Effect of low-volume combined aerobic and resistance high-intensity interval training on vascular health in people with type 2 diabetes: a randomised controlled trial.

PURPOSE: We compared the effects of low-volume combined aerobic and resistance high-intensity interval training (C-HIIT), combined moderate-intensity continuous training (C-MICT) and waitlist control (CON) on vascular health after 8-weeks of supervised training, and an additional 10-months of self-directed training, in adults with type 2 diabetes (T2D). METHODS: Sixty-nine low active adults with T2D were randomised to 8-weeks of supervised C-HIIT (3 times/week, 78-min/week), C-MICT (current exercise guidelines, 4 times/week, 210-min/week) or CON. CON underwent usual care for 8-weeks before being re-randomised to C-HIIT or C-MICT. This was followed by 10-months of self-directed training for participants in C-HIIT and C-MICT. Vascular outcomes were evaluated at baseline, 8-weeks, and 12-months. RESULTS: After 8-weeks, supervised C-HIIT significantly improved relative flow-mediated dilation (FMD) compared with CON (mean difference [MD] 0.8% [0.1, 1.4], p = 0.025). Although not significantly different from CON, the magnitude of change in relative FMD following 8-weeks of supervised C-MICT was similar (MD 0.8% [-0.1, 1.7], p = 0.080). There were no differences in haemodynamic indices, carotid-femoral pulse wave velocity (cfPWV), or aortic reservoir pressure between groups at 8-weeks. After 12-months, there was a significant reduction in haemodynamic indices (time effect, p < 0.05) for both C-HIIT and C-MICT, with no between-group difference. The reduction in cfPWV over 12-months was significantly greater in C-MICT than C-HIIT (group × time effect, p = 0.018). There was no difference in FMD over time or between groups at 12-months. CONCLUSIONS: Short-term supervised C-HIIT and C-MICT both increased brachial artery FMD compared with CON. Long-term C-HIIT and C-MICT were beneficial for improving haemodynamic indices, but not brachial artery FMD. C-MICT was superior to C-HIIT for improving cfPWV at 12-months. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Identifier ACTRN12615000475549.

Clinical effectiveness of cardiac rehabilitation and barriers to completion in patients of low socioeconomic status in rural areas: A mixed-methods study.

OBJECTIVE: To investigate cardiac rehabilitation utilisation and effectiveness, factors, needs and barriers associated with non-completion. DESIGN: We used the mixed-methods design with concurrent triangulation of a retrospective cohort and a qualitative study. SETTING: Economically disadvantaged areas in rural Australia. PARTICIPANTS: Patients (≥18 years) referred to cardiac rehabilitation through a central referral system and living in rural areas of low socioeconomic status. MAIN MEASURES: A Cox survival model balanced by inverse probability weighting was used to assess the association between cardiac rehabilitation utilization and 12-month mortality/cardiovascular readmissions. Associations with non-completion were tested by logistic regression. Barriers and needs to cardiac rehabilitation completion were investigated through a thematic analysis of semi-structured interviews and focus groups (n = 28). RESULTS: Among 16,159 eligible separations, 44.3% were referred, and 11.2% completed cardiac rehabilitation. Completing programme (HR 0.65; 95%CI 0.57-0.74; p < 0.001) led to a lower risk of cardiovascular readmission/death. Living alone (OR 1.38; 95%CI 1.00-1.89; p = 0.048), having diabetes (OR 1.48; 95%CI 1.02-2.13; p = 0.037), or having depression (OR 1.54; 95%CI 1.14-2.08; p = 0.005), were associated with a higher risk of non-completion whereas enrolment in a telehealth programme was associated with a lower risk of non-completion (OR 0.26; 95%CI 0.18-0.38; p < 0.001). Themes related to logistic issues, social support, transition of care challenges, lack of care integration, and of person-centeredness emerged as barriers to completion. CONCLUSIONS: Cardiac rehabilitation completion was low but effective in reducing mortality/cardiovascular readmissions. Understanding and addressing barriers and needs through mixed methods can help tailor cardiac rehabilitation programmes to vulnerable populations and improve completion and outcomes.

Clinical Effectiveness and Utilisation of Cardiac Rehabilitation After Hospital Discharge: Data Linkage Analysis of 84,064 Eligible Discharged Patients (2016-2021).

