123 results on '"Rattray B"'
Search Results
2. Writing as a Tool for Physicians and Physician Leaders
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Sacopulos, M, primary and Rattray, B, additional
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- 2022
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3. Short-term eccentric exercise in newly diagnosed type II diabetics: an exploratory study
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Rattray, B., Steele, J., Semple, S., Ramirez, R., and Abhayaratna, W. P.
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- 2014
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4. Antenatal magnesium sulfate and spontaneous intestinal perforation in infants less than 25 weeks gestation
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Rattray, B N, Kraus, D M, Drinker, L R, Goldberg, R N, Tanaka, D T, and Cotten, C M
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- 2014
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5. A General Stone-Gelfand Duality
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Lambek, J. and Rattray, B. A.
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- 1979
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6. Localization and Sheaf Reflectors
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Lambek, J. and Rattray, B. A.
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- 1975
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7. Localization at Injectives in Complete Categories
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Lambek, J. and Rattray, B. A.
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- 1973
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8. An Antipodal-Point, Orthogonal-Point Theorem
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Rattray, B. A.
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- 1954
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9. A Short-Term Intervention of High-Intensity Exercise and Anodal-tDCS on Motor Learning in Middle-Aged Adults: An RCT.
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Quinlan, C, Rattray, B, Pryor, D, Northey, JM, Coxon, J, Cherbuin, N, Andrews, SC, Quinlan, C, Rattray, B, Pryor, D, Northey, JM, Coxon, J, Cherbuin, N, and Andrews, SC
- Abstract
High-intensity exercise has enhanced motor learning in healthy young adults. Anodal-transcranial direct current stimulation (a-tDCS) may optimize these effects. This study aimed to determine the effects of a short-term high-intensity interval exercise intervention either with or without a-tDCS on the learning and retention of a novel motor task in middle-aged adults. Forty-two healthy middle-aged adults (age = 44.6 ± 6.3, female = 76%) were randomized into three groups: exercise and active a-tDCS, exercise and sham a-tDCS, and a non-exercise and sham a-tDCS control. Participants completed a baseline testing session, followed by three intervention sessions 48-h apart. The exercise groups completed 20-min of high-intensity exercise followed by a novel sequential visual isometric pinch task (SVIPT) while receiving 20-min of 1.5 mA a-tDCS, or sham tDCS. The control group completed 20-min of reading before receiving sham a-tDCS during the SVIPT. Learning was assessed by skill change within and between intervention sessions. Participants returned 5-7 days after the final intervention session and performed the SVIPT task to assess retention. All three groups showed evidence of learning on the SVIPT task. Neither group displayed enhanced overall learning or retention when compared to the control group. High-intensity exercise with or without a-tDCS did not improve learning or retention of a novel motor task in middle-aged adults. The methodological framework provides direction for future research to investigate the potential of differing exercise intensity effects on learning and retention.
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- 2021
10. Objectively measured physical activity is associated with dorsolateral prefrontal cortex volume in older adults
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Northey, JM, Rattray, B, Pumpa, KL, Pryor, DJ, Fraser, MA, Shaw, ME, Anstey, KJ, Cherbuin, N, Northey, JM, Rattray, B, Pumpa, KL, Pryor, DJ, Fraser, MA, Shaw, ME, Anstey, KJ, and Cherbuin, N
- Abstract
Background: Epidemiological studies suggest physical activity (PA) can slow or prevent both cognitive decline and age-related atrophy in frontal and hippocampal gray matter volumes. However, much of this evidence is based on self-reported measures of PA. Methods: PA was measured objectively with a SenseWear™ Armband to examine the cross-sectional associations between the duration of light, moderate and vigorous intensity PA with gray matter volume in the dorsolateral prefrontal cortex (DLPFC) and hippocampus in 167 (female: 43%) cognitively healthy older adults aged 73 to 78. Results: The duration of objective moderate to vigorous intensity physical activity (MVPA) was associated with a greater volume of the right DLPFC (β = 0.16; p = 0.04). In addition, objective moderate-intensity PA alone was also associated with greater volume of the left (β = 0.17; p = 0.03) and right (β = 0.19; p = 0.01) DLPFC after controlling for covariates and adjustment for multiple comparisons. In contrast, there were no significant associations between light- or vigorous-intensity PA and gray matter volumes (all p > 0.05). No associations between PA and cognitive performance were detected, and self-reported PA was not associated with any of the outcomes investigated. Conclusions: These findings suggest that an intensity-dependent relationship may exist, whereby a greater duration of MVPA, perhaps driven by moderate-intensity PA, is associated with preserved gray matter volume in frontal regions of the brain. Future research should investigate the mechanisms of this dose-effect and determine whether greater brain volumes associated with objective PA convey protective effects against cognitive decline.
