergoing active surveillance: results from a randomized controlled trial

BackgroundUnderstanding the motivational effects of supervised aerobic high-intensity interval training (HIIT) may help men with prostate cancer undergoing active surveillance initiate and maintain exercise behavior, however, few studies have addressed this question. This report explored exercise motivation in men with prostate cancer undergoing active surveillance participating in a randomized exercise trial.MethodsThe Exercise during Active Surveillance for Prostate Cancer (ERASE) trial randomized 52 men with prostate cancer on active surveillance to the HIIT exercise group or the usual care (UC) group. The exercise program was supervised aerobic HIIT conducted three times per week for 12 weeks. The motivation questions were developed using the Theory of Planned Behavior and included motivational constructs, anticipated and experienced outcomes, and barriers to HIIT during active surveillance.ResultsThe HIIT group attended 96% of the planned exercise sessions with 100% compliance to the exercise protocol. Motivation outcome data were obtained in 25/26 (96%) participants in the HIIT group and 25/26 (96%) participants in the UC group. At baseline, study participants were generally motivated to perform HIIT. After the intervention, the HIIT group reported that HIIT was even more enjoyable (p < 0.001; d = 1.38), more motivating (p = 0.001; d = 0.89), more controllable (p < 0.001; d = 0.85), and instilled more confidence (p = 0.004; d = 0.66) than they had anticipated. Moreover, compared to UC, HIIT participants reported significantly higher perceived control (p = 0.006; d = 0.68) and a more specific plan (p = 0.032; d = 0.67) for performing HIIT over the next 6 months. No significant differences were found in anticipated versus experienced outcomes. Exercise barriers were minimal, however, the most often reported barriers included pain or soreness (56%), traveling to the fitness center (40%), and being too busy and having limited time (36%).ConclusionMen with prostate cancer on active surveillance were largely motivated and expected significant benefits from a supervised HIIT program. Moreover, the men assigned to the HIIT program experienced few barriers and achieved high adherence, which further improved their motivation. Future research is needed to understand long-term exercise motivation and behavior change in this setting.Trial registrationClinicaltrials.gov, NCT03203460. Registered on June 29, 2017.

Effects of moderate-continuous and high-intensity interval aerobic training on cardiac function of spontaneously hypertensive rats.

The aim of this study was to verify the effects of moderate-intensity continuous (MICT) and high-intensity interval (HIIT) aerobic training on cardiac morphology and function and the mechanical properties of single cardiomyocytes in spontaneously hypertensive rats (SHR) in the compensated phase of hypertension. Sixteen-week-old male SHR and normotensive Wistar (WIS) rats were allocated to six groups of six animals each: SHR CONT or WIS CONT (control); SHR MICT or WIS MICT (underwent MICT, 30 min/day, five days per week for eight weeks); and SHR HIIT or WIS HIIT (underwent HIIT, 30 min/day, five days per week for eight weeks). Total exercise time until fatigue and maximum running speed were determined using a maximal running test before and after the experimental period. Systolic (SAP), diastolic (DAP), and mean (MAP) blood pressures were measured using tail plethysmography before and after the experimental period. Echocardiographic evaluations were performed at the end of the experimental period. The rats were euthanized after in vivo assessments, and left ventricular myocytes were isolated to evaluate global intracellular Ca2+ transient ([Ca2+]i) and contractile function. Cellular measurements were performed at basal temperature (~37°C) at 3, 5, and 7 Hz. The results showed that both training programs increased total exercise time until fatigue and, consequently, maximum running speed. In hypertensive rats, MICT decreased SAP, DAP, MAP, interventricular septal thickness during systole and diastole, and the contraction amplitude at 5 Hz. HIIT increased heart weight and left ventricular wall thickness during systole and diastole and reduced SAP, MAP, and the time to peak [Ca2+]i at all pacing frequencies. In conclusion, both aerobic training protocols promoted beneficial adaptations to cardiac morphology, function, and mechanical properties of single cardiomyocytes in SHR.