BACKGROUND: Despite the highest levels of evidence on cardiac rehabilitation (CR) effectiveness, its translation into practice is compromised by low participation. AIM: This study aimed to investigate CR utilisation and effectiveness in South Australia. METHODS: This retrospective cohort study used data linkage of clinical and administrative databases from 2016 to 2021 to assess the association between CR utilisation (no CR received, commenced without completing, or completed) and the composite primary outcome (mortality/cardiovascular re-admissions within 12 months after discharge). Cox survival models were adjusted for sociodemographic and clinical data and applied to a population balanced by inverse probability weighting. Associations with non-completion were assessed by logistic regression. RESULTS: Among 84,064 eligible participants, 74,189 did not receive CR, with 26,833 of the 84,064 (31.9%) participants referred. Of these, 9,875 (36.8%) commenced CR, and 7,681 of the 9,875 (77.8%) completed CR. Median waiting time from discharge to commencement was 40 days (interquartile range, 23-79 days). Female sex (odds ratio [OR] 1.12; 95% CI 1.01-1.24; p=0.024), depression (OR 1.17; 95% CI 1.05-1.30; p=0.002), and waiting time >28 days (OR 1.15; 95% CI 1.05-1.26; p=0.005) were associated with higher odds of non-completion, whereas enrolment in a telehealth program (OR 0.35; 95% CI 0.31-0.40; p<0.001) was associated with lower odds of non-completion. Completing CR (hazard ratio [HR] 0.62; 95% CI 0.58-0.66; p<0.001) was associated with a lower risk of 12-month mortality/cardiovascular re-admissions. Commencing without completing was also associated with decreased risk (HR 0.81; 95% CI 0.73-0.90; p<0.001), but the effect was lower than for those completing CR (p<0.001). CONCLUSIONS: Cardiac rehabilitation (CR) attendance is associated with lower all-cause mortality/cardiovascular re-admissions, with CR completion leading to additional benefits. Quality improvement initiatives should include promoting referral, women's participation, access to telehealth, and reduction of waiting times to increase completion.

The impact of individualised versus standardised endurance and resistance training on the fitness-fatness index in inactive adults.

OBJECTIVES: The aim of the current study was to investigate the impact of individualised versus standardised combined endurance and resistance training on the fitness-fatness index in physically inactive adults. DESIGN: Randomised controlled trial. METHODS: Fifty-four participants aged 21-55 years were randomised into three groups; 1) non-exercise control (n = 18), 2) standardised moderate-intensity continuous training (n = 18), or 3) individualised moderate-intensity continuous training + high-intensity interval training (n = 18). The fitness-fatness index was calculated by dividing cardiorespiratory fitness (expressed as metabolic equivalents) by the waist-to-height ratio. Participants were classified as likely responders to the intervention if a change of ≥1 fitness-fatness index unit was achieved. RESULTS: The individualised group showed the greatest fitness-fatness index improvement (between group difference p < 0.001), with 100 % of this group classified as likely responders, compared to the standardised (68 %) and non-exercise control (0 %) groups. CONCLUSIONS: An individualised, threshold-based exercise programme may produce more favourable changes in the fitness-fatness index than a standardised exercise programme.

Effectiveness of cardiac rehabilitation programs on medication adherence in patients with cardiovascular disease: A systematic review and meta-analysis.

Background: Education to improve medication adherence is one of the core components of cardiac rehabilitation (CR) programs. However, the evidence on the effectiveness of CR programs on medication adherence is conflicting. Therefore, we aimed to summarize the effectiveness of CR programs versus standard care on medication adherence in patients with cardiovascular disease. Methods: A systematic review and meta-analysis was conducted. Seven databases and clinical trial registries were searched for published and unpublished articles from database inception to 09 Feb 2022. Only randomised controlled trials and quasi-experimental studies were included. Two independent reviewers conducted the screening, extraction, and appraisal. The JBI methodology for effectiveness reviews and PRISMA 2020 guidelines were followed. A statistical meta-analysis of included studies was pooled using RevMan version 5.4.1. Results: In total 33 studies were included with 16,677 participants. CR programs increased medication adherence by 14 % (RR = 1.14; 95 % CI: 1.07 to 1.22; p = 0.0002) with low degree of evidence certainty. CR also lowered the risk of dying by 17 % (RR = 0.83; 95 % CI: 0.69 to 1.00; p = 0.05); primary care and emergency department visit by mean difference of 0.19 (SMD = -0.19; 95 % CI: -0.30 to -0.08; p = 0.0008); and improved quality of life by 0.93 (SMD = 0.93; 95 % CI: 0.38 to 1.49; p = 0.0010). But no significant difference was observed in lipid profiles, except with total cholesterol (SMD = -0.26; 95 % CI: -0.44 to -0.07; p = 0.006) and blood pressure levels. Conclusions: CR improves medication adherence with a low degree of evidence certainty and non-significant changes in lipid and blood pressure levels. This result requires further investigation.

Effectiveness of alternative vs traditional exercises on cardiac rehabilitation program utilization in women with or at high risk of cardiovascular disease: a systematic review protocol.