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- 2020
11. Celecoxib in the treatment of haemophilic synovitis, target joints, and pain in adults and children with haemophilia
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RATTRAY, B., NUGENT, D. J., and YOUNG, G.
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- 2006
12. Rofecoxib as adjunctive therapy for haemophilic arthropathy
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RATTRAY, B., NUGENT, D. J., and YOUNG, G.
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- 2005
13. Can the intensity of physical activity be accurately measured in older adults using questionnaires?
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Northey, JM, Rattray, B, Pumpa, KL, Smee, DJ, Welvaert, M, Anstey, KJ, Cherbuin, N, Northey, JM, Rattray, B, Pumpa, KL, Smee, DJ, Welvaert, M, Anstey, KJ, and Cherbuin, N
- Abstract
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.
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- 2019
14. VALIDATION OF A FIELD BASED INCREMENTAL TEST FOR PERFORMANCE ASSESSMENT IN ORIENTEERS
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Roberts, A D., Rattray, B, Linaker, K L., Montgomery, P G., and Kusnanik, N W.
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- 2003
15. PHYSIOLOGICAL RESPONSES OF WELL-TRAINED CYCLISTS TO FIELD AND LABORATORY MOUNTAIN BIKE RACE SIMULATIONS
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Linaker, K L., Martin, D T., Lawton, E, Rattray, B, Kusnanik, N W., and Roberts, A D.
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- 2003
16. Physiological Demands of Playing Field Hockey Game at Sub Elite Players
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Kusnanik, N W, primary, Rahayu, Y S, additional, and Rattray, B, additional
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- 2018
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17. The brain of an elite athlete: Do physical training adaptations extend to the brain?
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Martin, K., primary, Staiano, W., additional, Menaspa, P., additional, Keegan, R., additional, Hennessey, T., additional, Marcora, S., additional, Halson, S., additional, Martin, D., additional, Thompson, K., additional, and Rattray, B., additional
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- 2015
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18. Antenatal Magnesium Sulfate and Spontaneous Intestinal Perforation in Infants Less Than 25 Weeks Gestation
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Rattray, B. N., primary, Kraus, D. M., additional, Drinker, L. R., additional, Goldberg, R. N., additional, Tanaka, D. T., additional, and Cotten, C. M., additional
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- 2015
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19. Current warm-up practices and the contemporary issues faced by elite swimming coaches
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McGowan, C., primary, Rattray, B., additional, Thompson, K., additional, Pyne, D., additional, and Raglin, J., additional
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- 2014
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20. Selection and design of mill liners.
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Powell M., third international symposium on comminution at the SME annual meeting St. Louis, Missouri 27-Mar-0629-Mar-06, Cleary P., Eriksson K.G., Radziszewski P., Rattray B., Schaeffer L., Smit I., Powell M., third international symposium on comminution at the SME annual meeting St. Louis, Missouri 27-Mar-0629-Mar-06, Cleary P., Eriksson K.G., Radziszewski P., Rattray B., Schaeffer L., and Smit I.
