High-intensity Aerobic Interval Research Articles

Acute effect of high-intensity interval aerobic exercise on serum myokine levels and resulting tumour-suppressive effect in trained patients with advanced prostate cancer.

Although skeletal muscle releases cytokines called myokines during exercise, the kinetics of the acute myokine response to exercise (exercise-induced circulatory myokine level alteration) is unknown in patients with advanced prostate cancer. We measured myokine levels in serum obtained from patients with metastatic castrate-resistant prostate cancer (mCRPC) before and after exercise and assessed the growth-suppressive effect of the serum by applying it to a PCa cell line. Nine patients with mCRPC (age = 67.8 ± 10.1 years, time since mCRPC diagnosis 36.2 ± 22.5 months) undertook 34 min of a high-intensity interval exercise session on a cycle ergometer. Blood was collected immediately pre, post and 30 min post. Serum levels of secreted protein acidic and rich in cysteine (SPARC), oncostatin M (OSM), interleukin-6 (IL-6), interleukin-15 (IL-15), decorin, irisin, and IGF-1 were determined. Growth of the androgen-independent PCa cell line DU-145 exposed to serum collected at three points was measured. There was a significant elevation of SPARC (19.9%, P = 0.048), OSM (11.5%, P = 0.001), IL-6 (10.2%, P = 0.02) and IL-15 (7.8%, P = 0.023) in serum collected immediately after exercise compared to baseline, returning to baseline after 30 min rest. A significant reduction in DU-145 Cell growth and the Cell Index area under the curve at 72 h incubation was observed with the presence of serum obtained immediately post-exercise (Cell Index at 72 h: 16.9%, P < 0.001; area under the curve: 15.2%, P < 0.001) and with the presence of serum obtained 30 min post-exercise compared to baseline (Cell Index at 72 h: 6.5%; area under the curve: 8.8%, P < 0.001). This study provides preliminary evidence for an acute exercise-induced myokine response and tumour growth suppression in serum after a bout of high-intensity interval exercise in patients with advanced PCa.

Prescribing and Self-Regulating Heated Water-Based Exercise by Rating of Perceived Exertion in Older Individuals With Hypertension.

We aimed to analyze the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval (HIIE) and moderate-intensity continuous (MICE) aerobic exercise performed in a heated swimming pool (32°C). Fifteen older individuals (65 ± 3years) treated for hypertension underwent a symptom-limited maximal graded exercise test to determine their heart rate at anaerobic threshold, and respiratory compensation point. On different days, participants were randomized to HIIE (walking/jogging between 11 and 17 of RPE; 25min) and MICE (walking at 11-13 of RPE; 30min). Heart rate during the low-intensity intervals of HIIE and MICE remained below the graded exercise test's heart rate at anaerobic threshold (-7 ± 18bpm/-16 ± 15bpm) and respiratory compensation point (-18 ± 18bpm/-30 ± 16bpm), respectively, and maintained in the aerobic training zone during the high-intensity intervals of HIIE (+8 ± 18bpm/-4 ± 19bpm). The RPE scale at 15-17 is a useful tool for prescribing and self-regulating heated water-based HIIE and may have important implications for water-based exercise in older individuals with hypertension.

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.

Late Afternoon Vigorous Exercise Increases Postmeal but Not Overnight Hypoglycemia in Adults with Type 1 Diabetes Managed with Automated Insulin Delivery.

Aim: To compare evening and overnight hypoglycemia risk after late afternoon exercise with a nonexercise control day in adults with type 1 diabetes using automated insulin delivery (AID). Methods: Thirty adults with type 1 diabetes using AID (Minimed 670G) performed in random order 40 min high intensity interval aerobic exercise (HIE), resistance (RE), and moderate intensity aerobic exercise (MIE) exercise each separated by >1 week. The closed-loop set-point was temporarily increased 2 h pre-exercise and a snack eaten if plasma glucose was ≤126 mg/dL pre-exercise. Exercise commenced at ∼16:00. A standardized meal was eaten at ∼20:40. Hypoglycemic events were defined as a continuous glucose monitor (CGM) reading <70 mg/dL for ≥15 min. Four-hour postevening meal and overnight (00:00-06:00) CGM metrics for exercise were compared with the prior nonexercise day. Results: There was no severe hypoglycemia. Between 00:00 and 06:00, the proportion of nights with hypoglycemia did not differ postexercise versus control for HIE (18% vs. 11%; P = 0.688), RE (4% vs. 14%; P = 0.375), and MIE (7% vs. 14%; P = 0.625). Time in range (TIR) (70-180 mg/dL), >75% for all nights, did not differ between exercise conditions and control. Hypoglycemia episodes postmeal after exercise versus control did not differ for HIE (22% vs. 7%; P = 0.219) and MIE (10% vs. 14%; P > 0.999), but were greater post-RE (39% vs. 10%; P = 0.012). Conclusions: Overnight TIR was excellent with AID without increased hypoglycemia postexercise between 00:00 and 06:00 compared with nonexercise days. In contrast, hypoglycemia risk was increased after the first meal post-RE, suggesting the importance of greater vigilance and specific guidelines for meal-time dosing, particularly with vigorous RE. ACTRN12618000905268.

