Menstrual cycle patterns and their relationship with measures of well-being and perceived performance metrics in competitive and recreational resistance-trained athletes.

BACKGROUND: There is mixed evidence on how the menstrual cycle (MC) affects sports performance, with many studies showing variations in performance during different phases of the MC, while other evidence shows that the MC's effects on performance may be trivial. Therefore, this exploratory longitudinal monitoring study was designed to investigate MC characteristics and symptoms in a resistance-trained (RT) population to look for associations between measures of well-being and perceived performance metrics across the MC. METHODS: RT females reported their workout habits, perceived performance metrics, and measures of well-being while tracking their MC with detailed methods via daily check-ins in an app. RESULTS: Most MC characteristics and symptoms in the present RT population aligned with previous research on the general population. However, the frequency of irregular cycles was higher than in previous research on the general population. The amount of individual variation and within-subject cycle-to-cycle variation in MC characteristics and MC symptoms was also high. All measures of well-being were significantly associated with specific days of the MC, demonstrating a change in well-being based on the timing of the MC. Several perceived performance metrics were significantly associated with changes across the MC, while others were not. CONCLUSIONS: Overall, with the current evidence as it stands, a highly individualized approach should be taken for any training or performance considerations surrounding the MC due to the high levels of individual variation.

A Preliminary Investigation into the Frequency Dose Effects of High-Intensity Functional Training on Cardiometabolic Health.

The objective of this study was to explore the effects of three weekly frequency doses of high-intensity functional training (HIFT) on an array of cardiometabolic markers in adults with metabolic syndrome (MetS). Twenty-one men and women, randomized into one (HIFT1), two (HIFT2), or three (HIFT3) days per week of HIFT, completed 3-weeks of familiarization plus a 12-week progressive training program. Pre- and post-intervention, several cardiometabolic, body composition, oxygen consumption, metabolic syndrome severity, and perceptions of fitness measurements were assessed. Additionally, an exercise enjoyment survey was administered post-intervention. A Cohen's d was used to demonstrate within-group change effect size. Although this study was not fully powered, a one-way and two-way ANOVA were used to compare the dose groups to provide provisional insights. No differences were found when frequency dose groups were compared. Many cardiometabolic, body composition, and fitness improvements were seen within each group, with clinically meaningful improvements in the metabolic syndrome severity score (MSSS) (HIFT1: -0.105, d = 0.28; HIFT2: -0.382, d = 1.20; HIFT3: -0.467, d = 1.07), waist circumference (HIFT1: -4.1cm, d = 3.33; HIFT2: -5.4cm, d = 0.89; HIFT3: -0.7cm, d = 0.20), and blood glucose (HIFT1: -9.5mg/dL, d = 0.98; HIFT2: -4.9mg/dL, d = 1.00; HIFT3: -1.7mg/dL, d = 0.23). All three groups similarly reported high exercise enjoyment and likeliness to continue after the intervention. In conclusion, HIFT performed once, twice, or thrice a week elicits improvements in MetS and is considered enjoyable. HIFT, even at a low weekly dose, therefore represents a potential strategy to reduce the global MetS burden.

The Effects of a Single Session of High Intensity Functional Training on Energy Expenditure, VO2, and Blood Lactate.

High intensity functional training (HIFT) provides a potential option to meet public exercise recommendations for both cardiorespiratory and strength outcomes in a time efficient manner. To better understand the potential for HIFT as an exercise approach, energy expenditure (EE) and relative intensity need quantifying. In thirteen sedentary men and women with metabolic syndrome (MetS), we used both indirect calorimetry and blood lactate levels to calculate EE of a single session of HIFT. The HIFT session included four, 6-minute sets of consecutive functional exercises. Examples of the exercises involved were squats, deadlifts, suspension rows, suspension chest press, and planks. Intensity is described relative to individual ventilatory thresholds. The total group EE was 270.3 ± 77.3 kcal with approximately 5% attributed anaerobic energy production. VO2 ranged between 88.8 ± 12.3% and 99 ± 12% of the second ventilatory threshold (VT2), indicating a vigorous effort. After each work interval, peak blood lactate ranged between 7.9 ± 1.9 and 9.3 ± 2.9 mmol, and rate of perceived exertion between 6.9 ± 1.0 and 8.7 ± 0.8 arbitrary units from 1-10. These were achieved in approximately 46 minutes of exercise per participant. In conclusion, HIFT elicits the energy expenditure and effort requisite to result in the adaptive responses to produce the known suite of benefits of exercise for individuals with MetS.