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An overview is given of the main types and materials of liner contruction, focusing on a design basis of the best available technology combined with experience and logical engineering practice. Methods are presented for monitoring liner wear and its relation to mill performance, so that performance may be optimised and costs saved by balancing the longevity of the lifters and shell plates and by providing reliable comparative data for testing different liner materials and designs. The contribution of advanced computation techniques, such as the discrete element method, to profile wear prediction and the integration of the information into optimising overall performance is considered in some detail, taking into account the change of charge trajectories, energy transfer and grinding efficiency as the liner wears and the profile changes., An overview is given of the main types and materials of liner contruction, focusing on a design basis of the best available technology combined with experience and logical engineering practice. Methods are presented for monitoring liner wear and its relation to mill performance, so that performance may be optimised and costs saved by balancing the longevity of the lifters and shell plates and by providing reliable comparative data for testing different liner materials and designs. The contribution of advanced computation techniques, such as the discrete element method, to profile wear prediction and the integration of the information into optimising overall performance is considered in some detail, taking into account the change of charge trajectories, energy transfer and grinding efficiency as the liner wears and the profile changes.
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- 2006
21. Mill liner evolutions in recent times.
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Rattray B., Mill Operators' Conference Kalgoorlie, Western Australia 12-Oct-0014-Oct-00, Rattray B., and Mill Operators' Conference Kalgoorlie, Western Australia 12-Oct-0014-Oct-00
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Developments in mill lining design are discussed including reduced row spacing at Cadia Hill; reinforcing lifter fixings, such as the studded lifter, needed with increased grinding media size; lifter angles and lifter shadows; ball deflectors; and the trend toward larger and fewer liner pieces. Mill operators are now producing their own specifications., Developments in mill lining design are discussed including reduced row spacing at Cadia Hill; reinforcing lifter fixings, such as the studded lifter, needed with increased grinding media size; lifter angles and lifter shadows; ball deflectors; and the trend toward larger and fewer liner pieces. Mill operators are now producing their own specifications.
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- 2000
22. 148 ROFECOXIB AS ADJUNCTIVE THERAPY FOR HEMOPHILIC ARTHROPATHY
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Rattray, B. N., primary, Nugent, D. J., additional, and Young, G., additional
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- 2005
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23. Increased intragenic recombination and non-disjunction in the Rec-1 strain of Caenorhabditis elegans.
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Rattray, B. and Rose, A. M.
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- 1988
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24. Localization and Codensity Triples
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Lambek, J. and Rattray, B. A.
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u: A→H(I), I ε J], and let x: Q→S be the equalizer of ηS and Sη.
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- 1974
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25. Physiological responses to design adaptations in firefighting PPC during simulated firefighting tasks
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Anthony Walker, Argus, C., Driller, M., and Rattray, B.
26. Increased intragenic recombination and non-disjunction in the Rec-1 strain ofCaenorhabditis elegans
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Rattray, B., primary and Rose, A. M., additional
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- 1988
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27. Applications of Tensor Analysis, by A. J. McConnell. Dover, New York, 1957. xii + 318 pages . $1.85.
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Rattray, B. A., primary
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- 1960
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28. ROFECOXIB AS ADJUNCTIVE THERAPY FOR HEMOPHILIC ARTHROPATHY.
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Rattray, B. N., Nugent, D. J., and Young, G.
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- 2005
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29. Effect of elevated CO2 on rhizosphere carbon flow and soil microbialprocesses
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Paterson, E., Griffiths, B. S., Ritz, K., Hall, J. M., Rattray, B. S., and Ramsay, E. A. S.