THE EFFECT of HIGH-INTENSITY INTERVAL PHYSICAL TRAINING ON THE ENERGY SUPPLY SYSTEM IN PATIENTS AFTER HEART SURGERY

Introduction. A number of studies have found a reduction in the risk of rehospitalization during cardiorehabilitation after heart surgery. The purpose of the training program for cardiorehabilitation after cardiac surgery is to optimize energy supply systems. Depending on the intensity and duration of the load being performed, energy supply systems 'switch on' in the body.Purpose of the study: to study the effectiveness of the optimal cardiorehabilitation training program on the aerobic energy supply system in cardiac surgery patients.Materials and methods. In our study, we examined 47 patients who underwent aortic valve replacement under cardiopulmonary bypass, with an EC duration of 52±20.5 minutes. The patients were divided into two groups: the control group (n=23), who underwent a course of cardiorehabilitation on exercise bikes with constant aerobic training of moderate and medium intensity, at the age of 50.2±3.4 years, and the main group (n=24) – with a course of cardiorehabilitation on exercise bikes with aerobic high-intensity interval physical training, at the age of 51.2±2.8 years (p&gt;0.05). Gender was not taken into account. Anaerobic training was carried out on SCHILLER exercise bikes from day 14 after aortic valve replacement. The load power ranged from 25 to 70–95 watts. Before cardiac rehabilitation, the level of lactate, glucose, pH, pCO2, pO2, BE, lipid profile, BNP in the blood before and after ergometric exercise, data on external respiration, heart rate and blood pressure were assessed. After the course of rehabilitation, the above parameters were evaluated. The duration of the course was 2 weeks. Results. When evaluating the indicators at the end of the course of cardiorehabilitation was being done, a significant decrease in the controlled parameters after training was observed in both groups, and largely in the group of high-intensity interval physical training than in the group of constant training of medium intensity.Conclusions. Analysis of the results showed that properly selected parameters of high-intensity interval training could optimize anaerobic glycolysis in patients undergoing operations under cardiopulmonary bypass, as well as increase the functionality of patients. As more and more repetitions of the load are performed, interval training becomes more and more aerobic.

Implementation of exercise countermeasures during spaceflight and microgravity analogue studies: Developing countermeasure protocols for bedrest in older adults (BROA).

Significant progress has been made in the development of countermeasures to attenuate the negative consequences of prolonged exposure to microgravity on astronauts’ bodies. Deconditioning of several organ systems during flight includes losses to cardiorespiratory fitness, muscle mass, bone density and strength. Similar deconditioning also occurs during prolonged bedrest; any protracted time immobile or inactive, especially for unwell older adults (e.g., confined to hospital beds), can lead to similar detrimental health consequences. Due to limitations in physiological research in space, the six-degree head-down tilt bedrest protocol was developed as ground-based analogue to spaceflight. A variety of exercise countermeasures have been tested as interventions to limit detrimental changes and physiological deconditioning of the musculoskeletal and cardiovascular systems. The Canadian Institutes of Health Research and the Canadian Space Agency recently provided funding for research focused on Understanding the Health Impact of Inactivity to study the efficacy of exercise countermeasures in a 14-day randomized clinical trial of six-degree head-down tilt bedrest study in older adults aged 55–65 years old (BROA). Here we will describe the development of a multi-modality countermeasure protocol for the BROA campaign that includes upper- and lower-body resistance exercise and head-down tilt cycle ergometry (high-intensity interval and continuous aerobic exercise training). We provide reasoning for the choice of these modalities following review of the latest available information on exercise as a countermeasure for inactivity and spaceflight-related deconditioning. In summary, this paper sets out to review up-to-date exercise countermeasure research from spaceflight and head-down bedrest studies, whilst providing support for the proposed research countermeasure protocols developed for the bedrest study in older adults.