Impact of high-intensity interval training including Indigenous narratives on adolescents' mental health: a cluster-randomised controlled trial.

OBJECTIVES: We investigated the efficacy of teacher-delivered high-intensity interval training (HIIT) with Indigenous narrative options on the mental health of school students in low-mid socioeconomic areas, compared to standard curriculum physical education practice. METHODS: A cluster-randomised controlled trial was conducted in eight schools (N=368, age range 11-13 years) over 16 weeks. The primary outcome was the Strengths and Difficulties Questionnaire (SDQ) score. Generalised linear mixed models, controlling for the SDQ at baseline were applied, expressed as ß, 95% confidence intervals, standardised effect, and p-value. Focus groups elicited experiences with participating in and delivering the intervention. RESULTS: There were no clear effects for SDQ total score (ß -0.15, CI -0.98 - 0.67, SE 0.42, p=0.714). Teachers did not deliver the Indigenous narrative options consistently owing to the perceived preparation needed and lack of confidence. CONCLUSIONS: HIIT delivered in this manner had no effect on self-perceived psychological difficulty or mental wellbeing in a cohort of young adolescents. IMPLICATIONS FOR PUBLIC HEALTH: Future research should continue to explore opportunities to improve mental wellbeing via physical activity, but HIIT should not be implemented as a universal intervention for mental health gains alone. Teachers need more support to utilise Indigenous narratives as part of HIIT delivery.

Scaling-Up Adolescent High-Intensity Interval Training Programs for Population Health.

High-intensity interval training (HIIT) has become a polarizing form of exercise. In this article, we argue that adolescent HIIT programs can have population health impact if they are (i) integrated into existing opportunities, (ii) designed to develop physical literacy, (iii) delivered in an engaging manner, and (iv) guided and supported by an implementation framework that addresses relevant barriers and facilitators.

Feasibility and Provisional Efficacy of Embedding High-Intensity Interval Training Into Physical Education Lessons: A Pilot Cluster-Randomized Controlled Trial.

PURPOSE: The aim of this study was to determine the feasibility of generalist school teachers delivering curriculum connected high-intensity interval training in a school's physical education class time. METHOD: Two schools volunteered to participate. A total of 84 students (11.9 [0.5] y, M = 64 and F = 19) volunteered to participate. Four classes from 2 schools were randomized to either intervention (n = 53) or control (n = 31) for one school term (8 wk). Intervention class teachers participated in a 1-day workshop instructing them how to deliver twice weekly, high-intensity interval training sessions. The control classes continued with their usual physical education curriculum. Recruitment, intervention fidelity, and program satisfaction were assessed. Preliminary efficacy (primary outcome cardiorespiratory fitness) was quantified using generalized linear mixed models, expressed as effect size. A range of secondary outcomes was also assessed. RESULTS: The recruitment rate was 88%. About 84% of the sessions were delivered. The heart rate peak over all sessions was 89.6% (13%) of the predicted maximum. The intervention teachers reported high levels of satisfaction. Almost all student participants were positive about participating. No adverse events occurred. The adjusted between-group difference for cardiorespiratory fitness was trivial (effect size 0.02). CONCLUSIONS: This teacher-delivered high-intensity interval training program was feasible and acceptable to both teachers and student participants. It is therefore potentially scalable.

Tectonic and climatic drivers of Asian monsoon evolution.

Asian Monsoon rainfall supports the livelihood of billions of people, yet the relative importance of different drivers remains an issue of great debate. Here, we present 30 million-year model-based reconstructions of Indian summer monsoon and South East Asian monsoon rainfall at millennial resolution. We show that precession is the dominant direct driver of orbital variability, although variability on obliquity timescales is driven through the ice sheets. Orographic development dominated the evolution of the South East Asian monsoon, but Indian summer monsoon evolution involved a complex mix of contributions from orography (39%), precession (25%), atmospheric CO2 (21%), ice-sheet state (5%) and ocean gateways (5%). Prior to 15 Ma, the Indian summer monsoon was broadly stable, albeit with substantial orbital variability. From 15 Ma to 5 Ma, strengthening was driven by a combination of orography and glaciation, while closure of the Panama gateway provided the prerequisite for the modern Indian summer monsoon state through a strengthened Atlantic meridional overturning circulation.