The Effect of 8 Weeks of High Intensity Training vs High Volume Training on TCF4/CHOP10 Gene Complexes of Subcutaneous Fat Tissue in Male Rats

Background and Objectives This study aims to evaluate the effect of different intensities of aerobic training on the expression of transcription factor 4 (TCF4) and C/EBP homologous protein (CHOP10) genes in subcutaneous adipose tissue of male Wistar rats. Subjects and Methods In this experimental study, 32 male Wistar rats with a mean age of 6 weeks and a weight of 237±33 gr were used. Then, they were randomly divided into four groups of 8, including control group, moderate-intensity aerobic training (MIT), high-intensity aerobic training (HIT), and highintensity interval aerobic training (HIIT). The MIT group trained at an intensity of 65% VO2max for 47 minutes. The HIT group running at a speed of 20 meters per minute with an increasing inclination for 40 minutes. The HIIT group trained at an intensity of 90-100% VO2max for 37 minutes. Adipose tissue sample was collected 24 hours after the last training session to evaluate the expression of TCF4 and CHOP10 genes by real-time PCR method. Results There was a significant difference in the expression of CHOP10 gene in the subcutaneous tissue of male Wistar rats in the HIIT group compared to the MIT and control group (P=0.004). However, no significant difference was observed between HIIT and HIT groups (P=1). In addition, there was a significant difference in TCF4 gene expression in the HIIT group compared to the control group (P=0.006). However, no significant difference was observed between HIIT and HIT groups (P=1) Conclusion The expression level of adipogenic genes decreased after HIIT. These findings indicate that this exercise is effective in controlling the expression of genes involved in fat metabolism.

High-intensity aerobic interval training and resistance training are feasible in rectal cancer patients undergoing chemoradiotherapy: a feasibility randomized controlled study.

BackgroundThere has been growing evidence of the benefits of high-intensity aerobic interval training (HIIT) and resistance training (RES) for populations with cancer. However, these two modalities have not yet been performed alone in rectal cancer patients undergoing neoadjuvant chemoradiotherapy (NACR T). Therefore, this study aimed to determine the feasibility of HIIT and RES in rectal cancer patients undergoing NACR T.Materials and methodsRectal cancer patients set to undergo NACRT were randomly assigned to HIIT intervention, RES intervention, or the usual care. Feasibility of HIIT and RES was assessed by measuring recruitment rate, adherence (retention rate, attendance rate, and exercise sessions duration and intensity), and adverse events. Endpoints (changes in fatigue, health-related quality of life, depression, daytime sleepiness, insomnia, sleep quality, functional exercise capacity, and executive function) were assessed at baseline and at week 5.ResultsAmong the 20 eligible patients, 18 subjects were enrolled and completed the study, yielding a 90% recruitment rate and 100% retention rate. Attendance at exercise sessions was excellent, with 92% in HIIT and 88% in RES. No exercise-related adverse events occurred.ConclusionThis study demonstrated that HIIT and RES are feasible in rectal cancer patients undergoing NACR T.Trial registrationwww.clinicaltrials.gov, NCT03252821 (date of registration: March 30, 2017)

Impact of Aerobic High-Intensity Interval Training Intervention and Mediterranean Diet Recommendations on Health-Related Quality of Life and Lifestyle Modification in Post-Myocardial Infarction Patients: Results From the INTERFARCT Surveys.

This study aims to determine the impact of 2 (low vs high volume) high-intensity interval training (HIIT) programs with Mediterranean diet (MedDiet) recommendations on health-related quality of life (HRQoL) and lifestyle modification, and to examine the relationships between the changes in anxiety and depression with HRQoL and lifestyle variables after myocardial infarction (MI). Participants (n = 80) were randomized to attention control or one of the two supervised HIIT groups (2d/weeks). Surveys before and after intervention (16weeks): HRQoL (SF-36), anxiety and depression (HADS), MedDiet adherence (MEDAS), and physical activity (PA) and sedentary behavior (SB) levels. After intervention, there were improvements (P < .05) in HRQoL, HADS scores, and MedDiet adherence, with higher PA level in both HIIT groups with no between-HIIT group differences. The HADS score decline correlated (P < .05) with both the increase in physical component of SF-36 (r = .42), the overall metabolic expenditure (r = .26), and adherence to the MedDiet (r = .24), and the reduction in the SB (r = .35). HIIT exercise intervention with MedDiet recommendations improved HRQoL, along with reduced anxiety and depression symptoms, and a healthier lifestyle after MI. Better mental health was related to higher values of PA and MedDiet adherence.

