Association between physical fitness and executive functions in cognitively healthy female older adults: a cross-sectional study.

Cardiovascular endurance and muscular fitness seem to impact specific cognitive components in older females. However, it remains uncertain whether these relate to executive functions or if these correlations are limited to specific physical fitness indicators. This study aimed to determine the association between specific physical fitness components and executive functions in community-dwelling older females. Thirty-five cognitively healthy community-dwelling older females (71.5 ± 5.7 years) underwent a series of physical fitness tests. These included the handgrip strength test (HGT), the 6-min walk test (6MWT), the 8-foot up-and-go test (8FUGT), and the chair stand test (CST). Participants also completed trail A and trail B of the cognitive trail making test. Results showed that trail B reaction time had a negative association with both HGT (r = - 0.502; p = 0.002) and 6MWT (r = - 0.543; p < 0.001). Together, the HGT and 6MWT results explained 39% of the variation in trail B reaction times: HGT accounted for 18% and 6MWT for 21%. Better scores on the 6MWT and HGT-but not on the 8FUGT and CST-correlated with enhanced executive function in cognitively healthy community-dwelling older females. The results of this study underscore the importance of specific physical assessments, like the 6MWT and HGT, as potential indicators of executive function, offering targeted strategies for maintaining cognitive health in aging females.

The Relation Between Frailty and Hypertension is Partially Mediated by Physical Activity Among Males and Females in the Canadian Longitudinal Study on Aging.

Frailty reflects the heterogeneity in aging and may lead to the development of hypertension and heart disease, but the frailty-cardiovascular relation and whether physical activity modifies this relation in males and females is unclear. We tested if higher frailty was positively associated with hypertension and heart disease in males and females, and if habitual movement mediated this relation. The relation between baseline frailty with follow-up hypertension and heart disease was investigated using the Canadian Longitudinal Study on Aging at 3-year Follow-Up data (males: n=13095, females: n=13601). Frailty at baseline was determined via a 73-item deficit-based index, activity at follow-up via the Physical Activity Scale for the Elderly, and cardiovascular function was self-reported. Higher baseline frailty level was associated with a greater likelihood of hypertension and heart disease at follow-up, with covariate-adjusted odds ratios of 1.08-1.09 (all, p<0.001) for a 0.01 increase in frailty index score. Among males and females, sitting time and strenuous physical activity were independently associated with hypertension, with these activity behaviours being partial mediators (except males-sitting time) for the frailty-hypertension relation (explained 5-10% of relation). The strength of this relation was stronger among females. Only light-moderate activity partially mediated the relation (~6%) between frailty and heart disease in females, but no activity measure was a mediator for males. Higher frailty levels were associated with a greater incidence of hypertension and heart disease, and strategies that target increases in physical activity and reducing sitting may partially uncouple this relation with hypertension, particularly among females.

A Single Bout of Prolonged Sitting Augments Very Short-Term Blood Pressure Variability.

BACKGROUND: More habitual time spent engaging in prolonged sedentary behaviours increases the risk of developing hypertension. Beat-by-beat systolic (SBPV) and diastolic blood pressure variability (DBPV) are more pronounced in persons with hypertension and may be an early manifestation of blood pressure dysregulation. We tested the hypothesis that a single bout of prolonged sitting augments very short-term SBPV and DBPV. The secondary aim was to explore sex differences in prolonged sitting-induced increases in SBPV and DBPV. METHODS: Thirty-three adults (22.9±1.9 years; 17 females) completed a single, 3-hr bout of prolonged sitting with beat-by-beat arterial pressure determined at baseline, 1.5-hr, and 3-hr via finger photoplethysmography. RESULTS: There were no sex differences observed for baseline brachial SBP (males: 122±10 mmHg; females: 111±9 mmHg), SBPV (males: 1.87±0.63 mmHg; females: 1.51±0.38 mmHg), DBP (males: 68±6 mmHg; females: 66±8 mmHg), or DBPV (males: 1.40±0.41 mmHg; females: 1.27±0.32 mmHg) (all, p>0.41). In the pooled sample, baseline SBPV (1.68±0.54 mmHg) remained unchanged after 1.5-hr (1.80±0.60 mmHg; p=0.59), but increased after 3.0-hr (1.84±0.52 mmHg; p=0.01). This post-sitting increase was driven by males (p=0.009), with no difference observed in females (p=1.00). Similarly, baseline DBPV (1.33±0.36 mmHg) was similar after 1.5-hr (1.42±0.41 mmHg; p=0.72) but was increased at 3-hr (1.50±0.34 mmHg; p=0.02). However, no sex differences in DBPV (all, p>0.07) were observed across the time points. CONCLUSIONS: In young, normotensive adults, a single bout of prolonged sitting augmented beat-by-beat blood pressure variability, which may provide a link between uninterrupted sitting and the development of blood pressure dysregulation.