OBJECTIVE: This review will evaluate the effectiveness of alternative vs traditional forms of exercise on cardiac rehabilitation program utilization and other outcomes in women with or at high risk of cardiovascular disease. INTRODUCTION: Exercise-based cardiac rehabilitation programs improve health outcomes in women with or at high risk of cardiovascular disease. However, such programs are underutilized worldwide, particularly among women. Some women perceive traditional gym-based exercise in cardiac rehabilitation programs (eg, typically treadmills, cycle ergometers, traditional resistance training) to be excessively rigorous and unpleasant, resulting in diminished participation and completion. Alternative forms of exercise such as yoga, tai chi, qi gong, or Pilates may be more enjoyable and motivating exercise options for women, enhancing engagement in rehabilitation programs. However, the effectiveness of these alternative exercises in improving program utilization is still inconsistent and needs to be systematically evaluated and synthesized. INCLUSION CRITERIA: This review will focus on randomized controlled trials of studies measuring the effectiveness of alternative vs traditional forms of exercise on cardiac rehabilitation program utilization as well as clinical, physiological, or patient-reported outcomes in women with or at high risk of cardiovascular disease. METHODS: The review will follow the JBI methodology for systematic reviews of effectiveness. Databases including MEDLINE (Ovid), CINAHL (EBSCOhost), Cochrane CENTRAL, Embase (Ovid), Emcare (Ovid), Scopus, Web of Science, LILACS, and PsycINFO (Ovid) will be searched. Two independent reviewers will screen articles and then extract and synthesize data. Methodological quality will be assessed using JBI's standardized instruments. GRADE will be used to determine the certainty of evidence. REVIEW REGISTRATION: PROSPERO CRD42022354996.

The effectiveness of interactive cardiac rehabilitation web applications versus usual care on programme completion in patients with cardiovascular disease: A systematic review and meta-analysis of randomised controlled trials.

INTRODUCTION: Although available evidence demonstrates positive clinical outcomes for patients attending and completing cardiac rehabilitation, the effectiveness of interactive cardiac rehabilitation web applications on programme completion has not been systematically examined. METHODS: This JBI systematic review of effects included studies measuring effectiveness of interactive cardiac rehabilitation web applications compared to telephone, and centre-based programmes. Outcome data were pooled under programme completion and clinical outcomes (body mass index, low-density lipoproteins, and blood pressure). Databases including MEDLINE (via Ovid), Cochrane Library, Scopus (via Elsevier) and CINAHL (via EBSCO) published in English were searched. Articles were screened and reviewed by two independent reviewers for inclusion, and the JBI critical appraisal tool and Grading of Recommendations Assessment, Development and Evaluation tool were applied to appraise and assess the certainty of the findings of the included studies. A meta-analysis of the primary and secondary outcomes used random effects models. RESULTS: In total, nine studies involving 1175 participants who participated in web-based cardiac rehabilitation to usual care were identified. The mean critical appraisal tool score was 76 (standard deviation: 9.7) with all (100%) studies scoring >69%, and the certainty of evidence low. Web-based programmes were 43% more likely to be completed than usual care (risk ratio: 1.43; 95% confidence interval: 0.96, 2.13) There was no difference between groups for clinical outcomes. DISCUSSION: Despite the relatively small number of studies, high heterogeneity and the limited outcome measures, the results appeared to favour web-based cardiac rehabilitation with regard to programme completion.

Efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus: A randomized SHAM-controlled trial.

AIMS: To determine the efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus (T2D), and any persistent benefits 7 weeks following treatment. METHODS: 50 participants with T2D were randomly assigned to either 1) 20x45-minute ECP sessions over 7 weeks (ECP45), 2) 20x30-minute ECP sessions over 7 weeks (ECP30) or 3) SHAM control. Outcomes were assessed at baseline, after 7 weeks of the intervention and 7 weeks after the interventions finished. Efficacy was determined from changes in HbA1c. RESULTS: After 7 weeks, there were significant between-group differences, with ECP45 lowering HbA1c compared to SHAM (mean [95% CI] -0.7 [-0.1 to -1.3] %; -7 [-1 to -15] mmol/mol). Within group changes were; ECP45 (mean ± SD -0.8 ± 0.8%; -8 ± 8 mmol/mol), ECP30 (-0.2 ± 0.5%; -2 ± 6 mmol/mol) and SHAM (-0.1 ± 0.9%; -1 ± 10 mmol/mol). HbA1c in the ECP45 group remained lower 7 weeks after completing the intervention; ECP45 (7.0 ± 1.1%; 53 ± 26 mmol/mol), ECP30 (7.7 ± 1.4%; 60 ± 16 mmol/mol) and SHAM (7.7 ± 1.0%; 60 ± 10 mmol/mol). CONCLUSIONS: In people with T2D, ECP45 for 7 weeks improved glycemic control when compared to ECP30 and a SHAM control group.