A preliminary evaluation of a client-centred prompting tool for supporting everyday activities in individuals with mild to moderate levels of cognitive impairment due to dementia.

OBJECTIVES: Technology-based prompting has the potential to support people with dementia to complete multistep tasks in the home. However, these devices can be complex to use. This paper reports a feasibility trial of a personalised touchscreen digital prompter designed for home use.Methodology: A tablet-based prompter suitable for people living with dementia was developed, along with a detailed guidance manual. Carers loaded instructions for completing the task onto the prompter, and the person with dementia then used the tablet independently to complete a task. Eleven couples used the prompter 'out-of-the-box' with no support other than a guidance manual. RESULTS: The majority of participants with dementia could follow the steps on the prompter, and carers were able to breakdown and load tasks onto the prompter. Eight couples used the prompter successfully to complete goals that they had identified in advance. These included preparing simple snacks and using a TV remote control. Successfully achieving goals was associated with more frequent use of the prompting screen on more days, but not higher levels of editing or previewing of tasks. CONCLUSION: The study provides the preliminary evidence that family caregivers can use a touchscreen tablet, software and manual package to identify specific tasks and break these down into steps and that people living with dementia can then follow the prompts to complete the tasks. This potentially represents an important advance in dementia care. Further testing is required to establish efficacy and to identify any factors that impact on outcomes.

Integrating high-intensity interval training into the workplace: The Work-HIIT pilot RCT.

The purpose of this study was to assess the feasibility and preliminary efficacy of a high-intensity interval training (HIIT) intervention integrated into the workplace on physical and mental health outcomes in a sample of adults. The Work-HIIT intervention was evaluated at the University of Newcastle (March-July 2019). University employees (18+ years) who self-identified as predominantly sedentary at work (n = 47, 43.0 ± 10.7 years; 41 female) were recruited, screened, and randomized after baseline assessments into Work-HIIT (n = 24) or wait-list control (n = 23) conditions. Participants were asked to attend 2-3 researcher-facilitated HIIT sessions/week (weeks 1-8). Sessions included a 2-minute gross-motor warm-up, followed by various combinations of aerobic and muscular fitness exercises lasting 8 minutes (using 30:30 second work: rest intervals). Program feasibility was assessed using measures of satisfaction, compliance, adherence, fidelity, and retention. Physiological and psychological outcomes were measured at baseline and 9 weeks. Feasibility data were investigated using descriptive statistics and efficacy outcomes determined using linear mixed models and Cohen's d effect sizes. Participant ratings showed high levels of satisfaction (4.6/5); 71% of participants attended ≥2 sessions/wk and averaged 85.9% HRmax across all sessions (including rest and work intervals). Small-to-medium positive effects resulted for cardiorespiratory fitness [+2.9 laps, 95% CI (-4.19-10.14); d = 0.34] and work productivity [+0.26, d = 0.47]. Large positive effects resulted for muscular fitness [push-ups +3.5, d = 0.95; standing jump +10.1 cm, d = 1.12]; HIIT self-efficacy [+16.53, d = 1.57]; sleep [weekday +0.76 hours, d = 1.05]; and autonomous motivation [+0.23, d = 0.76]. This study supports the feasibility and preliminary efficacy of facilitator-led Work-HIIT as a time-efficient, enjoyable, and convenient workplace exercise option for adults.

Development and Evaluation of the High-Intensity Interval Training Self-Efficacy Questionnaire.

This study involved the design and evaluation of the High-Intensity Interval Training Self-Efficacy Questionnaire (HIIT-SQ). Phase 1: Questionnaire items were developed. Phase 2: Australian adolescents (N = 389, 16.0 ± 0.4 years, 41.10% female) completed the HIIT-SQ, and factorial validity of the measurement model was explored. Phase 3: Adolescents (N = 100, age 12-14 years, 44% female) completed the HIIT-SQ twice (1 week apart) to evaluate test-retest reliability. Confirmatory factor analysis of the final six items (mean = 3.43-6.73, SD = 0.99-25.30) revealed adequate fit, χ2(21) = 21, p = .01, comparative fit index = .99, Tucker-Lewis index = .99, root mean square of approximation = .07, 90% confidence interval [.04, .11]. Factor loading estimates showed that all items were highly related to the factor (estimates range: 0.81-0.90). Intraclass coefficients and typical error values were .99 (95% confidence interval [.99, 1.00]) and .22, respectively. This study provides preliminary evidence for the validity and reliability of scores derived from the HIIT-SQ in adolescents.