Effectiveness of contrast-enhanced duplex ultrasound for detecting renal artery stenosis: A systematic review.

PURPOSE: Contrast-enhanced duplex ultrasound (CEUS) might be a useful tool to diagnosing renal artery stenosis (RAS). We amalgamated and reviewed the evidence assessing the diagnostic accuracy of CEUS on detecting RAS compared to angiography. METHODS: This preregistered systematic review included studies that compared the presence of RAS via CEUS with angiography. Sources were searched in November 2022 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier (n = 1717). The Quality Assessment of Diagnostic Studies 2 tool assessed study quality. Results are presented narratively. RESULTS: The studies included (n = 11) had a total of 447 unique participants (193 females) and average age of 56 ± 9 years. Five of eleven studies investigated CEUS using SonoVue contrast agent and reported an average accuracy (91% ± 2%), sensitivity (91% ± 3%), specificity (90% ± 5%), negative predictive value (86% ± 6%), and positive predictive value (94% ± 1%) with all values >80%. The accuracy of CEUS using other types of contrast agent (n = 6), including Levovsit (n = 3/6), Definity (n = 1/6), perfienapent emulsion (n = 1/6), and perfluorocarbon-exposed sonicated dextrose albumin (n = 1/6) was mixed. These studies detected an average accuracy of 91 ± 11% (n = 2/3% > 80%), sensitivity of 98% ± 4%, (n = 3/3% > 80%), and specificity of 86% ± 10% (n = 2/3% > 80%). Included studies had generally low risk of bias and applicability concerns except for unclear flow and timing (n = 7/11) and applicability of patient selection (n = 4/11). CONCLUSION: Despite being limited by the heterogeneity of included studies, our review indicates a high overall diagnostic accuracy for CEUS to detect RAS compared to angiography, with the largest evidence-base for SonoVue contrast. Radiologists and hospital decision makers should consider CEUS as an acceptable alternative to angiography.

Sitting knee-flexion angle does not influence endothelial-dependent vasodilation in laboratory or free-living conditions.

INTRODUCTION: Single bouts of prolonged bent-legged sitting attenuate popliteal endothelial-dependent vasodilation (as assessed via flow-mediated dilation [FMD]), which is partially attributed to arterial 'kinking'. However, the impact of knee-flexion angle on sitting-induced popliteal FMD is unknown. The objective of this study was to perform separate laboratory and free-living studies to test the hypotheses that: (1) popliteal FMD impairments would be graded between knee flexions at 90° (bent-legged sitting) > 45° > 0° (straight-legged sitting) following a 3-hour bout of sitting; and (2) more habitual time spent bent-legged sitting (< 45°) would be associated with lower FMD. METHODS: The laboratory study included eight young, healthy adults (24 ± 2 years; four women) who underwent two sitting bouts over 2 days with one leg positioned at a knee-flexion angle of 0° or 90° and the opposite leg at 45° knee flexion. Popliteal FMD was assessed at pre- and postsitting timepoints. RESULTS: Sitting-induced reductions in FMD were similar between all knee-flexion angles (all, p > 0.674). The free-living study included 35 young, healthy adults (23 ± 3 years; 16 women) who wore three activPAL monitors (torso, thigh, shin) to determine detailed sedentary postures. Time spent sedentary (624 ± 127 min/day), straight-legged sitting (112 ± 98 min/day), and bent-legged sitting (442 ± 106 min/day) were not related to relative FMD (5.3 ± 1.8%; all, p > 0.240). CONCLUSION: These findings suggest that knee-flexion angle-mediated arterial 'kinking' during sitting is not a major contributor toward sitting-induced popliteal endothelial-dependent vasodilatory dysfunction.