A Single Session of a Digital Health Tool-Delivered Exercise Intervention May Provide Immediate Relief from Pelvic Pain in Women with Endometriosis: A Pilot Randomized Controlled Study.

BACKGROUND: Endometriosis is a debilitating chronic condition that is commonly associated with chronic pelvic pain, affecting approximately 10% of women of reproductive age worldwide. The general principle of pain management in this population involves both pharmacological and surgical interventions. There is also increasing interest in the use of exercise as an alternative non-pharmacological analgesic, but adherence and accessibility to face-to-face exercise-delivery modalities are poor. This study aims to determine the immediate impact of a single session of 'supervised' telehealth-delivered exercise compared to 'self-managed' virtual reality (VR)-delivered exercise on pelvic pain associated with endometriosis. METHODS: Twenty-two women experiencing pelvic pain due to endometriosis were included and randomized into three groups: (i) VR-delivered exercise group (n = 8); (ii) telehealth-delivered exercise group (n = 8); and (iii) control group (n = 6). The visual analogue scale (VAS) was used to assess the severity of pelvic pain. RESULTS: There was no statistically significant between-group difference (p = 0.45) in the participants' pain score following a single session of the study interventions (VR or telehealth) or the control. However, a 'medium-to-large' group x time interaction effect (η2 = 0.10) was detected, indicating a more favorable pain score change following a single session of telehealth- (pre-post ∆: +10 ± 12 mm) and VR-delivered exercise (pre-post ∆: +9 ± 24 mm) compared to the control group (pre-post ∆: +16 ± 12 mm). CONCLUSIONS: Our study suggests that a single bout of a 'self-managed' VR-delivered exercise may be as efficacious as a single session of 'supervised' telehealth-delivered exercise in providing immediate relief from pelvic pain associated with endometriosis.

The Effects of Standardised versus Individualised Aerobic Exercise Prescription on Fitness-Fatness Index in Sedentary Adults: A Randomised Controlled Trial.

A poor Fitness Fatness Index (FFI) is associated with type 2 diabetes incidence, other chronic conditions (Alzheimer's, cancer, and cardiovascular disease) and all-cause mortality. Recent investigations have proposed that an individualised exercise prescription based on ventilatory thresholds is more effective than a standardised prescription in improving cardiorespiratory fitness (CRF), a key mediator of FFI. Thus, the aim of the current study was to determine the effectiveness of individualised versus standardised exercise prescription on FFI in sedentary adults. Thirty-eight sedentary individuals were randomised to 12-weeks of: (1) individualised exercise training using ventilatory thresholds (n = 19) or (2) standardised exercise training using a percentage of heart rate reserve (n = 19). A convenience sample was also recruited as a control group (n=8). Participants completed CRF exercise training three days per week, for 12-weeks on a motorised treadmill. FFI was calculated as CRF in metabolic equivalents (METs), divided by fatness determined by waist to height ratio (WtHR). A graded exercise test was used to measure CRF, and anthropometric measures (height and waist circumference) were assessed to ascertain WtHR. There was a difference in FFI change between study groups, whilst controlling for baseline FFI, F (2, 42) = 19.382 p < .001, partial η2 = 0.480. The magnitude of FFI increase from baseline was significantly higher in the individualised (+15%) compared to the standardised (+10%) (p = 0.028) and control group (+4%) (p = <.001). The main finding of the present study is that individualised exercise prescription had the greatest effect on improving FFI in sedentary adults compared to a standardised prescription. Therefore, an individualised based exercise prescription should be considered a viable and practical method of improving FFI in sedentary adults.

Changes in the Fitness Fatness Index following reduced exertion high-intensity interval training versus moderate-intensity continuous training in physically inactive adults.