Time Course Changes in Confirmed 'True' VO 2 max After Individualized and Standardized Training.

This study sought to examine time course changes in maximal oxygen consumption (VO 2 max) confirmed with verification testing following 12 weeks of standardized vs. individualized exercise training. Participants (N=39) were randomly allocated to differing exercise intensity prescription groups: ventilatory threshold (individualized) or % heart rate reserve (standardized). At baseline, 4, 8, and 12 weeks, participants completed maximal exercise testing with a verification protocol to confirm 'true VO 2 max.' VO 2 max in the standardized group changed from 24.3±4.6 ml·kg -1 ·min -1 at baseline to 24.7±4.6, 25.9±4.7, and 26.0±4.2 ml·kg -1 ·min -1 at week 4, 8, and 12, respectively, with a significant difference (p<0.05) in VO 2 max at week 8 and 12 compared to baseline. The individualized group had increases in VO 2 max from online 2 9.5±7.5 ml·kg -1 ·min -1 at baseline to 30.6±8.4, 31.4±8.4, and 32.8±8.6 ml·kg -1 ·min -1 at week 4, 8, and 12, respectively. In the individualized group, there were significant differences (p<0.05) in VO 2 max from baseline to week 8 and 12 and a significant increase in VO 2 max from week 8 to 1 online 2 . Although not statistically significant, our preliminary data demonstrates a more rapid and potent improvement in VO 2 max when exercise intensity is individualized. This is the first investigation to employ use of the verification procedure to confirm 'true VO 2 max' changes following exercise training using ventilatory thresholds.

School-based physical activity intervention for older adolescents: rationale and study protocol for the Burn 2 Learn cluster randomised controlled trial.

INTRODUCTION: This trial aims to investigate the impact of a school-based physical activity programme, involving high-intensity interval training (HIIT), on the physical, mental and cognitive health of senior school students. METHODS AND ANALYSIS: The Burn 2 Learn (B2L) intervention will be evaluated using a two-arm parallel group cluster randomised controlled trial with allocation occurring at the school level (to treatment or wait-list control). Schools will be recruited in two cohorts from New South Wales, Australia. The trial will aim to recruit ~720 senior school students (aged 16-18 years) from 20 secondary schools (ie, 10 schools per cohort). A range of implementation strategies will be provided to teachers (eg, training, equipment and support) to facilitate the delivery of HIIT sessions during scheduled classes. In phase I and II (3 months each), teachers will facilitate the delivery of at least two HIIT sessions/week during lesson-time. In phase III (6 months), students will be encouraged to complete sessions outside of lesson-time (teachers may continue to facilitate the delivery of B2L sessions during lesson-time). Study outcomes will be assessed at baseline, 6 months (primary end point) and 12 months. Cardiorespiratory fitness (shuttle run test) is the primary outcome. Secondary outcomes include: vigorous physical activity, muscular fitness, cognition and mental health. A subsample of students will (i) provide hair samples to determine their accumulated exposure to stressful events and (ii) undergo multimodal MRI to examine brain structure and function. A process evaluation will be conducted (ie, recruitment, retention, attendance and programme satisfaction). ETHICS AND DISSEMINATION: This study has received approval from the University of Newcastle (H-2016-0424) and the NSW Department of Education (SERAP: 2017116) human research ethics committees. TRIAL REGISTRATION NUMBER: ACTRN12618000293268; Pre-results.

Incidence of V˙O2max Responders to Personalized versus Standardized Exercise Prescription.