Effects of Multimodal Inpatient Rehabilitation vs Conventional Pulmonary Rehabilitation on Physical Recovery After Esophageal Cancer Surgery

ObjectiveTo determine the effects of multimodal rehabilitation initiated immediately after esophageal cancer surgery on physical recovery compared with conventional pulmonary rehabilitation. DesignRetrospective study. SettingPrivate quaternary care hospital. ParticipantsFifty-nine inpatients (N=59) who participated in either conventional pulmonary rehabilitation (n=30) or in multimodal rehabilitation (n=29) after esophageal cancer surgery were included. InterventionsBoth groups performed pulmonary exercises, including deep breathing, chest expansion, inspiratory muscle training, coughing, and manual vibration. In the conventional pulmonary rehabilitation group, light-intensity mat exercise, stretching, and walking were performed. The multimodal rehabilitation group performed resistance exercises and moderate- to high-intensity aerobic interval exercises using a bicycle. Main Outcome MeasuresThe European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire C30 (EORTC QLQ-C30), pain, 6-minute walk test (6MWT), 30-second chair stand test, and grip strengths were assessed before and after the rehabilitation programs. ResultsSymptom scales of pain, dyspnea, and insomnia in the EORTC QLQ-C30 as well as 6MWT improved significantly after each program (P<.05). 6MWT (73.1±52.6 vs 28.4±14.3, P<.001, d=1.15), 30-second chair stand test (3.5±3.9 vs 0.35±2.0, P<.001, d=1.06), and left grip strength (1.2±1.3 vs 0.0±1.5, P=.002, d=0.42) improved significantly in the multimodal rehabilitation group compared with the pulmonary rehabilitation group. While right grip strength also showed more improvement for those undergoing the multimodal program, the mean strength difference was not clinically meaningful. ConclusionsA multimodal inpatient rehabilitation program instituted early after esophageal cancer surgery improved endurance for walking more than conventional pulmonary rehabilitation as measured by the 6MWT and the 30-second chair stand test.

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.

No Change in Inhibitory Control or P3 Following Different High-Intensity Interval Exercise Modalities.

Acute aerobic high-intensity interval exercise (HIIE) has demonstrated positive effects on inhibitory control and P3 event-related potential (ERP) in young adults. However, the evidence is not well established regarding the effects of different HIIE modalities that incorporate aerobic-resistance training on these cognitive and neurocognitive outcomes. The purpose of this investigation was to examine the transient effects of HIIE-aerobic and HIIE-aerobic/resistance on P3 and Flanker task performance. Participants (n = 24; 18–25 years old) completed the Flanker task at two time points (30 min and 85 min) following 9 min of HIIE-aerobic (intermittent bouts of walking and running at 90% of maximal heart rate), HIIE-aerobic/resistance (intermittent bouts of walking and high-intensity calisthenics), and seated rest on three separate counterbalanced days. Results revealed no changes in Flanker performance (i.e., reaction time and response accuracy) or P3 (latency and mean amplitude) following either HIIE conditions compared to seated rest. Together, these data suggest inhibitory control and neuroelectric underpinnings are not affected by different modalities of HIIE at 30 min and 85 min post-exercise. Such findings reveal that engaging in short bouts of different HIIE modalities for overall health neither improves nor diminishes inhibitory control and brain function for an extended period throughout the day.

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.

From the Literature

From the Literature

Does group-based high-intensity aerobic interval training improve the inflammatory status in patients with chronic heart failure?

