Efficacy of high-intensity interval and continuous endurance trainings on cecal microbiota metabolites and inflammatory factors in diabetic rats induced by high-fat diet.

Physical exercise is known to modulate the intestinal microbiota composition and control the symptoms of metabolic syndrome. In this research, we intend to investigate and compare the effect of high-intensity interval and continuous endurance trainings (HIIT and CET) on cecal microbiota metabolites and inflammatory factors in diabetic rats. A number of Wistar rats were made diabetic by a high-fat diet and trained under two types of exercise protocols, HIIT and CET. After taking samples from the cecal tissue and serum of rats to reveal the effect of exercise, three microbial species from the Firmicute and Bacteroid phyla, which are the main types of intestinal microbes, and their metabolites include two short-chain fatty acids (SCFAs), butyrate and propionate and also, the inflammatory factors TLR4 and IL6 were analyzed through quantitative polymerase chain reaction (qPCR), high-performance liquid chromatography (HPLC), and Enzyme-linked immunosorbent assay (ELISA) methods. In general, exercise while increasing the representative of Firmicute has caused a relative reduction of Bacteroides and improved the concentration of SCFAs. In this regard, HIIT outperforms CET in up-regulating Akkermansia and Butyrivibrio expression, and butyrate and propionate metabolites concentration. Also, both exercises significantly reduced cecal expression of TLR4 and sera concentration of IL6 compared to the diabetic group, although the reduction rate was higher in the CET group than in HIIT. Our findings suggest that some symptoms of metabolic syndrome such as intestinal dysbiosis and the resulting metabolic disorders are better controlled by HIIT and inflammation by CET. Certainly, more extensive research on other contributing factors could help clarify the results.

Phase 1 randomized trial of inpatient high-intensity interval training after major surgery.

BACKGROUND: High-intensity interval training (HIT) can provide physiologic benefits and may improve postoperative recovery but has not been evaluated in inpatients. This study aimed to evaluate the safety and tolerability of HIT after major surgery. METHODS: We performed a phase I randomized study comparing HIT with low-intensity continuous ambulation (40 m) during the initial inpatient stay after major surgery at a large academic center. Clinicopathologic and pre- and post-exercise physiologic data were captured. Perceived exertion was measured throughout the intervention. RESULTS: Twenty-two subjects were enrolled and randomized with 90% (20 subjects, 10 per arm) completing all aspects of the study. One patient declined participation in the exercise intervention. The HIT and continuous ambulation groups were relatively similar in terms of median age (65.5 vs 63.5), female sex (20% vs 40%), White race (90% vs 90%), having a cancer diagnosis (100% vs 80%), undergoing gastrointestinal surgery (60% vs 80%), median Karnofsky score (60 vs 60), and ability to independently ambulate preoperatively (100% vs 90%). All subjects completed the exercise without protocol deviation, cohort crossover, or safety events. Compared with the continuous ambulation group, the HIT group had higher end median perceived exertion (5.0 [IQR, 5.5] vs 3.0 [IQR, 1.8]), shorter overall time to complete assigned exercise (56.6 seconds vs 91.8 seconds), and a trend toward higher median gait speed over 40 m (0.71 m/s vs 0.44 m/s, P = .126). CONCLUSION: HIT in the hospitalized postoperative patient is safe and may be implemented to help promote positive physiologic outcomes and recovery.

Highlighting the effects of high-intensity interval training on the changes associated with hypertrophy, apoptosis, and histological proteins of the heart of old rats with type 2 diabetes.

