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Objectives The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors. Design Pilot randomised-controlled trial. Methods Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated. Results All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease. Conclusions This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials.

This study sought to describe middle cerebral artery blood flow velocity (MCAv) during a 4 km cycling time trial, and relate it to different pacing strategies adopted by participants. After familiarisation and a standardised exercise protocol, 15 male trained cyclists rode a 4 km time trial on a cycling ergometer. MCAv was assessed via transcranial Doppler ultrasound in the right hemisphere at resting baseline, and throughout the time trial. Mean arterial pressure, end-tidal partial pressure of carbon dioxide (PetCO2) and heart rate were assessed alongside MCAv. Plasma lactate was assessed post time trial. Data were compared depending upon whether participants completed the time trial with a positive (first half faster than the last) or negative pacing profile although there was no difference in the time to completion with either pacing strategy (positive 344 ± 23 s, negative 334 ± 14 s; p = 0.394). Lower mean MCAv (positive pacing −7.6 ± 14.2%, negative pacing +21.2 ± 15.0% compared to resting baseline measures; p = 0.004) and lower PetCO2 (significant interaction p

Objectives This study assessed the accuracy of two questionnaires for measuring the duration of physical activity (PA) by intensity compared to an objective measure in older adults. Design Cross-sectional observation Methods A total of 169 (female = 43.8%) participants aged 73–78 years (mean: 75.1 y; SD: 1.3) wore a SenseWear™ Armband (SWA) for seven-days and reported the duration of PA by intensity with a Physical Activity Recall (PAR) questionnaire and the Active Australia Survey (AAS). In addition, the duration of moderate-to-vigorous-PA (MVPA) and overall active time, weighted for intensity (Total PA; MET: min/week) was assessed. Univariate general linear models were used to compare the questionnaire and SWA measures of PA while controlling for age, sex and education. Results The PAR was associated with SWA moderate intensity PA (b = 0.19; 95% CI 0.03–0.35), MVPA (b = 0.19; 95% CI 0.02–0.37) and Total PA (b = 0.33; 95% CI 0.11–0.55). Although significant correlations were present, the models explained a small proportion of the variance in the SWA variables. The AAS was not associated with the SWA for any PA outcome. There was also significant under-reporting of PA duration for both questionnaires in comparison to the SWA. Conclusions The PAR questionnaire may be suitable for determining the effect of greater levels of PA on health outcomes. However, neither questionnaire can be considered valid in determining the duration of PA divided by intensity. In addition, questionnaire and objectively measured PA are not equivalent and absolute measures of PA derived from questionnaires should be interpreted with caution.

Given the importance of body composition in maintaining optimal physical and functional capacities, the use of appropriate, field-based assessment tools should be a priority to assist in maintaining the occupational safety of firefighters and the community. For ease, body mass index has often been used to assess these changes. However, it is limited in its accuracy. The purposes of this study were twofold: (a) to compare the validity of different measures of body composition against dual-energy X-ray absorptiometry (DXA) in urban firefighters and (b) to assess these measures in their ability to provide meaningful interpretation of criteria-driven categories of adiposity. A total of 64 male firefighters (age = 44.0 ± 9.5 years) underwent full anthropometric profiling (predictor equations used to determine body fat percentage [BF%]), bioelectrical impedance analysis (BIA), and DXA assessments. Participants’ body mass index was calculated, and BF% and lean mass were determined along with criteria-driven categorizations of adiposity. Anthropometric (skinfolds) predictor equations (e.g., mean bias = −4.4% for BF%) were typically closer to DXA measures, compared with BIA (9.4% for BF%). However, when determining categories of criteria-driven adiposity, BIA (42.9% overweight or obese) provided closer estimates to the DXA-determined distribution (44.6%) than anthropometric-based measures (up to 40%). Body mass index appears an inappropriate measure for accurately determining categories of adiposity with 64.1% classified as overweight or obese. Given the logistical constraints of anthropometric profiling, and the closeness of BIA to DXA in adiposity categories, BIA may be a suitable alternative to DXA for assessing body composition in professional urban firefighters.

Background: Falls are of great concern to older adults and costly to the health system. In addition the relationship between falls risk and falls risk predictor characteristics is complex. Objective: This study aimed to explore the relationship between two objective fall-risk measures tools, the Physiological Profile Assessment and the Berg Balance Scale and to determine how an individual’s sex, level of physical function, health-related and body composition characteristics impact these objective falls risk measures. Design: A cross-sectional, observational study. Participants: 245 community-dwelling older adults (M age=68.12 years, SD=6.21; 69.8% female). Measurements: Participants were assessed for falls-risk (Physiological Profile Assessment and the Berg Balance Scale), physical activity, physical functional and body composition characteristics. Pearson product-moment correlation coefficients were calculated to examine bivariate relationships and hierarchical multiple linear regression modelling was used to estimate the contribution of each predictor in explaining variance in falls-risk. Results: In females, there was a weak association between the two objective falls-risk measures (r =-0.17 p