Background: Many adults do not reach the recommended exercise participation guidelines, often citing lack of time as a barrier. Reduced exertion high-intensity training (REHIT) is a mode of exercise that takes as few as 10 min and has been shown to be as effective as other modalities. The Fitness Fatness Index (FFI) is a recently developed index that is used to predict cardiovascular disease (CVD) risk. The aim of this study was to determine the efficacy of a REHIT vs. a traditional moderate-intensity continuous training (MICT) on FFI in physically inactive adults. Methods: Thirty-two participants were randomized into one of two 8-week exercise intervention groups: (i) REHIT (n = 16); (ii) MICT (n = 16). The REHIT group performed 10 min of individualized cycling intervals on 2-4 days of the week. The MICT group were prescribed aerobic exercise at 50-65% of their heart rate reserve (HRR) on 3-5 days of the week. FFI was recorded at baseline and post 8-weeks, with FFI being calculated as cardiorespiratory fitness (CRF) (expressed as metabolic equivalents) divided by waist to height ratio (WtHR). A 1-unit increase in FFI was recognized as a clinically significant change in FFI. Results: The REHIT group showed significantly greater (+1.95, ±0.63) improvements in FFI compared to those in the MICT (+0.99, ±0.47) group (between group difference, p < 0.001). Furthermore, there was a greater proportion of participants who achieved a clinically significant change in FFI in the REHIT group (12/12, 100%) than in the MICT group (8/15, 53%) (between group difference, p = 0.01). Conclusion: This study suggests that REHIT may be a more efficacious exercise modality to increase FFI than MICT. This outcome is beneficial as the clinician can prescribe REHIT to physically inactive adults who cite lack of time as a barrier to physical activity participation and achieve significant reductions in CVD risk.

Changes in the Second Ventilatory Threshold Following Individualised versus Standardised Exercise Prescription among Physically Inactive Adults: A Randomised Trial.

The second ventilatory threshold (VT2) is established as an important indicator of exercise intensity tolerance. A higher VT2 allows for greater duration of higher intensity exercise participation and subsequently greater reductions in cardiovascular disease (CVD) risk. This study aimed to compare the efficacy of standardised and individualised exercise prescription on VT2 among physically inactive adults. Forty-nine physically inactive male and female participants (48.6 ± 11.5 years) were recruited and randomised into a 12-week standardised (n = 25) or individualised (n = 24) exercise prescription intervention. The exercise intensity for the standardised and individualised groups was prescribed as a percentage of heart rate reserve (HRR) or relative to the first ventilatory threshold (VT1) and VT2, respectively. Participants were required to complete a maximal graded exercise test at pre-and post-intervention to determine VT1 and VT2. Participants were categorised as responders to the intervention if an absolute VT2 change of at least 1.9% was attained. Thirty-eight participants were included in the analysis. A significant difference in VT2 change was found between individualised (pre vs. post: 70.6% vs. 78.7% maximum oxygen uptake (VO2max)) and standardised (pre vs. post: 72.5% vs. 72.3% VO2max) exercise groups. Individualised exercise prescription was significantly more efficacious (p = 0.04) in eliciting a positive response in VT2 (15/19, 79%) when compared to the standardised exercise group (9/19, 47%). Individualised exercise prescription appears to be more efficacious than standardised exercise prescription in eliciting a positive VT2 change among physically inactive adults. Increasing VT2 allows for greater tolerance to higher exercise intensities and therefore greater cardiovascular health outcomes.

Changes in Fitness-Fatness Index following a Personalized, Community-Based Exercise Program in Physically Inactive Adults: A Randomised Controlled Trial.

Fitness-fatness index (FFI) is used to identify those at high risk of developing type 2 diabetes and cardiovascular events. It is measured as the ratio between an individual's cardiorespiratory fitness (CRF) and waist-to-height ratio. Studies suggest that CRF and waist-to-height ratio are modifiable and can be improved by exercise. However, there is limited evidence surrounding a personalized approach to exercise prescription. This study investigated the impact of a 12-week personalized exercise program on FFI among sedentary individuals. It was hypothesized that the intervention would be effective in improving FFI in this cohort. One hundred and forty-two participants were randomized into two groups: i) personalised community-based intervention (n = 70); or ii) control (n = 72). Both groups underwent baseline anthropometric testing and a submaximal 'talk-test' to determine individual exercise intensities and baseline FFI. During the intervention, the control group underwent normal activities, whilst the treatment group received a 12-week personalised exercise program based on the American Council on Exercise (ACE) Integrated Fitness Training (IFT) guidelines. After 12-weeks, the treatment group demonstrated a significant increase in FFI (+13%), whilst the control group (-2%) showed a slight decrease (between-group difference, p = < 0.001). Both CRF (+12%) and waist-to-height (-2%) also showed significant favourable changes in the treatment group, with no change in the control group (between group difference, p = 0.01). These findings indicate that a personalised approach to exercise prescription using the ACE IFT guidelines are beneficial in reducing FFI. Consequently, FFI could be implemented within standardized approaches to exercise to help reduce the risk of developing chronic conditions.

A retrospective evaluation of the Brain and Body Fitness Studio service on functional capacity and quality of life in people with neurological disorders.