T2DM is known to cause disturbances in glucose homeostasis and negative changes in the heart muscle, while aging and diabetes are recognized risk factors for CVD. Given this, our study aims to investigate a method for controlling and managing CVDs induced by T2DM in elderly populations. To achieve this, we categorized 40 rats into 5 groups, including HAD (n = 8), HA (n = 8), AD (n = 8), AHT (n = 8), and ADT (n = 8). The exercise protocol consisted of eight weeks of HIIT (three sessions per week) performed at 90-95% of maximal speed. Following cardiac tissue extraction, we assessed the levels of IGF-1, PI3K, and AKT proteins using Western blot technique, and analyzed the histopathological variations of the heart tissue using H&E, Sudan Black, and Masson's trichrome tissue staining. The histological findings from our study demonstrated that T2DM had a significant impact on the development of pathological hypertrophy and fibrosis in the heart tissue of elderly individuals. However, HIIT not only effectively controlled pathological hypertrophy and fibrosis, but also induced physiological hypertrophy in the AHT and ADT groups compared to the HA and AD groups. Results from Sudan Black staining indicated that there was an increase in lipid droplet accumulation in the cytoplasm of cardiomyocytes and their nuclei in the HA and AD groups, while the accumulation of lipid droplets decreased significantly in the AHT and ADT groups. In both the AHT group and the ADT group, a single HIIT session led to a reduction in collagen fiber accumulation and fibrotic frameworks. Our research also revealed that diabetes caused a significant elevation in the levels of IGF-1, PI3K, and AKT proteins, but after eight weeks of HIIT, the levels of these proteins decreased significantly in the training groups. Overall, our findings suggest that HIIT may be a suitable non-pharmacological approach for improving histological and physiological changes in elderly individuals with T2DM. However, we recommend further research to examine the impact of HIIT training on both healthy and diseased elderly populations.

The Combined Effects of High-Intensity Interval Exercise Training and Dietary Supplementation on Reduction of Body Fat in Adults with Overweight and Obesity: A Systematic Review.

Excessive body fat is associated with various comorbidities including cardiovascular disease, type 2 diabetes mellitus and certain types of cancer. The search for effective, relatively easy to maintain body-fat reduction interventions has been ongoing. We aimed to review the current literature to assess the effectiveness of high-intensity interval training with and without dietary supplementation on body fat loss, concentration of markers of metabolic health and aerobic capacity of adults with overweight and obesity. Seventy full-text articles were assessed to determine their eligibility and thirteen were included in the review. The methodology of this systematic review was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Almost all studies (93%) demonstrated effectiveness of high-intensity interval training of various protocols in reducing body fat, improving metabolic health and aerobic capacity of adults with overweight and obesity. These effects were enhanced by an addition of a dietary supplement, such as green tea or ginger or other. Although combining HIIT with dietary supplementation seem to improve body composition, metabolic health and aerobic capacity in adults with overweight and obesity in some instances to a greater extent than HIIT alone, it does not seem to be necessary to combine these two interventions.

Cardiorespiratory Fitness and Performance Adaptations to High-Intensity Interval Training: Are There Differences Between Men and Women? A Systematic Review with Meta-Analyses.

BACKGROUND: It is important to consider biological sex as a variable that might influence exercise adaptation in order to optimize exercise prescription for men and women. OBJECTIVE: The aim of this study was to quantify the impact of biological sex on maximal oxygen uptake ([Formula: see text]O2max) and performance outcomes after high-intensity interval training (HIIT). METHODS: A systematic search and review was conducted by two independent reviewers up to 8 September 2022 using MEDLINE, SPORTDiscus, and Sports Medicine & Education Index in ProQuest. Trials including healthy adults were included if they presented data for or compared male and female [Formula: see text]O2max or performance outcomes in response to HIIT. Performance outcomes included measures of exercise performance and concurrently measured physiological adaptations. Where appropriate, a random-effects, pre-post meta-analysis was undertaken. Data were sub-grouped for men and women, baseline training level, mean age, intervention type, and intervention length. Heterogeneity was assessed using Chi2, Cochran's Q, and Higgins I2 and sensitivity analyses, where required. Study quality was assessed using the Newcastle-Ottawa Scale and publication bias was assessed through visual inspection of funnel plots. RESULTS: Thirty-three references from 28 trials were included in the review (n = 965; 462 women and 503 men). Meta-analyses included 19 studies for [Formula: see text]O2max, eight for peak power output from [Formula: see text]O2max testing (PPO), and five for threshold power (powerAT). Meta-analyses revealed similar increases in [Formula: see text]O2max in women (g = 0.57; 95% CI 0.44-0.69) and men (g = 0.57; 95% CI 0.42-0.72), and powerAT in women (g = 0.38; 95% CI 0.13-0.64) and men (g = 0.38; 95% CI 0.11-0.64). Raw mean differences for change in [Formula: see text]O2max were Δ 0.32 L·min-1 and 3.50 mL·kg-1·min-1 in men, versus Δ 0.20 L·min-1 and 3.34 mL·kg-1·min-1 for women. No significant sex differences were present for the primary analysis of any outcome. After sub-grouping, significant differences were present for PPO where the effect size was higher for well-trained women (g = 0.37) compared with well-trained men (g = 0.17), and for [Formula: see text]O2max where interventions with a duration of 4 weeks or less had significantly smaller effect sizes compared with those longer than 4 weeks (p < 0.001). Unweighted mean percentage change in [Formula: see text]O2max, PPO, and powerAT across studies was 11.16 ± 7.39%, 11.16 ± 5.99%, and 8.07 ± 6.55% for women, and 10.90 ± 5.75%, 8.22 ± 5.09%, and 7.09 ± 7.17% for men, respectively. Significant heterogeneity was present for both [Formula: see text]O2max and PPO (I2, range: 62.06-78.80%). Sub-grouping by baseline training status and intervention length decreased heterogeneity in most groups. A qualitative synthesis of other outcomes indicated similar improvements in fitness and performance for men and women with some evidence suggesting differences in the mechanisms of adaptation. LIMITATIONS AND RISK OF BIAS: Publication bias is unlikely to have significantly influenced results for [Formula: see text]O2max or powerAT, but the meta-analysis of PPO could have benefitted from additional study data to strengthen results. The overlap in age categories and sensitivity of the analysis limits the accuracy of the results of the sub-grouping by age. CONCLUSIONS: Findings indicated no sex-specific differences for any fitness or performance outcomes. Baseline training status and intervention length accounted for most variability in outcomes. PROSPERO registration number: CRD42021272615.