INTRODUCTION: Despite knowledge of cardiorespiratory fitness (CRF) training responders and nonresponders, it is not well understood how the exercise intensity prescription affects the incidence of response. The purpose of this study was to determine CRF training responsiveness based on cohort-specific technical error after 12 wk of standardized or individually prescribed exercise and the use of a verification protocol to confirm maximal oxygen uptake (V˙O2max). METHODS: Sedentary adult participants (9 men, 30 women; 48.2 ± 12.2 yr) completed exercise training on 3 d·wk for 12 wk, with exercise intensity prescribed based on standardized methods using heart rate reserve or an individualized approach using ventilatory thresholds. A verification protocol was used at baseline and 12 wk to confirm the identification of a true V˙O2max and subsequent relative percent changes to quantify CRF training responsiveness. A cohort-specific technical error (4.7%) was used as a threshold to identify incidence of response. RESULTS: Relative V˙O2max significantly increased (P < 0.05) from 24.3 ± 4.6 to 26.0 ± 4.2 and 29.2 ± 7.5 to 32.8 ± 8.6 mL·kg·min for the standardized and individualized groups, respectively. Absolute V˙O2max significantly increased (P < 0.05) from 2.0 ± 0.6 to 2.2 ± 0.6 and 2.4 ± 0.8 to 2.6 ± 0.9 L·min for the standardized and individualized groups, respectively. A significant difference in responsiveness was found between the individualized and standardized groups with 100% and 60% of participants categorized as responders, respectively. CONCLUSIONS: A threshold model for exercise intensity prescription had a greater effect on the incidence of CRF training response compared with a standardized approach using heart rate reserve. The use of thresholds for intensity markers accounts for individual metabolic characteristics and should be considered as a viable and practical method to prescribe exercise intensity.

Changes in Metabolic Syndrome Severity Following Individualized Versus Standardized Exercise Prescription: A Feasibility Study.

This study sought to investigate the efficacy of standardized versus individualized exercise intensity prescription on metabolic syndrome (MetS) severity following a 12-week exercise intervention. A total of 38 experimental participants (47.8 ± 12.2 yr, 170.7 ± 8.0 cm, 82.6 ± 18.7 kg, 26.9 ± 6.7 mL·k-1·min-1) were randomized to one of two exercise interventions (exercise intensity prescribed using heart rate reserve or ventilatory threshold). Following the 12-week intervention, MetS z-score was significantly improved for the standardized (-2.0 ± 3.1 to -2.8 ± 2.8 [p = 0.01]) and individualized (-3.3 ± 2.3 to -3.9 ± 2.2 [p = 0.04]) groups. When separating participants based on prevalence of MetS at baseline and MetS z-score responsiveness, there were six and three participants in the standardized and individualized groups, respectively, with three or more MetS risk factors. Of the six participants in the standardized group, 83% (5/6) of the participants were considered responders, whereas 100% (3/3) of the individualized participants were responders. Furthermore, only 17% (1/6) of the participants with MetS at baseline in the standardized group no longer had symptoms of MetS following the intervention. In the individualized group, 67% (2/3) of participants with baseline MetS were not considered to have MetS at week 12. These findings suggest that an individualized approach to the exercise intensity prescription may ameliorate the severity of MetS.

High-Intensity Interval Training Is Equivalent to Moderate-Intensity Continuous Training for Short- and Medium-Term Outcomes of Glucose Control, Cardiometabolic Risk, and Microvascular Complication Markers in Men With Type 2 Diabetes.

We sought to determine the efficacy of 12 weeks high-intensity interval training (HIIT), compared to moderate-intensity continuous training (MICT) on glucose control, cardiometabolic risk and microvascular complication markers in men living with type 2 diabetes (T2D). Both modalities were combined with resistance training (RT). Additionally, the study aimed to determine the medium-term durability of effects. After a 12-week, thrice weekly, training intervention incorporating either MICT+RT (n = 11) or HIIT+RT (n = 12), the study concluded with a 6-month follow-up analysis. The middle-aged study participants were obese, had moderate duration T2D and were taking multiple medications including insulin, statins and beta-blockers. Participants, randomized via the method of minimization, performed MICT (progressing to 26-min at 55% maximum estimated workload [eWLmax]) or HIIT (progressing to two variations in which twelve 1-min bouts at 95% eWLmax interspersed with 1-min recovery bouts, alternated with eight 30-s bouts at 120% eWLmax interspersed with 2:15 min recovery bouts) under supervision at an exercise physiology facility. To account for fixed and random effects within the study sample, mixed-effect models were used to determine the significance of change following the intervention and follow-up phases and to evaluate group*time interactions. Beyond improvements in aerobic capacity (P < 0.001) for both groups, both training modalities elicited similar group*time interactions (P > 0.05) while experiencing benefits for glycated hemoglobin (HbA1c; P = 0.01), subcutaneous adiposity (P < 0.001), and heart rate variability (P = 0.02) during the 12-week intervention. Adiposity (P < 0.001) and aerobic capacity (P < 0.001) were significantly maintained in both groups at the 6-month follow-up. In addition, during the intervention, participants in both MICT+RT and HIIT+RT experienced favorable reductions in their medication usage. The study reported the inter-individual variability of change within both groups, the exaggerated acute physiological responses (using exercise termination indicators) that occurred during the interventions as well as the incidence of precautionary respite afforded in such a study sample. To reduce hyperglycaemia, and prevent further deterioration of cardiometabolic risk and microvascular complication markers (in both the short- and medium-term), future strategies that integrate the adoption and maintenance of physical activity as a cornerstone in the treatment of T2M for men should (cognisant of appropriate supervision) include either structured MICT+RT, or HIIT+RT. Clinical Trials Registration Number: ACTRN12617000582358 http://www.anzctr.org.au/default.aspx.