Background: People with neurological disorders (ND) are less physically active than the general population due to physical, sensory, and/or cognitive impairments. These individuals often feel intimidated to join mainstream health and wellness centers due to lack of specialized support for people with ND. The Brain and Body Fitness Studio (BBFS) is one of the first Accredited Exercise Physiologist-led interprofessional services in Adelaide South Australia to provide individualized evidence-based multimodal exercise prescription and social support for this population. This comprehensive retrospective study evaluated the impact of BBFS on functional capacity (FC) determined as the 6-min walk distance (6 MWD) achieved during a 6-min walk test (6 MWT), of its members with ND. Methods: Sixty-two BBFS members (age, 66 ± 10 years; 60% male) with ND (85% Parkinson's Disease; average time since diagnosis, 4 years [IQR, 2 to 12 years]) and complete pre- and post-6-month clinical assessment of the primary outcome of the study, the 6 MWD, were included in this retrospective analysis. A series of sub-analyses were also performed to investigate the effects of adherence to the recommended prescription of at least twice a week in the program (≥80 vs. < 80% adherence), and disease stage (time since diagnosis; ≥6 vs. < 6 years) on FC. Results: Although there was no statistically significant change in 6 MWD from pre- to post-6-month BBFS program (+15 ± 90 m, p = 0.19), a clinically meaningful improvement of >14 m was evident. Improvement in 6 MWD was significantly greater in members who attended at least 80% of the recommended visits (≥80% visits, +37 ± 58 m; ≤ 80% visits,-1 ± 105 m, p = 0.046). We also found a 6 MWD improvement from pre- to post-6 months in those in the early years of their ND (< 6 years since diagnosis, +39 ± 76 m), but not in those in the later years of their ND (≥6 years since diagnosis, -36 ± 123 m, between group difference, p = 0.029). Conclusion: A clinically meaningful 6 MWD improvement may be elicited by services provided by BBFS in people with ND. Overall, the benefits appear to be more evident in members who attended the BBFS for at least 80% of the recommended visits and those who were in the early stage of their ND diagnosis.

Exercise Training Intensity and the Fitness-Fatness Index in Adults with Metabolic Syndrome: A Randomized Trial.

BACKGROUND: Cardiorespiratory fitness and fatness (notably central obesity) are mediating factors of the metabolic syndrome (MetS) and consequent cardiovascular disease (CVD)/mortality risk. The fitness-fatness index (FFI) combines these factors and has been reported to be a better indicator of CVD and all-cause mortality risk, beyond the capacity of either fitness or fatness alone. OBJECTIVE: This study sought to investigate the effects of different exercise intensities on FFI in adults with MetS. METHODS: This was a sub-study of the 'Exercise in the prevention of Metabolic Syndrome' (EX-MET) multicentre trial. Ninety-nine adults diagnosed with MetS according to the International Diabetes Federation criteria were randomized to one of the following 16-week exercise interventions: i) moderate-intensity continuous training (MICT) at 60-70% HRpeak for 30 min/session (n = 34, 150 min/week); ii) 4 × 4 min bouts of high-intensity interval training at 85-95% HRpeak, interspersed with 3-min active recovery at 50-70% HRpeak (n = 34, 38 min/session, 114 min/week); and iii) 1 × 4 min bout of HIIT at 85-95% HRpeak (n = 31, 17 min/session, 51 min/week). Cardiorespiratory fitness (peak oxygen uptake, V̇O2peak) was determined via indirect calorimetry during maximal exercise testing and fatness was the ratio of waist circumference-to-height (WtHR). FFI was calculated as V̇O2peak in metabolic equivalents (METs) divided by WtHR. A clinically meaningful response to the exercise intervention was taken as a 1 FFI unit increase. RESULTS: Seventy-seven participants completed pre and post testing to determine FFI. While there was no significant between group difference (p = 0.30), there was a small group x time interaction effect on FFI [F(2, 73) = 1.226; η2 = 0.01], with numerically greater improvements following HIIT (4HIIT, + 16%; 1HIIT, + 11%) relative to MICT (+ 7%). There was a greater proportion of participants who had a clinically meaningful change in FFI following high-volume HIIT (60%, 15/25) and low-volume HIIT (65%, 17/26) compared to MICT (38%, 10/26), but with no significant between-group difference (p = 0.12). A similar trend was found when a sub-analysis comparing the FFI between those with type 2 diabetes (MICT, 33%, 3/9; high-volume HIIT, 64%, 7/11; and low-volume HIIT, 58%, 7/12) and without type 2 diabetes (MICT, 41%, 7/17; high-volume HIIT, 57%, 8/14; low-volume HIIT, 71%, 10/14). CONCLUSION: Although there were no statistically significant differences detected between groups, this study suggests that the response to changes in FFI in adults with MetS may be affected by exercise intensity, when numerical differences between exercise groups are considered. Further research is warranted. Trial registration number and date of registration: ClinicalTrials.gov NCT01676870; 31/08/2012.