Intense interval exercise induces greater changes in post-exercise metabolism compared to submaximal exercise in middle-aged adults.

INTRODUCTION: High-intensity interval training (HIIT) and sprint interval training (SIT) consistently elevate post-exercise metabolism compared to moderate-intensity continuous training (MICT) in young adults (18-25 years), however few studies have investigated this in middle-aged adults. PURPOSE: To assess the effect of exercise intensity on post-exercise metabolism following submaximal, near-maximal, and supramaximal exercise protocols in middle-aged adults. METHODS: 12 participants (8 females; age: 44 ± 10 years; V ˙ O2max: 35.73 ± 9.97 mL·kg-1 min-1) had their oxygen consumption ( V ˙ O2) measured during and for 2 h following 4 experimental sessions: (1) no-exercise control (CTRL); (2) MICT exercise (30 min at 65% V ˙ O2max); (3) HIIT exercise (10 × 1 min at 90% maximum heart rate with 1 min rest); and (4) modified-SIT exercise (8 × 15 s "all-out" efforts with 2 min rest). Between session differences for V ˙ O2 and fat oxidation were compared. RESULTS: O2 consumed post-exercise was elevated during the 1st h and 2nd h following HIIT (15.9 ± 2.6, 14.7 ± 2.3 L; P < 0.036, d > 0.98) and modified-SIT exercise (16.9 ± 3.3, 15.30 ± 3.4 L; P < 0.041, d > 0.96) compared to CTRL (13.3 ± 1.9, 12.0 ± 2.5 L) while modified-SIT was also elevated vs HIIT in the 1st h (P < 0.041, d > 0.96). Total post-exercise O2 consumption was elevated following all exercise sessions (MICT: 27.7 ± 4.1, HIIT: 30.6 ± 4.8, SIT: 32.2 ± 6.6 L; P < 0.027, d > 1.03) compared to CTRL (24.9 ± 4.1 L). Modified-SIT exercise increased fat oxidation (0.103 ± 0.019 g min-1) compared to all sessions post-exercise (CTRL: 0.059 ± 0.025, MICT: 0.075 ± 0.022, HIIT: 0.081 ± 0.021 g·min-1; P < 0.007, d > 1.30) and HIIT exercise increased compared to CTRL (P = 0.046, d = 0.87). CONCLUSION: Exercise intensity has an important effect on post-exercise metabolism in middle-aged adults.

Physiological and psychological outcomes of high intensity interval training in patients with heart failure compared to moderate continuous training and usual care: A systematic review with meta analysis.