Association between changes in habitual stepping activity and cognition in older adults.

Advancing age is associated with declines in cognitive function. Although physical activity is thought to protect against this decline, it is unclear how a short-term uptake in daily steps or a decline in day-to-day step variability may contribute to cognition among older adults. We tested associations between changes in step counts, day-to-day step variability and executive cognitive functions among older adults taking part in a physical activity intervention. Thirty-seven older adults (33 females; 71.4 ± 6.3 years) completed a 10-week personalized physical activity intervention. Participants wore a Fitbit to measure daily step counts throughout the study. They also completed a computerized Stroop task before and after the intervention. Average step counts and step count variability via average-real-variability (ARV) were determined. Compared to pre-intervention, step counts increased (p < 0.001) and step variability decreased post-intervention (p = 0.04). Models describing the changes in step counts and ARV over the 10-weeks were cubic (both, p < 0.04). Reaction times during the simple (p = 0.002) and switching (p = 0.04) conditions were faster post-intervention. Change in step variability was positively associated with the change in reaction time for the switching condition (ß = 0.029, p = 0.002). On average, a reduction in day-to-day step variability was associated with improvements in cognitive flexibility.

Faster stepping cadence partially explains the higher metabolic cost of walking among females versus males.

The metabolic cost of walking (MCOW), or oxygen uptake normalized to distance, provides information on the energy expended during movement. There are conflicting reports as to whether sex differences in MCOW exist, with scarce evidence investigating factors that explain potential sex differences. This study 1) tested the hypothesis that females exhibit a higher MCOW than males, 2) determined whether normalizing to stepping cadence ameliorates the hypothesized sex difference, and 3) explored whether more habitual step counts and time in intensity-related physical activity, and less sedentary time were associated with a decreased MCOW. Seventy-six participants (42 females, 24 ± 5 yr) completed a five-stage, graded treadmill protocol with speeds increasing from 0.89 to 1.79 m/s (6-min walking stage followed by 4-min passive rest). Steady-state oxygen uptake (via indirect calorimetry) and stepping cadence (via manual counts) were determined. Gross and net MCOW, normalized to distance traveled (km) and step-cadence (1,000 steps) were calculated for each stage. Thirty-nine participants (23 females) wore an activPAL on their thigh for 6.9 ± 0.4 days. Normalized to distance, females had greater gross MCOW (J/kg/km) at all speeds (P < 0.014). Normalized to stepping frequency, females exhibited greater gross and net MCOW at 1.12 and 1.79 m/s (J/kg/1,000 steps; P < 0.01) but not at any other speeds (P < 0.075). Stature was negatively associated with free-living cadence (r = -0.347, P = 0.030). Females expend more energy/kilometer traveled than males, but normalizing to stepping cadence attenuated these differences. Such observations provide an explanation for prior work documenting higher MCOW among females and highlight the importance of stepping cadence when assessing the MCOW.NEW & NOTEWORTHY Whether there are sex differences in the metabolic cost of walking (MCOW) and the factors that may contribute to these are unclear. We demonstrate that females exhibit a larger net MCOW than males. These differences were largely attenuated when normalized to stepping cadence. Free-living activity was not associated with MCOW. We demonstrate that stepping cadence, but not free-living activity, partially explains the higher MCOW in females than males.