Comparative analysis of aerobic cardiorespiratory training of high and moderate intensity in cardiac surgery profile patients

Aim. The aim of our study was to conduct a comparative analysis of aerobic high-intensity interval training and constant moderate intensity training in cardiac rehabilitation of adult patients after open-heart surgery, namely after coronary artery bypass grafting (CABG).&#x0D; Material and methods. 137 patients after CABG were included in the study. 90.4% of patients were consider as class I of chronic heart failure after surgery. Cardiorespiratory trainings were initiate in 4 weeks after surgery, using cycling by veloergometers. Two groups were compare according to rehabilitation programs: one carried out constant aerobic trainings of moderate and medium intensity, and the other, aerobic high-intensity interval trainings. Supervised trainings were carry out for 150 minutes per week. Total length of trainings was 47 weeks. Long-term trainings were distantly monitore.&#x0D; Results. Ergospirometric results as well as results of echocardiography were significantly improve after training course. These results were more significant in high-intensity interval training group, compared to moderate intensity-training group. VO2, heart rate and training power significantly improved. Body mass index significantly diminished in high-intensity interval training group, compared to moderate intensity-training group. In 7 weeks after training ominously decreased blood triglycerides and increased high-density lipoproteins.&#x0D; Conclusion. Cardiorespiratory trainings ameliorate mitochondrial biogenesis, carbohydrate and lipid metabolism, promote to reduce abdominal obesity and other crucial risk factors of coronary patients. Aerobic high-intensity interval cardiac trainings are as safe as moderate intensity cardiac trainings, and in some issues, they outperform moderate intensity cardiac trainings.

Interactive Effects of Enalapril Administration and Novel HIIT Wheel-Bed Training in Aged Rats.

Introduction:Growing research suggests that aerobic high-intensity interval training (HIIT) improves cardiovascular function and physical performance compared with moderate intensity continuous training (MICT). However relatively few animal models of HIIT are available to inform about the benefits of this exercise—particularly among older animals. In addition, there is little evidence for how HIIT training interacts with adjuvant pharmacological therapies known to enhance the impact of MCIT in older individuals such as Angiotensin Converting Enzyme (ACE) Inhibitors.Purpose:The aim of the present study was to establish a HIIT protocol in aged rats based on forced running wheel-bed, and to subsequently (1) establish the feasibility of the HIIT protocol in a proof-of-concept study evaluating interactions between HIIT and (2) the result of combining HIIT + ACE inhibitor treatment using the ACE inhibitor enalapril.Methods:Two groups of rats were used in this study. The feasibility of using wheel-bed for HIIT training was tested in group one (15- and 30-month-old male rats). In the second group, 37 24-month-old Fisher 344 × Brown Norway male rats were randomly divided into four subgroups: control, enalapril, HIIT training group, and HIIT training combined with enalapril administration. The training and administration lasted for 4 weeks. After the intervention, locomotor activity, exercise tolerance, and grip strength were tested.Results:Our feasibility study suggested that middle-aged and aged rats were able to successfully complete the HIIT training. In our intervention study, HIIT training alone, regardless of adjuvant enalapril intervention, did raise treadmill exercise tolerance vs. the sedentary condition. Measures of healthspan were not negatively impacted by HIIT training.Conclusion:The novel HIIT protocol based on forced running wheel-bed was successfully employed in aged rats. We conclude that future studies should compare the results and of multi-modal intervention strategies which include both HIIT and MICT in combination with adjuvant therapies such as enalapril to improve exercise tolerance and other global indices of healthspan.