BACKGROUND: An important component of secondary prevention of CVD (including HF) is comprehensive cardiac rehab, including exercise. Novel, individualised approaches are needed to increase uptake and adherence to exercise programmes, one area offering potential is HIIT. HIIT has been shown to be both safe and effective for improving cardiovascular fitness in both coronary artery disease and HF patients. OBJECTIVES: To provide a current and up to date evaluation of the physiological and psychological outcomes of HIIT in patients with HF compared to MCT and UC. Secondly to perform sub-group analyses comparing short and long HIIT protocols. METHODS: A systematic review and meta-analysis of randomised controlled trials was undertaken. Medline, Embase, Scopus, CINAHL and SportDISCUS were searched up to July 2022. Trials were included if they carried out a HIIT intervention (defined at intensity ≥ 80% peak HR or ≥ 80% VO2peak) in HF patients (HFpEF or HFrEF) for at least 6 weeks. Comparator group was UC or MCT. RESULTS: HIIT was shown to be superior to MCT and UC for improving VO2peak (HIIT mean improvement 3.1 mL.kg-1min-1). HITT was superior to MCT and UC for improving LVEF (HIIT mean improvement 5.7%). HIIT was superior to MCT and UC for improving HRQoL, using the MLHFQ (HIIT mean point change of -12.8). Subgroup analysis showed no difference between long and short HIIT. CONCLUSION: HIIT improves VO2peak, LVEF and HRQoL in patients with HF, the improvements seen in VO2peak and LVEF are superior in HIIT compared to MCT and UC.

Effects of high-intensity interval training on functional performance and maximal oxygen uptake in comparison with moderate intensity continuous training in cancer patients: a systematic review and meta-analysis.

INTRODUCTION: High-intensity interval training (HIIT) is an appropriate training modality to improve endurance and therefore contributes to physical performance. This review investigates the effect of HIIT on functional performance in cancer patients. We reviewed the relative peak oxygen uptake (relV̇O2PEAK) and meta-analytical compared HIIT with moderate intensity continuous training (MICT). Furthermore, we took various training parameters under consideration. METHODS: A systematic literature search was conducted in Scopus, PubMed, and Cochrane Library databases. For the review, we included randomized controlled trials containing HIIT with cancer patients. From this, we filtered interventions with additional MICT for the meta-analysis. Outcomes of interest were various functional performance assessments and V̇O2MAX. RESULTS: The research yielded 584 records which fit the inclusion criteria, of which 31 studies with n=1555 patients (57.4±8.6 years) could be included in the overall review and 8 studies in the meta-analysis (n=268, 59.11±5.11 years) regarding relV̇O2PEAK. Different functional outcomes were found, of which walking distance (+8.63±6.91% meters in 6-min walk test) and mobility (+2.7cm in sit and reach test) improved significantly due to HIIT. In terms of relV̇O2PEAK, the performance of cancer patients was improved by HIIT (10.68±6.48%) and MICT (7.4±4.29%). HIIT can be favored to increase relV̇O2PEAK (SMD 0.37; 95% CI 0.09-0.65; I2=0%; p=0.009). Effect sizes for relV̇O2PEAK improvements correlate moderately with total training volume (Spearman's ρ=0.49; p=0.03), whereas percentage increases do not (Spearman's ρ=0.24; p=0.14). CONCLUSION: Functional and physical outcomes were positively altered by different HIIT protocols and forms of implementation, whereas a tendency toward more effectiveness of HIIT vs. MICT was found for relV̇O2PEAK. Future studies should include functional parameters more often, to finally allow a comparison between both training protocols in this regard.

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

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-ß (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.

Effects of Exercise on Physical Function and Quality of Life in Prostate Cancer Patients Receiving Androgen Deprivation Therapy: High-Intensity Interval Training versus Moderate-Intensity Continuous Training.