Using a site-specific technical error to establish training responsiveness: a preliminary explorative study.

BACKGROUND: Even though cardiorespiratory fitness (CRF) training elicits numerous health benefits, not all individuals have positive training responses following a structured CRF intervention. It has been suggested that the technical error (TE), a combination of biological variability and measurement error, should be used to establish specific training responsiveness criteria to gain further insight on the effectiveness of the training program. To date, most training interventions use an absolute change or a TE from previous findings, which do not take into consideration the training site and equipment used to establish training outcomes or the specific cohort being evaluated. The purpose of this investigation was to retrospectively analyze training responsiveness of two CRF training interventions using two common criteria and a site-specific TE. METHODS: Sixteen men and women completed two maximal graded exercise tests and verification bouts to identify maximal oxygen consumption (VO2max) and establish a site-specific TE. The TE was then used to retrospectively analyze training responsiveness in comparison to commonly used criteria: percent change of >0% and >+5.6% in VO2max. RESULTS: The TE was found to be 7.7% for relative VO2 max. χ2 testing showed significant differences in all training criteria for each intervention and pooled data from both interventions, except between %Δ >0 and %Δ >+7.7% in one of the investigations. Training nonresponsiveness ranged from 11.5% to 34.6%. CONCLUSION: Findings from the present study support the utility of site-specific TE criterion to quantify training responsiveness. A similar methodology of establishing a site-specific and even cohort specific TE should be considered to establish when true cardiorespiratory training adaptations occur.

A comparison of the acute physiological responses to BODYPUMP™ versus iso-caloric and iso-time steady state cycling.

OBJECTIVES: Given apparent consumer interest in calorie counting and arguably inadequate understanding of the differential effects of exercise modality despite equivalent caloric expenditure, we sought to quantify and compare the acute physiological responses within and between a BODYPUMP™ (BP) group-fitness class and steady-state cycling (CARDIO), matched for caloric cost (iso-caloric) and time (iso-time). DESIGN: Acute cross-over study design. METHODS: Twelve healthy recreationally active females (30.1±5.8 years [mean±SD]) completed cardiorespiratory fitness and strength tests. Subsequently, BP and CARDIO were performed on separate days in randomized order, during which heart rate was monitored continuously, and rating of perceived exertion solicited. Blood samples were collected immediately pre- and post-trial and at 45min post-trial for determination of human growth hormone (HGH), interleukin 6 (IL-6), and cortisol. Lactate (BL) was determined from capillary blood. All outcome measures were analyzed for within-, and between-trial differences. RESULTS: HGH, IL-6 and BL were significantly elevated immediately post-trial for both BP and cycling; the elevation for HGH and BL was significantly greater for BP than CARDIO. IL6 remained elevated at 45min post-trial for both exercise modes, but there was no significant between trial difference. Mean heart rate for both trials was 68% of individually determined maximum heart rate, and predicted VO2 during BP was 14.9±5.2mlkgmin, or 46.7±19.4%VO2peak. Mean load self-selected by participants during BP ranged from 21±7%1RM to 32±9%1RM across four exercises. CONCLUSIONS: These results indicate that BP provided some more potent acute physiological effects than iso-caloric and iso-time steady-state cycling.

Acute blood glucose, cardiovascular and exaggerated responses to HIIT and moderate-intensity continuous training in men with type 2 diabetes mellitus.