Genome wide association study of response to interval and continuous exercise training: the Predict-HIIT study.

BACKGROUND: Low cardiorespiratory fitness (V̇O2peak) is highly associated with chronic disease and mortality from all causes. Whilst exercise training is recommended in health guidelines to improve V̇O2peak, there is considerable inter-individual variability in the V̇O2peak response to the same dose of exercise. Understanding how genetic factors contribute to V̇O2peak training response may improve personalisation of exercise programs. The aim of this study was to identify genetic variants that are associated with the magnitude of V̇O2peak response following exercise training. METHODS: Participant change in objectively measured V̇O2peak from 18 different interventions was obtained from a multi-centre study (Predict-HIIT). A genome-wide association study was completed (n = 507), and a polygenic predictor score (PPS) was developed using alleles from single nucleotide polymorphisms (SNPs) significantly associated (P < 1 × 10-5) with the magnitude of V̇O2peak response. Findings were tested in an independent validation study (n = 39) and compared to previous research. RESULTS: No variants at the genome-wide significance level were found after adjusting for key covariates (baseline V̇O2peak, individual study, principal components which were significantly associated with the trait). A Quantile-Quantile plot indicates there was minor inflation in the study. Twelve novel loci showed a trend of association with V̇O2peak response that reached suggestive significance (P < 1 × 10-5). The strongest association was found near the membrane associated guanylate kinase, WW and PDZ domain containing 2 (MAGI2) gene (rs6959961, P = 2.61 × 10-7). A PPS created from the 12 lead SNPs was unable to predict V̇O2peak response in a tenfold cross validation, or in an independent (n = 39) validation study (P > 0.1). Significant correlations were found for beta coefficients of variants in the Predict-HIIT (P < 1 × 10-4) and the validation study (P < × 10-6), indicating that general effects of the loci exist, and that with a higher statistical power, more significant genetic associations may become apparent. CONCLUSIONS: Ongoing research and validation of current and previous findings is needed to determine if genetics does play a large role in V̇O2peak response variance, and whether genomic predictors for V̇O2peak response trainability can inform evidence-based clinical practice. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR), Trial Id: ACTRN12618000501246, Date Registered: 06/04/2018, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374601&isReview=true .

Effect of Different Volumes of Interval Training and Continuous Exercise on Interleukin-22 in Adults with Metabolic Syndrome: A Randomized Trial.

INTRODUCTION: IL-22 may have a role in the alleviation of the metabolic syndrome (MetS) via protection of pancreatic beta and endothelial cells from oxidative and lipid-induced damage. We aimed to investigate the effects of moderate-intensity continuous training (MICT) and different volumes of high-intensity interval training (HIIT) on changes in circulating IL-22. METHODS: This was a sub-study of the "Exercise in the prevention of Metabolic Syndrome" (EX-MET) a multi-center, randomized trial. This study used data collected at the Brisbane site. Thirty-nine individuals with MetS were randomized to one of three 16-wk interventions: 1) MICT (n=10, 30min at 60-70% HR peak, 5x/wk); 2) 4HIIT (n=13, 4x4min at 85-95% HR peak, interspersed with 3min of active recovery at 50-70% HR peak, 3x/wk); or 3) 1HIIT (n=16, 1x4min at 85-95% HR peak, 3x/wk). Serum IL-22 concentration was measured following a 12-hr fast via an enzyme linked immunosorbent assay, before and after the intervention. MetS severity, insulin resistance (IR), visceral adipose tissue (VAT), and cardiorespiratory fitness (CRF) were also measured via MetS z-score, HOMA-IR, dual-energy X-ray absorptiometry, and indirect calorimetry (maximal exercise test), respectively. RESULTS: The median (IQR) IL-22% changes from pre- to post-intervention in the MICT, 4HIIT, and 1HIIT groups were -17% (-43.0% to 31.3%), +16.5% (-18.9% to 154.9%), and +15.9% (-28.7% to 46.1%), respectively. Although there were no significant between-group differences in IL-22 concentration change, there was a medium-to-large group × time interaction effect [F(2,35)=2.08, p=0.14, η2=0.14]. CONCLUSION: Although there was no statistically significant between-group difference in IL-22 change, the study suggests that different exercise intensities may have opposing effects on IL-22 concentration in individuals with MetS.

Alterations to neuromuscular properties of skeletal muscle are temporally dissociated from the oxygen uptake slow component.