INTRODUCTION: We assessed the effects of exercise on the physical function and health quality of life (hQoL) in prostate cancer patients underwent androgen deprivation therapy (ADT). Additionally, the effects of high-intensity interval training (HIIT) on the physical function and hQoL in these patients were compared with those of moderate-intensity continuous training (MICT). METHODS: Seventeen prostate cancer patients who underwent ADT were prospectively allocated to either HIIT (n = 9) or MICT (n = 8). In these patients, physical function and hQoL were measured before and after 12 weeks of exercise and 3-6 months after the exercise program, respectively. RESULTS: Although the whole-body total mass significantly increased after the exercise program, it was equivalent regardless of the exercise methods. After the exercise program, muscle strength and endurance improved and tended to be maintained until 3-6 months later. Improvement in muscle endurance was more prominent after HIIT, and that in muscle strength was more prominent after MICT. Performance in the senior fitness test improved after the exercise program, and HIIT was more effective for lower and upper muscle endurance and flexibility, although MICT was more effective for the others. The hQoL significantly improved 3-6 months after the exercise program. CONCLUSION: The 12-week exercise program has a positive effect on the physical function and hQoL in prostate cancer patients who underwent ADT. In these patients, compared with MICT, HIIT may be a better option for improving muscle endurance, which is thought to be significant for preventing falls and fractures in elderly patients.

High-Intensity Interval Training and Cardiometabolic Health in the General Population: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

BACKGROUND: High-intensity interval training (HIIT) remains a promising exercise mode in managing cardiometabolic health. Large-scale analyses are necessary to understand its magnitude of effect on important cardiometabolic risk factors and inform guideline recommendations. OBJECTIVE: We aimed to perform a novel large-scale meta-analysis on the effects of HIIT on cardiometabolic health in the general population. METHODS: PubMed (MEDLINE), the Cochrane library and Web of Science were systematically searched. Randomised controlled trials (RCTs) published between 1990 and March 2023 were eligible. Research trials reporting the effects of a HIIT intervention on at least one cardiometabolic health parameter with a non-intervention control group were considered. RESULTS: This meta-analysis included 97 RCTs with a pooled sample size of 3399 participants. HIIT produced significant improvements in 14 clinically relevant cardiometabolic health parameters, including peak aerobic capacity (VO2) [weighted mean difference (WMD): 3.895 ml min-1 kg-1, P < 0.001), left ventricular ejection fraction (WMD: 3.505%, P < 0.001), systolic (WMD: - 3.203 mmHg, P < 0.001) and diastolic (WMD: - 2.409 mmHg, P < 0.001) blood pressure, resting heart rate (WMD: - 3.902 bpm, P < 0.001) and stroke volume (WMD: 9.516 mL, P < 0.001). Body composition also significantly improved through reductions in body mass index (WMD: - 0.565 kg m-2, P < 0.001), waist circumference (WMD: - 2.843 cm, P < 0.001) and percentage body fat (WMD: - 0.972%, P < 0.001). Furthermore, there were significant reductions in fasting insulin (WMD: - 13.684 pmol L-1, P = 0.004), high-sensitivity C-reactive protein (WMD: - 0.445 mg dL-1, P = 0.043), triglycerides (WMD: - 0.090 mmol L-1, P = 0.011) and low-density lipoprotein (WMD: - 0.063 mmol L-1, P = 0.050), concurrent to a significant increase in high-density lipoprotein (WMD: 0.036 mmol L-1, P = 0.046). CONCLUSION: These results provide further support for HIIT in the clinical management of important cardiometabolic health risk factors, which may have implications for physical activity guideline recommendations.

Effectiveness of supplementation with date seed (Phoenix dactylifera) as a functional food on inflammatory markers, muscle damage, and BDNF following high-intensity interval training: a randomized, double-blind, placebo-controlled trial.

