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Objectives: Greater arterial stiffness and poor 24h blood pressure (BP) are recognized as indicators of poor cardiovascular health. Evidence has shown that high intensity interval training (HIIT) may be a superior alternative to moderate intensity continuous training (MICT) for improving cardiovascular disease risk factors such as cardiorespiratory fitness and vascular function. However, there are limited data comparing the effect of HIIT to MICT on central arterial stiffness and/or 24h BP response. The purpose of this study was to compare HIIT versus MICT on central arterial stiffness and 24h BP outcomes by systematic review and meta-analysis., Design: A systematic review and meta-analysis was conducted., Methods: Eligible studies were exercise training interventions (≥4weeks) that included both HIIT and MICT and reported central arterial stiffness, as measured by pulse wave velocity and augmentation index and/or 24h BP outcome measures., Results: HIIT was found to be superior to MICT for reducing night-time diastolic BP (ES: -0.456, 95% CI: -0.826 to -0.086mmHg; P=0.016). A near-significant greater reduction in daytime systolic (ES: -0.349, 95% CI: -0.740 to 0.041mmHg; p=0.079) and diastolic BP was observed with HIIT compared to MICT (ES: -0.349, 95% CI: -0.717 to 0.020mmHg; p=0.063). No significant difference was found for other BP responses or arterial stiffness outcomes., Conclusions: HIIT leads to a superior reduction in night-time diastolic BP compared to MICT. Furthermore, a near-significant greater reduction in daytime BP was found with HIIT compared to MICT. No significant difference was observed for changes to central arterial stiffness between HIIT and MICT., (Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Objectives: Engagement in high volumes of physical activity coupled with energy restriction during periods of musculoskeletal development may compromise bone health. Jockeys limit caloric intakes on a weekly basis often from their mid-to-late teens. The aim of this study was to establish whether calcium and vitamin D supplementation would improve bone turnover markers (BTM) and non-weight bearing bone properties of young male jockeys., Design: A six-month randomised, double-blinded, placebo-controlled trial with two groups of apprentice male jockeys was conducted., Methods: Participants (age 20.18±3.23years) were supplemented with 800mg of calcium and 400IU of vitamin D (n=8) or a placebo (n=9) daily. Bone properties were assessed at the ultra-distal (4%) and proximal (66%) radius using pQCT at baseline and six months. Vitamin D, P1NP and CTX were assessed., Results: ANCOVA results for blood-borne markers indicated higher vitamin D levels (18.1%, p=0.014, partial η 2 =0.38) and lower CTX (ng·L -1 ) (-24.8%, p=0.011, partial η 2 =0.40) in the supplemented group with no differences observed in P1NP. Analysis of bone variables indicated no between group differences in either trabecular or cortical bone properties at the 4% and 66% sites post-intervention., Conclusions: This trial is the first to examine the efficacy of calcium and vitamin D supplementation in improving non-weight bearing bone properties in a young male athletic population. Results indicate positive alterations to bone metabolism; however, longer duration or higher dosage appears to be required to detect changes in bone material properties at the radius. Further examination of such interventions in weight-restricted athletes is warranted., (Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Objectives: This study aimed to review the efficacy of exercise training for improving cutaneous microvascular reactivity in response to local stimulus in human adults., Design: Systematic review with meta-analysis., Methods: A systematic search of Medline, Cinahl, AMED, Web of Science, Scopus, and Embase was conducted up to June 2015. Included studies were controlled trials assessing the effect of an exercise training intervention on cutaneous microvascular reactivity as instigated by local stimulus such as local heating, iontophoresis and post-occlusive reactive hyperaemia. Studies where the control was only measured at baseline or which included participants with vasospastic disorders were excluded. Two authors independently reviewed and selected relevant controlled trials and extracted data. Quality was assessed using the Downs and Black checklist., Results: Seven trials were included, with six showing a benefit of exercise training but only two reaching statistical significance with effect size ranging from -0.14 to 1.03. The meta-analysis revealed that aerobic exercise had a moderate statistically significant effect on improving cutaneous microvascular reactivity (effect size (ES)=0.43, 95% CI: 0.08-0.78, p=0.015)., Conclusions: Individual studies employing an exercise training intervention have tended to have small sample sizes and hence lacked sufficient power to detect clinically meaningful benefits to cutaneous microvascular reactivity. Pooled analysis revealed a clear benefit of exercise training on improving cutaneous microvascular reactivity in older and previously inactive adult cohorts. Exercise training may provide a cost-effective option for improving cutaneous microvascular reactivity in adults and may be of benefit to those with cardiovascular disease and metabolic disorders such as diabetes., (Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Type 2 diabetes mellitus (T2DM) and pre-diabetic conditions such as impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) are rapidly increasing in prevalence. There is compelling evidence that T2DM is more likely to develop in individuals who are insufficiently active. Exercise training, often in combination with other lifestyle strategies, has beneficial effects on preventing the onset of T2DM and improving glycaemic control in those with pre-diabetes. In addition, exercise training improves cardiovascular risk profile, body composition and cardiorespiratory fitness, all strongly related to better health outcomes. Based on the evidence, it is recommended that patients with T2DM or pre-diabetes accumulate a minimum of 210 min per week of moderate-intensity exercise or 125 min per week of vigorous intensity exercise with no more than two consecutive days without training. Vigorous intensity exercise is more time efficient and may also result in greater benefits in appropriate individuals with consideration of complications and contraindications. It is further recommended that two or more resistance training sessions per week (2-4 sets of 8-10 repetitions) should be included in the total 210 or 125 min of moderate or vigorous exercise, respectively. It is also recommended that, due to the high prevalence and incidence of comorbid conditions in patients with T2DM, exercise training programs should be written and delivered by individuals with appropriate qualifications and experience to recognise and accommodate comorbidities and complications., (Copyright © 2011 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)