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CARBON dioxide ,CLIMATE change ,PLANT roots ,SOIL microbiology - Abstract
Direct effects of increased above-ground CO
2 concentration on soil microbial processes are unlikely, due to the high pCO2 Of the soil atmosphere in most terrestrial ecosystems. However, below-ground microbial processes are likely to be affected through altered plant inputs at elevated CO2 . A major component ofplant input is derived from litter fall and root turnover. Inputs also derive from rhizodeposition (loss of C-compounds from active root systems) which may account for up to 40% of photoassimilate. This input fuels the activity of complex microbial communities around roots. These communities are centrally important not only to plant--microbe interactions and consequent effects on plant growth, but also, through their high relative activity and abundance, to microbially mediatedprocesses in soil generally. This review focuses on approaches to measure C-flow from roots, in particular, as affected by increased atmospheric CO2 concentration. The available evidence for impacts on microbial communities inhabiting this niche, which constitutesan interface for possible perturbations on terrestrial ecosystems through the influence of environmental change, will also be discussed. While methodologies for measuring effects of increased CO2 concentration on plant growth, physiology and C-partitioning are abundant and widely reported, there is relatively little information on plant-mediated effects on soil microbial communities and processes. Importantly, many studies have also neglected to recognize that any secondary effects on microbial communities may have profound effects onplant parameters measured in relation to environmental change. We critically review approaches which have been used to measure rhizodeposition under conditions of increased atmospheric CO2 concentration, and then consider evidence for changes in microbial communities and processes, and the methodologies which have been recently develope [ABSTRACT FROM AUTHOR]- Published
- 1997
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30. Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists
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Kevin G. Thompson, Richard Keegan, Tom Hennessey, Kristy Martin, Shona L. Halson, Paolo Menaspà, Samuele Maria Marcora, Ben Rattray, David T. Martin, Walter Staiano, Martin, K., Staiano, W., Menaspà, P., Hennessey, T., Marcora, S., Keegan, R., Thompson, K.G., Martin, D., Halson, S., and Rattray, B.
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Male ,lcsh:Medicine ,Pathology and Laboratory Medicine ,Material Fatigue ,Task (project management) ,Cognition ,0302 clinical medicine ,Time trial ,Materials Physics ,Heart Rate ,Medicine and Health Sciences ,Human Performance ,Public and Occupational Health ,lcsh:Science ,Fatigue ,Rating of perceived exertion ,Multidisciplinary ,Physics ,Classical Mechanics ,Sports Science ,mental fatigue, cycling exercise, cognitive control, inhibition, motivation, performance ,Physical Sciences ,Research Article ,Sports ,Adult ,medicine.medical_specialty ,Adolescent ,Cognitive Neuroscience ,Materials Science ,Cardiology ,Resistance (psychoanalysis) ,Young Adult ,03 medical and health sciences ,Signs and Symptoms ,Diagnostic Medicine ,Heart rate ,Reaction Time ,medicine ,Humans ,Exertion ,Sports and Exercise Medicine ,Exercise ,GV558 ,Damage Mechanics ,Behavior ,business.industry ,lcsh:R ,Biology and Life Sciences ,Physical Activity ,030229 sport sciences ,Mental Fatigue ,Bicycling ,Physical Fitness ,Stroop Test ,Physical therapy ,Cognitive Science ,Recreation ,Perception ,lcsh:Q ,business ,human activities ,030217 neurology & neurosurgery ,Neuroscience ,Stroop effect - Abstract
Purpose: Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists. Methods: After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control) for 30 min (mental exertion condition), or an easy cognitive task for 10 min (control condition) in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE) were recorded. Results: The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001). During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014). There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502). Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups. Conclusion: The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling performance. These psychobiological characteristics may be either genetic and/or developed through the training and lifestyle of professional road cyclists. © 2016 Martin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Published
- 2016
31. Does Cathodal Preconditioning Enhance the Effects of Subsequent Anodal Transcranial Direct Current Stimulation on Corticospinal Excitability and Grip Strength?
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Lewis A, Rattray B, and Flood A
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Abstract: Lewis, A, Rattray, B, and Flood, A. Does cathodal preconditioning enhance the effects of subsequent anodal transcranial direct current stimulation on corticospinal excitability and grip strength? J Strength Cond Res XX(X): 000-000, 2024-Inconsistent effects of transcranial direct current stimulation (tDCS) on corticospinal excitability (CSE) and exercise performance are commonly reported. Cathodal preconditioning, involving cathodal tDCS delivered before anodal tDCS over the same region, may enhance changes in CSE and exercise beyond that resulting from anodal tDCS alone. This study aimed to investigate whether the effects of anodal tDCS on CSE and isometric grip strength can be enhanced by cathodal preconditioning. Thirty-five healthy subjects aged 19-37 years completed a familiarization session followed by 4 stimulation conditions presented in a randomized cross-over design across 4 separate sessions. tDCS doses were applied at 2 mA over the primary motor cortex for 10 minutes. Corticospinal excitability was assessed using 120% of resting motor threshold and an input/output curve of motor evoked potentials of the first dorsal interosseous. Grip strength was evaluated as time to exhaustion (TTE) in a sustained isometric contraction. Relative to conventional sham stimulation, TTE was significantly increased by 15% after conventional anodal tDCS. Corticospinal excitability increased in response to tDCS, but this effect did not differ across conditions. Cathodal preconditioning before anodal stimulation did not increase CSE or grip strength beyond that seen in the other stimulation conditions. Our findings did not reveal any significant impact of stimulation type on CSE. Notably, anodal tDCS led to a significant improvement in grip strength endurance. However, cathodal preconditioning did not seem to increase the effect of subsequent anodal stimulation on CSE nor grip strength., (Copyright © 2024 National Strength and Conditioning Association.)