Chronic heart failure (CHF) is a multifaceted syndrome associated with endothelial dysfunction and increased inflammation. Despite the existing controversies regarding the appropriate training modality, it is widely accepted that supervised cardiac rehabilitation (CR) interventions lead to proinflammatory biomarkers reduction and cellular adhesion molecules in patients with CHF. The aim of the study was to quantify the effects of 12-week group-based high-intensity aerobic interval training (HIAIT)/modified group-based HIAIT intervention (m-Ullevaal) vs. moderate continuous training (MICT) on serum levels of proinflammatory biomarkers. Single-blind, two-arm, prospective randomized controlled trial conducted on CHF outpatients performing group-based CR interventions throughout a 12-week period. The setting of the study was the Medical Center of Outpatient Rehabilitation and Sports Medicine, Plovdiv, Bulgaria. The population included a total of 120 outpatients of both genders, mean age of 63.73±6.68 years, with stable CHF (NYHA classes II to IIIB, were randomly assigned to HIAIT/ m-Ullevaal (N.=60) or to MICT (N.=60) group. Functional exercise capacity (FEC) of the eligible subjects was evaluated through 6-minute walk test (6MWT) and peak oxygen uptake. Blood samples were drawn at baseline, after 12 weeks follow-up for analyses of C-reactive protein (CRP), tumor necrosis factor-α (TNFα) and cellular adhesion molecules (CAM). Significant decreases in the serum levels of CRP (P=0.029), TNF-α (P=0.036), and vascular cell adhesion molecule-1 (VCAM-1) (P=0.040), were observed after 48 training sessions in the group-based HIAIT/m-Ullevaal intervention, except for intercellular adhesion molecule-1 (ICAM-1), which was higher in the MICT (P=0.034). FEC was significantly inversely related to CRP (r=-0.72, P<0.05), and the levels of VCAM-1 (r=-0.68, P<0.05). Both group-based CR interventions (HIAIT/m-Ullevaal and MICT) significantly reduced the serum levels of CRP, TNF- α, ICAM-1 and VCAM in patients with CHF. However, selected proinflammatory biomarkers changes and CAMs favorably decreased in the group-based HIAIT/m-Ullevaal intervention. The responses on serum levels of proinflammatory biomarkers and CAMs are dependent upon the type, intensity, and CR intervention duration. The group-based high-intensity aerobic interval training reduces significantly the proinflammatory biomarkers and cellular adhesion molecules in patients with chronic heart failure.

Chronotropic Responses to Exercise and Recovery in Myocardial Infarction Patients Taking β-Blockers Following Aerobic High-Intensity Interval Training: AN INTERFARCT STUDY.

The objectives of this study were to compare the effects of two different high-intensity interval training (HIIT) programs (low-volume vs high-volume) on chronotropic responses during exercise and recovery, and to contrast the results of the HIIT groups together to only physical activity recommendations in post-myocardial infarction (MI) patients taking β-blockers. Resting heart rate (HRrest), peak HR (HRpeak), HR reserve (HRreserve = HRpeak-HRrest), HR recovery (HRR) as the difference between HRpeak and post-exercise HR, and chronotropic incompetence were assessed in 70 patients (58 ± 8 yr) following MI with a cardiopulmonary exercise test to peak exertion before and after a 16-wk exercise intervention period. All participants were randomized to either attention control (AC) (physical activity recommendations) or one of the two supervised HIIT groups (2 d/wk). After the intervention, no significant between-HIIT group differences were observed. The HRpeak increased (P < .05) in low- (Δ= 8 ± 18%) and high-volume HIIT (Δ= 6 ± 9%), with a small decrease in AC (Δ=- 2 ± 12%, P > .05) resulting in large differences (P < .05) between HIIT and AC. The HRreserve increased (P < .05) in high-volume HIIT. The HRR slightly increased (P < .05) in low-volume (5th min, Δ= 19 ± 31%) and high-volume HIIT (2nd min, Δ= 15 ± 29%, and 5th min, Δ= 19 ± 28%). These findings suggest that both low- and high-volume HIIT elicit similar improvements in chronotropic responses after MI, independent of β-blocker treatment. Supervised HIIT was more effective than giving physical activity recommendations alone. Low-volume HIIT is presented as a potent and time-efficient exercise strategy that could enhance the sympathovagal balance in this population.

500-P: Determinants of Exercise-Induced Increase in Insulin Sensitivity

Exercise training enhances insulin sensitivity (Si) in humans. However, it is to be determined which phenotypic and muscle molecular changes underwrite this change in Si. We sought to understand the mechanisms behind increased Si following 12 weeks of high intensity aerobicinterval (HIIT), resistance (RT), or combined (CT) exercise training in 30 young and 24 old humans. Measurements included Si estimated from a two-stage hyperinsulinemic-euglycemic clamp, and a host of independent variables including VO2 peak, muscle mitochondrial respiration, Liver FWF (Fat-Water-Fraction), visceral and subcutaneous fat, and gene expression from muscle biopsies. We performed a univariate and multivariate analysis of Si vs. phenotypic changes induced by training. After adjusting for age, sex and exercise group, VO2max was positively associated with an increase in Si from pre to post exercise (p=0.032). Interestingly, within the RT group alone, positive association between VO2max and Si (p=0.05) and negative association between liver FWF and Si (p=0.034) were observed. Within the HIIT group, there was a positive association between muscular strength and Si (p=0.04). Separate multivariate models assessed the effect of muscle gene expression changes on Si while adjusting for age, training type, response to training, VO2max, and mitochondrial function. Enrichment Analysis of genes associated with Si showed upregulation of genes in Branched-Chain Amino Acid (BCAA) and Lysine metabolism, although the latter was specifically upregulated with HIIT. Products of lysine metabolism, such as alpha-aminoadipic acid have been implicated in development of insulin resistance and BCAA are involved in signaling of insulin response. A strong positive association of Si with both BCAA (FDR 0) and lysine metabolism (FDR 0.008) following HIIT and a weaker correlation between Si and BCAA metabolism (FDR 0.002) following RT indicates the role of muscle AA metabolism as a common factor contributing to enhanced Si following exercise training. Disclosure A. Prabha kumar: None. S. Dasari: None. M. W. Pataky: None. J. Crook: None. C. T. Ball: None. K. Klaus: None. I. R. Lanza: None. M. M. Robinson: Stock/Shareholder; Self; GE Healthcare. K. Nair: None. Funding National Institutes of Health (R01AG09531)