Sympathetic determinants of resting blood pressure in males and females.

Discharge of postganglionic muscle sympathetic nerve activity (MSNA) is related poorly to blood pressure (BP) in adults. Whether neural measurements beyond the prevailing level of MSNA can account for interindividual differences in BP remains unclear. The current study sought to evaluate the relative contributions of sympathetic-BP transduction and sympathetic baroreflex gain on resting BP in young adults. Data were analyzed from 191 (77 females) young adults (18-39 years) who underwent continuous measurement of beat-to-beat BP (finger photoplethysmography), heart rate (electrocardiography), and fibular nerve MSNA (microneurography). Linear regression analyses were computed to determine associations between sympathetic-BP transduction (signal-averaging) or sympathetic baroreflex gain (threshold technique) and resting BP, before and after controlling for age, body mass index, and MSNA burst frequency. K-mean clustering was used to explore sympathetic phenotypes of BP control and consequential influence on resting BP. Sympathetic-BP transduction was unrelated to BP in males or females (both R2 < 0.01; P > 0.67). Sympathetic baroreflex gain was positively associated with BP in males (R2 = 0.09, P < 0.01), but not in females (R2 < 0.01; P = 0.80), before and after controlling for age, body mass index, and MSNA burst frequency. K-means clustering identified a subset of participants with average resting MSNA, yet lower sympathetic-BP transduction and lower sympathetic baroreflex gain. This distinct subgroup presented with elevated BP in males (P < 0.02), but not in females (P = 0.10). Sympathetic-BP transduction is unrelated to resting BP, while the association between sympathetic baroreflex gain and resting BP in males reveals important sex differences in the sympathetic determination of resting BP.NEW & NOTEWORTHY In a sample of 191 normotensive young adults, we confirm that resting muscle sympathetic nerve activity is a poor predictor of resting blood pressure and now demonstrate that sympathetic baroreflex gain is associated with resting blood pressure in males but not females. In contrast, signal-averaged measures of sympathetic-blood pressure transduction are unrelated to resting blood pressure. These findings highlight sex differences in the neural regulation of blood pressure.

Frailty is associated with worse executive function and higher cerebral blood velocity in cognitively healthy older adults: a cross-sectional study.

Frailty is characterized by an increased vulnerability to adverse health events. Executive function impairment is an early sign of progression towards cognitive impairments. Whether frailty is associated with executive function and the associated mechanisms are unclear. We test the hypothesis that higher frailty is associated with worse executive function (Trail Making Test) and if aerobic fitness, prefrontal cortex oxygenation (ΔO2Hb), or middle-cerebral artery velocity (MCAv) impact this association. Forty-one (38 females) cognitively health older adults (70.1 ± 6.3 years) completed a Trail task and 6-min walk test. Prefrontal cortex oxygenation was measured during the Trail task (via functional near-infrared spectroscopy) and MCAv in a sub-sample (n=26, via transcranial Doppler). A 35-item frailty index was used. Frailty was independently, non-linearly related to trail B performance (Frailty2: ß=1927 [95% CI: 321-3533], p = 0.02), with the model explaining 22% of the variance of trail B time (p = 0.02). Aerobic fitness was an independent predictor of trail B (ß=-0.05 [95% CI: -0.10-0.004], p = 0.04), but age and ΔO2Hb were not (both, p > 0.78). Frailty was positively associated with the difference between trails B and A (ß=105 [95% CI: 24-186], p = 0.01). Frailty was also associated with a higher peak MCAv (ρ = 0.40, p = 0.04), but lower ΔO2Hb-peakMCAv ratio (ρ = -0.44, p = 0.02). Higher frailty levels are associated to worse Trail times after controlling for age, aerobic fitness, and prefrontal oxygenation. High frailty level may disproportionately predispose older adults to challenges performing executive function tasks that may manifest early as a compensatory higher MCAv despite worse executive function, and indicate a greater risk of progressing to cognitive impairment.