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- 2024
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32. Do not underestimate the cognitive benefits of exercise.
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Dupuy O, Ludyga S, Ortega FB, Hillman CH, Erickson KI, Herold F, Kamijo K, Wang CH, Morris TP, Brown B, Esteban-Cornejo I, Solis-Urra P, Bosquet L, Gerber M, Mekari S, Berryman N, Bherer L, Rattray B, Liu-Ambrose T, Voelcker-Rehage C, and Cheval B
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- Humans, Exercise psychology, Cognition
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- 2024
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33. The Impact of Cognitive, Physical, and Psychological Stressors on Subsequent Cognitive Performance.
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Martin K, Flood A, Pyne DB, Périard JD, Keegan R, and Rattray B
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- Humans, Workload, Cognition, Stress, Psychological psychology
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Objective: To quantify the impact of performing challenging cognitive, physical and psychological tasks on subsequent cognitive performance, and whether differences in performance are predicted by psychological variables., Background: Successful performance in many occupations depends on resilient cognition: the degree to which cognitive functions can withstand, or are resilient to, the effects of stress. Several studies have examined the effect of individual stressors on cognition; however, the capacity to compare different types of stress across studies is limited., Method: Fifty-eight participants completed cognitive, physical, psychological and control interventions, immediately preceded, and followed, by a battery of cognitive tasks. Self-efficacy and cognitive appraisal were reported at baseline. Perceived stress was recorded post-intervention. Subjective workload was recorded for each cognitive battery and intervention., Results: Cognitive performance was impaired by the cognitive, physical and psychological interventions, with the greatest effect following the cognitive intervention. The subjective workload reported for the post-intervention cognitive battery was higher following the cognitive and physical interventions. Neither self-efficacy, cognitive appraisal, perceived stress nor subjective workload of the intervention strongly predicted post-intervention performance., Conclusion: Given the differences among interventions and cognitive domains, it appears that challenges to resilient cognition are broad and varied, and the mechanism(s) by which impairment occurs is complex., Application: Considering the increase in subjective workload for the post-intervention cognitive battery, a combination of subjective and objective measures of cognitive performance monitoring should be considered., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2024
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34. The Effects of Transcranial Direct Current Stimulation and Exercise on Salivary S100B Protein Indicated Blood-Brain Barrier Permeability: A Pilot Study.
- Author
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Lewis A, Toufexis C, Goldsmith C, Robinson R, Howie G, Rattray B, and Flood A
- Abstract
Objective: This study aimed to assess the effect of transcranial direct current stimulation (tDCS) and exercise on blood-brain barrier (BBB) permeability in humans as assessed through the quantification of the salivary protein biomarker S100B. It was hypothesized that active tDCS would induce a significant increase in salivary S100B concentration when compared with sham stimulation and no stimulation. It also was hypothesized that the increase in salivary S100B concentration would be greater after active tDCS and exercise than after tDCS or exercise alone., Materials and Methods: A total of 13 healthy adults (five male, eight female), ranging in age from 21 to 32 years, underwent three experimental conditions (active tDCS, sham tDCS, inactive control). To assess exercise- and tDCS-induced changes in BBB permeability, S100B in saliva was measured. Saliva samples were taken before tDCS, after tDCS, and immediately after a ramped cycling time-to-exhaustion (TTE) task. Active tDCS involved the application of anodal stimulation over the primary motor cortex for 20 minutes at 2 mA., Results: S100B concentrations in the control condition did not differ significantly from the active condition (estimate = 0.10, SE = 0.36, t = 0.27, p = 0.79) or the sham condition (estimate = 0.33, SE = 0.36, t = 0.89, p = 0.38). Similarly, S100B concentrations at baseline did not differ significantly from post-intervention (estimate = -0.35, SE = 0.34, t = -1.03, p = 0.31) or post-TTE (estimate = 0.66, SE = 0.34, t = 1.93, p = 0.06)., Conclusions: This research provides novel insight into the effect of tDCS and exercise on S100B-indicated BBB permeability in humans. Although the effects of tDCS were not significant, increases in salivary S100B after a fatiguing cycling task may indicate exercise-induced changes in BBB permeability., Competing Interests: Conflict of Interest The authors reported no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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35. Physical activity and cognitive function in middle-aged adults: a cross-sectional analysis of the PATH through life study.