High-intensity interval aerobic exercise training (HIAT) in occupational health

High-intensity interval aerobic exercise training (HIAT) in occupational health

High intensity exercise during breast cancer chemotherapy - effects on long-term myocardial damage and physical capacity - data from the OptiTrain RCT

BackgroundAdjuvant systemic breast cancer treatment improves disease specific outcomes, but also presents with cardiac toxicity. In this post-hoc exploratory analysis of the OptiTrain trial, the effects of exercise on cardiotoxicity were monitored by assessing fitness and biomarkers over the intervention and into survivorship.Methods; Women starting chemotherapy were randomized to 16-weeks of resistance and high-intensity interval training (RT-HIIT), moderate-intensity aerobic and high-intensity interval training (AT–HIIT), or usual care (UC). Outcome measures included plasma troponin-T (cTnT), Nt-pro-BNP and peak oxygen uptake (VO2peak), assessed at baseline, post-intervention, and at 1- and 2-years.ResultsFor this per-protocol analysis, 88 women met criteria for inclusion. Plasma cTnT increased in all groups post-intervention. At the 1-year follow-up, Nt-pro-BNP was lower in the exercise groups compared to UC. At 2-years there was a drop in VO2peak for patients with high cTnT and Nt-pro-BNP. Fewer patients in the RT-HIIT group fulfilled biomarker risk criteria compared to UC (OR 0.200; 95% CI = 0.055–0.734).ConclusionsIn this cohort, high-intensity exercise was associated with lower levels of NT-proBNP 1-year post-baseline, but not with cTnT directly after treatment completion. This may, together with the preserved VO2peak in patients with low levels of biomarkers, indicate a long-term cardioprotective effect of exercise.Trial registrationClinicaltrials.govNCT02522260, Registered 13th of august 2015 – Retrospectively RegisteredGraphical abstract

Effect of exercise intervention dosage on reducing visceral adipose tissue: a systematic review and network meta-analysis of randomized controlled trials.

Visceral adipose tissue (VAT) are deleterious fat deposits in the human body and can be effectively reduced by exercise intervention. Despite well-established exercise prescriptions are available, the effective dosage of exercise for reducing VAT requires verification. The aims of this systematic review and meta-analysis were to determine the most effective exercise dosage (modality, intensity, duration, and amount) for decreasing VAT. Nine databases (EMBASE, Medline, Cochrane Central Register of Controlled Trial, PubMed, CINAHL, Scopus, Web of Science, Airiti Library, and PerioPath) were systematically searched for randomized controlled trials that objectively assessed VAT. The arms of included studies covered with different exercise modalities and dosage. Relevant databases were searched through February 2020. Of the 34 studies (n = 1962) included in systematic review, 32 (n = 1900) were pooled for pairwise or network meta-analysis. The results indicated that high-intensity interval training (SMD -0.39, 95% CI -0.60 to -0.18) and aerobic exercise (SMD -0.26, 95% CI -0.38 to -0.13) of at least moderate intensity were beneficial for reducing VAT. By contrast, resistance exercise, aerobic exercise combined with resistance exercise, and sprint interval training had no significant effects. No difference in VAT reduction was observed between exercising more or less than 150 min per week. Meta-regression revealed that the effect of VAT reduction was not significantly influenced by an increase in the duration of or amount of exercise in an exercise program. The effective dosage of exercise for reducing VAT was three times per week for 12 to 16 weeks, while duration per session for aerobic exercise was 30-60 min, and either less than 30 min or 30-60 min of high-intensity interval training accomplished sufficient energy expenditure to impact VAT. These results can inform exercise prescriptions given to the general population for improving health by reducing VAT.