Impact of Hospitalization on Patients Ability to Perform Basic Activities of Daily Living.

Functional independence is dictated by the ability to perform basic activities of daily living (ADLs). Although hospitalization is associated with impairments in function, we know less about patients' functional trajectory following hospitalization. We examined patients' ability to do basic ADLs across pre-admission, admission, and follow-up (discharge or two-weeks post-admission) and determined which factors predicted changes in ADLs at follow-up. A secondary analysis of a small prospective cohort study of older patients (n=83, 50 females, 81 ± 8 years) from the Emergency Department and a Geriatric Unit were included. ADL scores (dressing, walking, bathing, eating, in and out of bed, and using the toilet) and frailty level (via the Clinical Frailty Scale) were measured. Comparing follow-up to pre-admission, patients reported worse ADL scores for dressing (36% of patients), walking (31%), bathing (34%), eating (25%), in and out of bed (37%), and using the toilet (35%). Most patients (59%) had more difficulty with 1+ ADL at follow-up versus pre-admission, with one-fourth of patients having greater difficulty with 3+ ADLs. Older age and higher frailty level were associated with (all, p < .04) worse functional scores for eating, getting in and out of bed, and using the toilet (frailty only) at follow-up versus pre-admission. Here, most inpatients experienced worse difficulty performing multiple basic ADLs after hospital admission, potentially predisposing them for re-hospitalization and functional dependence. Older and frailer patients generally were less likely to recover to pre-admission levels. Hospitalization challenges patients' ability to perform ADLs in the short-term, post-discharge. Strategies to improve patients' functional trajectory are needed.

Physical activity counselling and exercise prescription practices of chiropractors in Canada and internationally: an exploratory survey.

Background: Physical activity and exercise (PAE) counselling and exercise prescriptions increase patient physical activity. However, the perceptions/practices of chiropractors are poorly understood. Methods: We surveyed the practices among chiropractors working in Canada (n=50) and Internationally (n=37). Chiropractors completed self-reflection questionnaires regarding their current practices and perceptions towards providing PAE counselling to patients. Chiropractor responses were obtained via Canadian provincial survey and educational workshops. Results: Chiropractor respondents included PAE content and exercise prescriptions in most patient appointments (67±27% and 59±35%, respectively), but the largest barriers (2.5/4.0) and least confidence were in their patients to follow through (52±21%). Canadian respondents reported higher knowledge (~0.4/4.0 higher), greater self-confidence (10-20% higher), and provided more PAE recommendations (8%) and prescriptions (16%) than International respondents. Chiropractor respondents were least comfortable advising patients with cancer. Conclusion: Chiropractor respondents may serve as health promotors to address patient inactivity, and the challenges identified should be addressed through educational training.

Contexte: Les conseils en matière d'activité physique et d'exercice (APE) et les prescriptions d'exercices augmentent l'activité physique des patients. Cependant, les perceptions et les pratiques des chiropraticiens sont mal comprises. Méthodologie: Nous avons enquêté sur les pratiques des chiropraticiens travaillant au Canada (n=50) et à l'étranger (n=37). Les chiropraticiens ont rempli des questionnaires d'auto-réflexion sur leurs pratiques actuelles et leurs perceptions quant à l'offre de conseils aux patients en matière d'APE. Les réponses des chiropraticiens ont été obtenues au moyen d'une enquête provinciale canadienne et des ateliers éducatifs. Résultats: Les chiropraticiens interrogés ont inclus le contenu d'APE et les prescriptions d'exercices dans la plupart des rendez-vous avec les patients (67±27 % et 59±35 %, respectivement), mais les obstacles les plus importants (2,5/4,0) et la confiance la plus faible étaient à propos du fait que leurs patients allaient suivre les conseils (52±21 %). Les répondants canadiens ont fait état d'une meilleure connaissance (~0,4/4,0 de plus), d'une plus grande confiance en soi (10­20 % de plus) et ont fourni plus de recommandations (8 %) et de prescriptions (16 %) en matière d'APE que les répondants internationaux. Les chiropraticiens interrogés se sont montrés moins à l'aise pour conseiller les patients atteints de cancer. Conclusion: Les chiropraticiens interrogés peuvent servir de promoteurs de la santé pour lutter contre l'inactivité des patients, et les difficultés relevées devraient être abordées dans le cadre d'une formation.