PURPOSE: High-intensity interval training (HIIT) is one of the most effective protocols, even though acute HIIT causes inflammatory and oxidative damage. The aim of this study was to examine the effect of date seeds powder (DSP) during HIIT sessions on inflammation markers, oxidants and antioxidants, brain-derived neurotrophic factor (BDNF), exercise-induced muscle damage, and body composition. MATERIAL AND METHODS: Thirty-six recreational runners (men and women), aged 18-35 years, were randomly assigned to consume 26 g/day of DSP or wheat bran powder during HIIT workouts for a period of 14 days. At baseline, at the end of the intervention, and 24 h after the intervention, blood samples were obtained to determine inflammatory, oxidant/antioxidant, and muscle damage markers, as well as BDNF. RESULTS: DSP supplementation resulted in a significant downward trend in high-sensitivity C-reactive protein (Psupplement × time = 0.036), tumor necrosis factor alpha (Psupplement × time = 0.010), interleukin-6 (Psupplement × time = 0.047), malondialdehyde (Psupplement × time = 0.046), creatine kinase (Psupplement × time = 0.045), and lactate dehydrogenase (Psupplement × time = 0.040) after the intervention, as well as a significant increase in total antioxidant capacity (Psupplement × time ≤ 0.001). However, interleukin-10 (Psupplement × time = 0.523), interleukin-6/interleukin-10 (Psupplement × time = 0.061), BDNF (Psupplement × time = 0.160), and myoglobin (Psupplement × time = 0.095) levels did not change significantly in comparison to the placebo group. Moreover, analysis demonstrated that DSP supplementation over 2 weeks had no significant effect on body composition. CONCLUSION: During the 2 weeks of the HIIT protocol, the consumption of date seed powder by participants who had engaged in moderate or high physical activity alleviated inflammation and muscle damage. ETHICS AND DISSEMINATION: This study was approved by the Medical Ethics Committee of TBZMED (No.IR.TBZMED.REC.1399.1011). TRIAL REGISTRATION: Iranian Registry of Clinical Trials website ( www.IRCt.ir/ , IRCT20150205020965N9).

Exercise training reduces circulating cytokines in male patients with coronary artery disease and type 2 diabetes: A pilot study.

Low-grade inflammation is central to coronary artery disease (CAD) and type 2 diabetes (T2D) and is reduced by exercise training. The objective of this study was to compare the anti-inflammatory potential of moderate-to-vigorous intensity continuous training (MICT) and high-intensity interval training (HIIT) in patients with CAD with or without T2D. The design and setting of this study is based on a secondary analysis of registered randomized clinical trial NCT02765568. Male patients with CAD were randomly assigned to either MICT or HIIT, with subgroups divided according to T2D status (non-T2D-HIIT n = 14 and non-T2D-MICT n = 13; T2D-HIIT n = 6 and T2D-MICT n = 5). The intervention was a 12-week cardiovascular rehabilitation program consisting of either MICT or HIIT (twice weekly sessions) and circulating cytokines measured pre- and post-training as inflammatory markers. The co-occurrence of CAD and T2D was associated with increased plasma IL-8 (p = 0.0331). There was an interaction between T2D and the effect of the training interventions on plasma FGF21 (p = 0.0368) and IL-6 (p = 0.0385), which were further reduced in the T2D groups. An interaction between T2D, training modalities, and the effect of time (p = 0.0415) was detected for SPARC, with HIIT increasing circulating concentrations in the control group, while lowering them in the T2D group, and the inverse occurring with MICT. The interventions also reduced plasma FGF21 (p = 0.0030), IL-6 (p = 0.0101), IL-8 (p = 0.0087), IL-10 (p < 0.0001), and IL-18 (p = 0.0009) irrespective of training modality or T2D status. HIIT and MICT resulted in similar reductions in circulating cytokines known to be increased in the context of low-grade inflammation in CAD patients, an effect more pronounced in patients with T2D for FGF21 and IL-6.

Conventional methods to prescribe exercise intensity are ineffective for exhaustive interval training.

PURPOSE: To compare methods of relative intensity prescription for their ability to normalise performance (i.e., time to exhaustion), physiological, and perceptual responses to high-intensity interval training (HIIT) between individuals. METHODS: Sixteen male and two female cyclists (age: 38 ± 11 years, height: 177 ± 7 cm, body mass: 71.6 ± 7.9 kg, maximal oxygen uptake ([Formula: see text]O2max): 54.3 ± 8.9 ml·kg-1 min-1) initially undertook an incremental test to exhaustion, a 3 min all-out test, and a 20 min time-trial to determine prescription benchmarks. Then, four HIIT sessions (4 min on, 2 min off) were each performed to exhaustion at: the work rate associated with the gas exchange threshold ([Formula: see text]GET) plus 70% of the difference between [Formula: see text]GET and the work rate associated with [Formula: see text]O2max; 85% of the maximal work rate of the incremental test (85%[Formula: see text]max); 120% of the mean work rate of the 20 min time-trial (120%TT); and the work rate predicted to expend, in 4 min, 80% of the work capacity above critical power. Acute HIIT responses were modelled with participant as a random effect to provide estimates of inter-individual variability. RESULTS: For all dependent variables, the magnitude of inter-individual variability was high, and confidence intervals overlapped substantially, indicating that the relative intensity normalisation methods were similarly poor. Inter-individual coefficients of variation for time to exhaustion varied from 44.2% (85%[Formula: see text]max) to 59.1% (120%TT), making it difficult to predict acute HIIT responses for an individual. CONCLUSION: The present study suggests that the methods of intensity prescription investigated do not normalise acute responses to HIIT between individuals.