This study aimed to describe the effect of compression garments on middle cerebral artery blood flow velocity (MCAv) in relation to cognitive and exercise performance whilst cycling. In a randomised-controlled-cross-over design, 15 well-trained male cyclists were recruited to participate in three identical trials wearing loose fitting shorts (control), low-grade, or medium-grade compression garments. The protocol involved four 8 min increments of cycling at 30%, 50%, 70%, and 85% maximal power output and a 4 km time-trial. Participants undertook a cognitive Stroop task at baseline and at the midpoint of each increment. MCAv was monitored with Transcranial Doppler Ultrasonography. Mean arterial pressure (MAP) and partial pressure of end-tidal CO2 (PetCO2) were measured throughout. MCAv, MAP, PetCO2, and reaction time of the complex Stroop task were influenced by exercise intensity, but not compression garments. Compression garments significantly affected cognitive accuracy in the complex Stroop tas...

Objectives Moderate intensity aerobic exercise is known to facilitate cognitive performance but new technologies enable increasing opportunities to investigate this phenomenon under different circumstances. This study aimed to describe the effect of exercise on executive function assessed though a novel tablet-based test. Design Twenty healthy, active participants volunteered to take part in the randomised fully controlled trial. Methods Participants undertook an initial test of maximal aerobic capacity as well as ventilatory threshold during an incremental cycle test. A touch screen tablet computer was placed in the middle of the handlebars at an angle of approximately 45°, and participants were asked to complete the response-inhibition cognitive task (Speed Match, Lumos Labs Inc.) at set time points. A full familiarisation trial was performed prior to subsequent visits, in which participants completed either the control (no exercise) and exercise (90% ventilatory threshold (VT)) trials in a randomised order. During the 1 h trials, the cognitive task was performed prior to, during and post the intervention. Reaction time and accuracy of participant responses were recorded. Results Performing the cognitive task resulted in elevated heart rates and ventilation rates during control and exercise. Exercise facilitated performance in the executive function task such that reaction time was enhanced with no change in accuracy. A range of reliability measures are also reported. Conclusions This method of assessing executive function during exercise displays face validity and provides promise for further investigation of cognitive function using a simple, short duration, easily administered and widely available test.

We sought to explore the relationship between two subjective falls-risk assessment tools (Falls Efficacy Scale–International [FES-I] and Activities-Specific Balance Confidence [ABC] Scale) and functional, health-related, and body composition characteristics. A total of 245 community-dwelling people aged 60 to 88 years underwent assessments for subjective falls risk (using the FES-I and ABC Scale), health-related (cognitive; Short-Form Health Survey [SF-12]), functional (physical activity and physical function), and body composition characteristics (measured by dual X-ray absorptiometry). The FES-I and ABC Scale are strongly correlated with each other for females and males ( r = −.70, p < .001; r = −.65, p < .001), respectively. There are substantial differences between males and females when they self-assess their risk of falling as well as what characteristics contribute to explaining these self-assessments. Females are potentially more self-aware of their functional, body composition and health-related characteristics to better estimate their own risk of falling. FES-I correlates better with functional, body composition, and health-related characteristics, and thus may be more appropriate for use than the ABC in community-dwelling older adults.

Purpose:Nitrate supplementation improves endurance exercise and single bouts of high-intensity activity, but its effect on repeated sprints is unclear. This study is the first to investigate the effects of acute dietary nitrate supplementation during a high-intensity intermittent-sprint test to exhaustion.Methods:Team-sport athletes (9 male, age 22.3 ± 2.1 y, VO2max 57.4 ± 8.5 mL · kg−1 · min−1; 7 female, age 20.7 ± 1.3 y, VO2max 47.2 ± 8.5 mL · kg−1 · min−1) were assigned to a double-blind, randomized, crossover design. Participants consumed 70 mL of concentrated beetroot juice containing a minimum of 0.3 g of nitrate (NT) or 70 mL of placebo (PL) 2 h before a repeated-sprint protocol involving repeated 8-s sprints with 30-s recovery on a cycle ergometer to exhaustion.Results:Fewer sprints (NT = 13 ± 5 vs PL = 15 ± 6, P = .005, d = 0.41) and less total work (NT = 49.2 ± 24.2 kJ vs PL = 57.8 ± 34.0 kJ, P = .027, d = 0.3) were completed in NT relative to PL. However there was no difference in overall mean power output or the mean power output for each individual 8-s sprint.Conclusions:These findings suggest that dietary nitrate is not beneficial for improving repeated-sprint performance, at least when such sprints are near-maximal and frequent in nature. The lack of an effect of nitrate at near-maximal oxygen uptake supports the suggestion that at greater exercise intensities nitrate does not have an ergogenic effect.