Mechanistic, participant, and movement-related factors that contribute to low-flow-mediated constriction.

Endothelial function is commonly determined via the ultrasound-based flow-mediated dilation (FMD) technique which assesses arterial dilation in response to a hyperemia response following distal cuff occlusion. However, the low-flow-mediated constriction (L-FMC) response during cuff-induced ischemia is often overlooked. L-FMC provides unique information regarding endothelial function, but vascular researchers may be unclear on what this metric adds. Therefore, the objective of this review was to examine the mechanistic determinants and participant-level factors of L-FMC. Existing mechanistic studies have demonstrated that vasoreactivity to low flow may be mediated via non-nitric oxide vasodilators (i.e., endothelial hyperpolarizing factors and/or prostaglandins), inflammatory markers, and enhancement of vasoconstriction via endothelin-1. In general, participant-level factors such as aging and presence of cardiovascular conditions generally are associated with attenuated L-FMC responses. However, the influence of sex on L-FMC is unclear with divergent results between L-FMC in upper versus lower limb vessels. The ability of aerobic exercise to augment L-FMC (i.e., make more negative) is well supported, but there is a major gap in the literature concerning the mechanistic underpinnings of this observation. This review summarizes that while larger L-FMC responses are generally healthy, the impact of interventions to augment/attenuate L-FMC has not included mechanistic measures that would provide insight into non-nitric oxide-based endothelial function. Clarifications to terminology and areas of further inquiry as it relates to the specific pharmacological, individual-level factors, and lifestyle behaviors that impact L-FMC are highlighted. A greater integration of mechanistic work alongside applied lifestyle interventions is required to better understand endothelial cell function to reductions in local blood flow.

Interrupting bedtime to reverse frailty levels in acute care: a study protocol for the Breaking Bad Rest randomized controlled trial.

BACKGROUND: Hospitalized older patients spend most of the waking hours in bed, even if they can walk independently. Excessive bedrest contributes to the development of frailty and worse hospital outcomes. We describe the study protocol for the Breaking Bad Rest Study, a randomized clinical trial aimed to promoting more movement in acute care using a novel device-based approach that could mitigate the impact of too much bedrest on frailty. METHODS: Fifty patients in a geriatric unit will be randomized into an intervention or usual care control group. Both groups will be equipped with an activPAL (a measure of posture) and StepWatch (a measure of step counts) to wear throughout their entire hospital stay to capture their physical activity levels and posture. Frailty will be assessed via a multi-item questionnaire assessing health deficits at admission, weekly for the first month, then monthly thereafter, and at 1-month post-discharge. Secondary measures including geriatric assessments, cognitive function, falls, and hospital re-admissions will be assessed. Mixed models for repeated measures will determine whether daily activity differed between groups, changed over the course of their hospital stay, and impacted frailty levels. DISCUSSION: This randomized clinical trial will add to the evidence base on addressing frailty in older adults in acute care settings through a devices-based movement intervention. The findings of this trial may inform guidelines for limiting time spent sedentary or in bed during a patient's stay in geriatric units, with the intention of scaling up this study model to other acute care sites if successful. TRIAL REGISTRATION: The protocol has been registered at clinicaltrials.gov (identifier: NCT03682523).

Impact of exercise training on pulse wave velocity in healthy and clinical populations: a systematic review of systematic reviews.