Efficacy of high-intensity interval training for improving mental health and health-related quality of life in women with polycystic ovary syndrome.

Women with PCOS have substantially greater symptoms of depression and anxiety, and a lower health-related quality of life (HRQoL) compared to women without PCOS. The aim of this study was to determine if high-intensity interval training (HIIT) could provide greater improvements in mental health outcomes than standard moderate-intensity continuous training (MICT). Twenty-nine overweight women with PCOS aged 18-45 years were randomly assigned to 12 weeks of either MICT (60-75% HRpeak, N = 15) or HIIT (> 90% HRpeak, N = 14). Outcome measures included symptoms of depression, anxiety and stress (DASS-21), general HRQoL (SF-36) and PCOS specific HRQoL (PCOSQ) collected at baseline and post-intervention. Reductions in depression (Δ - 1.7, P = 0.005), anxiety (Δ - 3.4, P < 0.001) and stress (Δ - 2.4, P = 0.003) scores were observed in the HIIT group, while MICT only resulted in a reduction in stress scores (Δ - 2.9, P = 0.001). Reductions in anxiety scores were significantly higher in the HIIT group compared to the MICT group (ß = - 2.24, P = 0.020). Both HIIT and MICT significantly improved multiple domain scores from the SF-36 and PCOSQ. This study highlights the potential of HIIT for improving mental health and HRQoL in overweight women with PCOS. HIIT may be a viable strategy to reduce symptoms of depression and anxiety in women with PCOS, however, large-scale studies are required to confirm these findings.Trial registration number: ACTRN12615000242527.

A Meta-Analysis of the Influence on Inflammatory Factors in Type 2 Diabetes among Middle-Aged and Elderly Patients by Various Exercise Modalities.

The purpose of this study was to investigate the effects of various exercise modalities on inflammatory factors in middle-aged and elderly patients with type 2 diabetes (MEPT2D), as lifestyle changes, such as physical activity and dietary modifications, are considered important in the prevention of type 2 diabetes. For the study methodology, Pubmed, CNKI, EBSCO, Wanfang Data, and Web of Science were selected for the search. The methodological quality of the included studies was assessed by the Cochrane Risk of Bias (ROB) tool, and statistically analyzed using the RevMan 5.4.1 analysis software, which included 18 investigations involving 853 study subjects. Meta-analysis findings indicated that aerobic training (AT), resistance training (RT), combined training (CT), and high-intensity interval training (HIIT) showed significant reductions in CRP, TNF-α, IL-6, and IL-10 levels in MEPT2D. Among them, HIIT was superior to other training modalities in reducing TNF-α levels, while CT was superior to AT, RT, and HIIT in decreasing IL-6, IL-10, and CRP in MEPT2D. Meanwhile, RT had limited effects in reducing CRP and TNF-α levels in MEPT2D. However, HIIT had no significant effect on IL-6 and IL-10 in MEPT2D. In conclusion, long-term regular AT, RT, CT, and HIIT all contributed to the reduction of inflammatory status (CRP, TNF-α, IL-6, and IL-10) in MEPT2D, while CT (for CRP, IL-6, and IL-10) and HIIT (for TNF-α) represent the best approaches to counteract the inflammatory response in MEPT2D.

High-intensity interval training in children and adolescents with special educational needs: a systematic review and narrative synthesis.