To assess if the alteration of neuromuscular properties of knee extensors muscles during heavy exercise co-vary with the SCV ([Formula: see text] slow component), eleven healthy male participants completed an incremental ramp test to exhaustion and five constant heavy intensity cycling bouts of 2, 6, 10, 20 and 30 minutes. Neuromuscular testing of the knee extensor muscles were completed before and after exercise. Results showed a significant decline in maximal voluntary contraction (MVC) torque only after 30 minutes of exercise (-17.01% ± 13.09%; p < 0.05) while single twitch (PT), 10 Hz (P10), and 100 Hz (P100) doublet peak torque amplitudes were reduced after 20 and 30 minutes (p < 0.05). Voluntary activation (VA) and M-wave were not affected by exercise, but significant correlation was found between the SCV and PT, MVC, VA, P10, P100, and P10/P100 ratio, respectively (p < 0.015). Therefore, because the development of the SCV occurred mainly between 2-10 minutes, during which neuromuscular properties were relatively stable, and because PT, P10 and P100 were significantly reduced only after 20-30 minutes of exercise while SCV is stable, a temporal relationship between them does not appear to exist. These results suggest that the development of fatigue due to alterations of neuromuscular properties is not an essential requirement to elicit the SCV.

Optimizing the Interaction of Exercise Volume and Metformin to Induce a Clinically Significant Reduction in Metabolic Syndrome Severity: A Randomised Trial.

Insulin resistance is a central mediating factor of the metabolic syndrome (MetS), with exercise training and metformin proven antidotes to insulin resistance. However, when the two therapies are combined there is conflicting data regarding whether metformin blunts or improves exercise training-induced adaptations. The volume of exercise (duration, intensity, and frequency) on the interaction of exercise training and metformin has yet to be investigated. The aim of this study is therefore to explore the impact of a combination of different exercise volumes and metformin on MetS severity. This is a secondary analysis of data from one of the sites of the 'Exercise in Prevention of Metabolic Syndrome' (EX-MET) study. Ninety-nine adults with MetS were randomized into a 16-week exercise program completing either: (i) moderate-intensity continuous training (MICT) at 60-70% of peak heart rate (HRpeak) for 30 min/session (n = 34, 150 min/week); (ii) high-volume high-intensity interval training (HIIT) consisting of 4 × 4 min bouts at 85-95% HRpeak, interspersed with 3 min of active recovery at 50-70% HRpeak (n = 34, 38 min/session, 114 min/week); or (iii) low volume HIIT, 1 × 4 min bout of HIIT at 85-95% HRpeak (n = 31, 17 min/session, 51 min/week). Metformin intake was monitored and recorded throughout the trial. MetS severity was calculated as z-scores derived from MetS risk factors assessed at pre- and post-intervention. Sixty-five participants had complete pre- and post-intervention data for MetS z-score, of which 18 participants (28%) were taking metformin. Over the 16-week intervention, a similar proportion of participants clinically improved MetS severity (Δ ≥ -0.87) with metformin (8/18, 44%) or without metformin (23/47, 49%) (p = 0.75). While there were no between-group differences (p = 0.24), in those who did not take metformin low-volume HIIT had more likely responders (10/15, 67%) compared to MICT (6/16, 38%) and high-volume HIIT (7/16, 44%). In those taking metformin, there was a lower proportion of participants who clinically improved MetS severity following high-volume HIIT (1/6, 17%) compared to MICT (2/4, 50%) and low-volume HIIT (5/8, 63%), but with no between-group difference (p = 0.23). Moreover, in those who performed high-volume HIIT, there was a statistically significantly higher proportion (p = 0.03) of likely non-responders with improved MetS severity in participants taking metformin (4/6, 67%) compared to those not taking metformin (3/16, 19%). In individuals with MetS, the effect of high volume HIIT on MetS severity may be blunted in those taking metformin. These findings need to be confirmed in a larger study.

The metabolic profiles of different fiber type populations under the emergence of the slow component of oxygen uptake.

To investigate the influence of different metabolic muscle fiber profiles on the emergence of the slow component of oxygen uptake ([Formula: see text]SC), 12 habitually active males completed four sessions of different combinations of work-to-work transition exercises up to severe intensity. Each transition was modeled to analyze the different kinetic parameters. Using a new approach, combining Henneman's principle and superposition principle, a reconstructed kinetics was built by temporally aligning the start of each new transition and summing them. The primary phase time constant significantly slowed and the gain at the end (GainEnd) significantly increased when transitions started from a higher intensity (p < 0.001). Kinetic parameters from the reconstructed curve ([Formula: see text], time delay of primary phase, [Formula: see text]End and GainEnd) were not significantly different from one transition to severe exercise. These results suggest that the appearance of the [Formula: see text]SC is at least related to, if not the result of, the different metabolic properties of muscle fibers.