Elevated pulse wave velocity (PWV) determined arterial stiffness is a prominent marker of cardiovascular disease (CVD) risk. Exercise training delays the progression of CVD, but existing reviews on the impact of training on PWV are conflicting. We synthesized the evidence on the effects of exercise training interventions on PWV. We searched Scopus, EMBASE, PubMed, CINAHL, and Academic Search Premier databases for systematic reviews including PWV, and examined the effects of exercise training on PWV. We screened 842 citations that resulted in 44 systematic reviews, including 22 meta-analyses [unique participants, n = 6,719 (3,390 females)]. Studies were conducted in general adults with/without disease(s) (n = 19, 8 meta-analyses), kidney disease (n = 9, 6 meta-analyses), increased CVD risk or CVD (n = 7, 5 meta-analyses), type 2 diabetes mellitus (n = 3, 2 meta-analyses), and other conditions (n = 6, 2 meta-analyses). In general adults, PWV was reduced by aerobic exercise (ß, -0.75 to -0.52 m/s) and low-to-moderate intensity resistance exercise training (ß, -0.34 m/s). Exercise training was beneficial for patients with kidney disease (ß, -1.13 to -0.56 m/s). Aerobic exercise improved PWV in adults with CVD or high CVD risk (ß, -0.70 to -0.42 m/s). Combined aerobic and resistance exercise training decreased carotid-femoral (CF) PWV in patients with CVD (ß, -1.15 m/s) and decreased brachial-ankle (BA) PWV in postmenopausal females (ß, -1.18 m/s). Neither aerobic nor combined training improved PWV in individuals with type 2 diabetes. The potential physiological mechanisms involved are discussed. Overall, the included systematic reviews and meta-analyses documented that exercise training was an effective strategy to improve PWV, but the optimal type of training varied between populations.

Impact of unilateral dual-brachial arteries on endothelial-dependent and endothelial-independent vasodilation: a case study.

TAKE HOME MESSAGE: Our case study indicated that a bifurcated brachial artery exhibited worse vasodilatory responses relative to an intact contralateral artery.

Convergent validity and inter-rater reliability of a lower-limb multimodal physical function assessment in community-dwelling older adults.

Introduction: Lower-limb physical function declines with age and contributes to a greater difficulty in performing activities of daily living. Existing assessments of lower-limb function assess one dimension of movement in isolation or are not time-efficient, which discourages their use in community and clinical settings. We aimed to address these limitations by assessing the inter-rater reliability and convergent validity of a new multimodal functional lower-limb assessment (FLA). Methods: FLA consists of five major functional movement tasks (rising from a chair, walking gait, stair ascending/descending, obstacle avoidance, and descending to a chair) performed consecutively. A total of 48 community-dwelling older adults (32 female participants; age: 71 ± 6 years) completed the FLA as well as timed up-and-go, 30-s sit-to-stand, and 6-min walk tests. Results: Slower FLA time was correlated with a slower timed up-and-go test (ρ = 0.70), less sit-to-stand repetitions (ρ = -0.65), and a shorter distance in the 6-min walk test (ρ = -0.69; all, p < 0.001). Assessments by two raters were not different (12.28 ± 3.86 s versus 12.29 ± 3.83 s, p = 0.98; inter-rater reliability ρ = 0.993, p < 0.001) and were statistically equivalent (via equivalence testing). Multiple regression and relative weights analyses demonstrated that FLA times were most predicted by the timed up-and-go performance [adjusted R 2 = 0.75; p < 0.001; raw weight 0.42 (95% CI: 0.27, 0.53)]. Discussion: Our findings document the high inter-rater reliability and moderate-strong convergent validity of the FLA. These findings warrant further investigation into the predictive validity of the FLA for its use as an assessment of lower-limb physical function among community-dwelling older adults.

Higher habitual lying time is inversely associated with vagal-related heart rate variability outcomes in younger adults.