BACKGROUND: High-intensity interval training (HIIT) has been promoted as a time-efficient exercise strategy to improve health and fitness in children and adolescents. However, there remains little consensus in the literature regarding its efficacy in children and adolescents with special educational needs (SEN). This study aimed to examine HIIT as a means of improving key health and fitness parameters in children and adolescents with SEN. METHODS: A systematic search was conducted on eight databases (MEDLINE, Embase, SPORTDiscus, Web of Science, Scopus, PsycINFO, CINAHL, and Cochrane Library). Studies were eligible if they 1) included an HIIT protocol, 2) examined parameters related to both physical and mental aspects of health and fitness, and 3) examined children and adolescents with SEN aged 5-17 years. RESULTS: Of the 1727 studies yielded by the database search, 13 (453 participants) were included and reviewed. We found that HIIT generally improved body composition, physical fitness, and cardiometabolic risk biomarkers across a spectrum of SEN (e.g., attention deficit hyperactivity disorder, cerebral palsy, developmental coordination disorder, and mental illness). Improvements in mental health and cognitive performance following HIIT have also been observed. CONCLUSION: This review provides up-to-date evidence for HIIT as a viable exercise strategy for children and adolescents with SEN. Further research investigating the benefits of HIIT in a wider range of SEN populations is warranted. TRIAL REGISTRATION: This study was registered in the International Prospective Register of Systematic Review (PROSPERO; registration number CRD42022352696).

High intensity interval training is superior to moderate intensity continuous training in enhancing the anti-inflammatory and apoptotic effect of pentoxifylline in the rat model of endometriosis.

This study investigated the effects of pentoxifylline (PTX), high intensity interval training (HIIT) and moderate intensity continuous training (MICT) separately and in combination, on inflammatory and apoptotic pathways in the rat model of induced endometriosis. Endometriosis was induced through surgery on female Sprague-Dawley rats. Six weeks after the first surgery, the second look laparotomy was performed. After induction of endometriosis in rats, they were divided into control, MICT, PTX, MICT+ PTX, HIIT, HIIT+PTX groups. Two weeks after the second look laparotomy, PTX and exercise training interventions were performed for eight weeks. Endometriosis lesions were assessed histologically. Proteins content of the NF-κB, PCNA and Bcl-2 were measured by immunoblotting and genes expression of the TNF-α and VEGF were measured by Real-time PCR methods. Findings of the study indicated that, PTX significantly decreased volume and histological grading of lesions, proteins of NF-κB and Bcl-2; and genes expression of the TNF-α, and VEGF in lesions. HIIT significantly decreased volume and histological grading of lesions, NF-κB, TNF-α and VEGF in lesions. MICT did not induce any significant effect on the study variables. Although, MICT+PTX decreased significantly volume and histological grading of lesions, as well as NF-κB, and Bcl-2 in lesions, however, these factors were not significantly different with the PTX group. HIIT+PTX decreased significantly all of the study variables compared to other interventions, except for VEGF when compared to PTX. In summary, combination of PTX and HIIT can induce enhancing effect on suppression of endometriosis through suppressing inflammation, angiogenesis, and proliferation and enhancing apoptosis.

Cardiac rehabilitation in coronary artery bypass grafting patients: Effect of eight weeks of moderate-intensity continuous training versus high-intensity interval training.

BACKGROUND: Physical training in patients with heart failure can affect hemodynamic, cardiac and angiogenesis parameters. OBJECTIVE: The aim of the present study was to investigate the effects of traditional moderate-intensity rehabilitation training and interval training on some angiogenesis factors in coronary artery bypass graft (CABG) patients. METHODS: Thirty CABG patients (mean age±SD, 55±3 years) were randomly assigned to one of three groups: high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT) or the control group. After the initial assessments, eligible patients in the experimental groups (HIIT and MICT) performed exercise training for 8 weeks, while the control group did not. Angiogenesis and angiostatic indices, including pro-adrenomedullin (pro-ADM), basic fibroblast growth factor (bFGF), and endostatin, were then measured. RESULTS: The results showed no significant difference between pro-ADM in the HIIT and MICT groups (P = 0.99), but a significant difference was found between MICT and the control group and between HIIT and the control group (P = 0.001). There is also no significant difference between the bFGF levels in the HIIT and MICT training groups (P = 1.00), but the changes in this factor between the training groups and the control group were significant (P = 0.001). There was a significant difference between the levels of endostatin in all three groups. CONCLUSIONS: Two methods of cardiac rehabilitation (HIIT and MICT) may be useful for the recovery of patients with coronary artery bypass grafting. This improvement manifested itself in changes in angiogenesis and angiostatic indices in this study. However, more extensive studies are needed to investigate the effects of these two types of rehabilitation programs on other indicators of angiogenesis and angiostatic.