BACKGROUND: Optimizing exercise-induced physiological responses without increasing the risk of negative exaggerated responses is an important aspect of exercise prescription for people with type 2 diabetes mellitus (T2DM). However, knowledge of acute responses, including exaggerated responses, of different training modalities is limited. The aim of the study was to compare acute physiological responses of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) in T2DM. METHODS: Baseline data were used to randomly assign male participants into supervised training groups for a 12-week intervention. During week 7, participants trialed either a fully progressed MICT (N.=11) or HIIT (N.=11) (combined with resistance training) session. The MICT included 26 minutes at 55% estimated maximum workload (eWLmax) while the HIIT included twelve 1-minute bouts at 95% eWLmax interspersed with 1-minute bouts at 40% eWLmax. RESULTS: While energy expenditure and peak systolic and diastolic blood pressure responses were similar between groups (P=0.47, P=0.71, P=0.56, respectively), peak heart rate, workload and perceived exertion were higher in the HIIT group (P=0.04, P<0.001, and P<0.001, respectively). Acute exaggerated responses were similar (P=0.39) for MICT (64%) and HIIT (36%) participants. CONCLUSIONS: While structured MICT and HIIT sessions resulted in comparable acute physiological responses, the individual variations and exaggerated responses, even after preparatory training, necessitated precautionary respite in T2DM men.

Exploring the impact of high intensity interval training on adolescents' objectively measured physical activity: Findings from a randomized controlled trial.

High Intensity Interval Training (HIIT) may be effective for accumulating VPA. However, the contribution of HIIT to overall physical activity is unknown. Our primary aim was to explore the impact of school-based HIIT on physical activity. The secondary aim was to explore within-individual changes in physical activity after participating in HIIT. Participants [n = 65; 15.8(0.6)years] were randomized to a HIIT or control group. Intervention groups participated in three HIIT sessions/week. GENEActiv accelerometers assessed objective physical activity at baseline and week-one, to detect changes in MPA and VPA. Intervention effects were examined using linear mixed models and evidence of a change in physical activity (i.e., compensation) were examined using multilevel linear regression models. The group-by-time interaction effects for MPA and VPA were small and moderate, respectively. Adjusted difference between groups for VPA was 1.70 min/day, 95%CI -1.96 to 5.36; p = 0.354; d = 0.55). Embedding HIIT within the school-day had a moderate effect on VPA compared to controls. Compensation analyses (i.e., individual level) suggested that adolescents were more active on days when they participated in HIIT. Further studies are needed to test the effects of HIIT on adolescents' physical activity over extended time periods.

Home Testing of a Digital Prompter for People with Dementia.

This technology evaluation study assessed a personalised digital prompter designed for people with dementia, by trialling its use in the home by people with dementia and their carers. Technology based prompting may be used to support people with dementia to complete multi-step tasks in the home, provided that suitable tasks can be chosen and that a carer is able to load appropriate task steps onto the prompter. A prompter was developed specifically for this purpose, along with a detailed guidance manual. Twelve participants with mild or moderate dementia carried out cognitive tests and their carers completed carer burden and carer competence scales. Each pair attended a training session with a researcher and were provided with the prompter and instruction manual. The prompter was trialled at home for four weeks after a one-week familiarisation period, for use with a simple set task and one or two tasks chosen by the participants. Semi-structured interviews were used to capture the views of the participants at the start and end of the home testing, and to set and evaluate goals. Chosen tasks included preparing simple food and drinks, and using home appliances including coffee machines and television remote controls. There was a weak correlation between greater goal success for the participants and the carer goal success, number letter switching within the D-KEFS and ACE-III score. A thematic analysis of the interviews revealed three core themes relating to familiarity with technology, utility of the prompter and the cost versus benefit in terms of the effort required to set up the prompter. Factors influencing success could be grouped into: participants' motivation and capability; the design of the prompter; and the details of the task being carried out. Barriers to success included the difficulty of choosing a suitable task and the effort required to break down a task in to appropriate steps. All of the participants with dementia could follow the steps on the prompter, and all of the carers were able to choose, breakdown and load at least one task onto the prompter during the training session, but successful use in the home was varied because of the increased complexity of the home context. Changes to the hardware, software and manual were made in response to the data gathered during the study, in readiness for the planned further testing.