Heart rate variability (HRV) is a well-established noninvasive marker of autonomic cardiac control. We test whether time spent sitting (negatively) versus lying (positively) influences vagal HRV outcomes. HRV (10 min supine electrocardiogram) and free-living postures (dual-accelerometer configuration, 7 days) were measured in 31 young healthy adults (15♀, age: 23 ± 3 years). Habitual lying (66 ± 61 min/day), but not sitting time (558 ± 109 min/day), total sedentary time (623 ± 132 min/day), nor step counts (10 752 ± 3200 steps/day; all, p > 0.090), was associated with root mean square of successive cardiac interval differences (ρ = -0.409, p = 0.022) and normalized high-frequency HRV (ρ = -0.361, p = 0.046). These findings document a paradoxical negative impact of waking lying time on cardioautonomic function. Take home message Using a multi-accelerometer configuration, we demonstrated that more habitual waking time lying, but not sitting or total sedentary time, was associated with worse vagally mediated cardiac control.

Binge drinking and smoking are associated with worse academic performance in Canadian undergraduate students.

OBJECTIVE: Test the hypothesis that smoking, fast-food consumption, and binge drinking were negatively associated with academic performance in Canadian undergraduate students. PARTICIPANTS: Undergraduate students across Canada [n = 411 (335♀) aged: 22 ± 4 years] completed a questionnaire regarding their lifestyle behaviors and academic grades. METHODS: Relationships between lifestyle behaviors and academic performance were assessed via covariate-adjusted multiple regressions. Mediation models were used to test whether significant relationships between smoking/fast-food and grades were explained by binge drinking. RESULTS: Smoking (ß= -4.00, p < .001) and binge drinking (ß= -1.98, p = .002) were independent predictors of grades (average: 84 ± 8%). Binge drinking partially mediated the relationships between smoking (indirect effect ß= -1.19, 95%CI [-2.49, -0.08] and fast-food consumption (indirect effect: ß= -.75, 95%CI [-1.20, -0.29]), with grades. CONCLUSIONS: These findings highlight the negative influence of binge drinking, smoking, and fast-food consumption on academic success, with binge drinking as a partial mediator of these relationships.

Validity of ActivPAL CREA software detection of sitting and lying during free-living conditions.

Objective. Approaches to differentiate sitting and lying are available within the default activPAL software from a single thigh-worn monitor. Dual-monitor methods use multiple monitors positioned on the thigh and torso to characterize sitting versus lying. We evaluated the validity between these two methods to measure waking, sitting, and lying time in free-living conditions. We also examined if the degree-threshold distinguishing sitting/lying for the dual-monitor (<30° and <45°) impacted results.Approach. Thirty-five young adults (24 ± 3 years, 16 females) wore an activPAL 24 h per day on their thigh and torso during free-living conditions (average: 6.8 ± 1.0 d, 239 total). Data were processed using the default activPAL software (thigh-only) or a custom MATLAB program (dual-monitor).Main results. The single-monitor recorded less lying time (59 ± 99 min d-1) and more sitting time (514 ± 203 min d-1) than the dual-monitor method regardless of 30° (lying: 85 ± 94 min d-1; sitting: 488 ± 166 min d-1) or 45° lying threshold (lying: 170 ± 142, sitting: 403 ± 164 min d-1; all,p< 0.001). The single monitor lying time was weakly correlated to the dual-monitor (30°:ρ= 0.25, 45°:ρ= 0.21; both,p< 0.001), whereas sitting was moderate-strong (30°:ρ= 0.76, 45°:ρ= 0.58; both,p< 0.001). However, the mean absolute error was 81 min d-1(30°) and 132 min d-1(45°) for both lying and sitting.Significance. The method of differentiating sitting/lying from a single thigh-worn activPAL records more sitting time and less lying time compared to a dual-monitor configuration (regardless of degree-threshold) that considered the position of the torso. A further refinement of algorithms or implementation of multiple-monitor methods may be needed for researchers to derive detailed sedentary positions.