- Author
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Quinlan C, Rattray B, Pryor D, Northey JM, and Cherbuin N
- Abstract
Objectives: Investigate the independent associations of objectively measured or self-reported physical activity at different intensities with cognitive performance in middle-aged adults., Design: Cross-sectional., Methods: 156 middle-aged adults (age: 40.6 ± 1.5, 58.3% female) participated in the physical activity sub-study of the Personality and Total Health through life (PATH) project. Physical activity was measured objectively with the SenseWear™ armband (SWA), worn for seven consecutive days, and measured via self-report with a Physical Activity Recall survey (PAR). Cognitive performance was assessed with the Symbol Digit Modalities Test, the Digit Span Backwards, and an Immediate and Delayed Recall task. Associations between physical activity intensity and cognitive function were investigated in general linear models, controlling for age, sex, and education., Results: Neither objectively measured nor self-reported physical activity were associated with cognitive function at light-, moderate-, vigorous-, or combined moderate-to-vigorous intensity in this cohort of well educated, healthy middle-aged adults. Sensitivity analyses with additional moderators (e.g., body mass index, hypertension, alcohol intake) and the use of composite cognitive measures did not alter the results., Conclusion: In this cohort of middle-aged adults, objectively measured and self-reported physical activity do not appear to be associated with cognitive function. Longitudinal follow-ups utilising objective physical activity measures may be important in determining the impact of mid-life behaviours on the trajectory of cognitive changes into older age., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Quinlan, Rattray, Pryor, Northey and Cherbuin.)
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- 2023
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36. How to Tackle Mental Fatigue: A Systematic Review of Potential Countermeasures and Their Underlying Mechanisms.
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Proost M, Habay J, De Wachter J, De Pauw K, Rattray B, Meeusen R, Roelands B, and Van Cutsem J
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- Humans, Motivation, Caffeine, Mental Fatigue prevention & control
- Abstract
Introduction: Mental fatigue (MF) is a psychobiological state that impairs cognitive as well as physical performance in different settings. Recently, numerous studies have sought ways to counteract these negative effects of MF. An overview of the explored countermeasures for MF is, however, lacking., Objectives: The objective of this review is to provide an overview of the different MF countermeasures currently explored in literature. Countermeasures were classified by the timing of application (before, during or after the moment of MF) and type of intervention (behavioural, physiological and psychological)., Methods: The databases of PubMed (MEDLINE), Web of Science and PsycINFO were searched until March 7, 2022. Studies were eligible when MF was induced using a task with a duration of at least 30 min, when they assessed MF markers in at least two out of the three areas wherein MF markers have been defined (i.e., behavioural, subjective and/or [neuro]physiological) and used a placebo or control group for the countermeasure., Results: A total of 33 studies investigated one or more countermeasures against MF. Of these, eight studies assessed a behavioural countermeasure, 22 a physiological one, one a psychological countermeasure and two a combination of a behavioural and psychological countermeasure. The general finding was that a vast majority of the countermeasures induced a positive effect on behavioural (e.g., task or sport performance) and/or subjective MF markers (e.g., visual analogue scale for MF or alertness). No definitive conclusion could be drawn regarding the effect of the employed countermeasures on (neuro)physiological markers of MF as only 19 of the included studies investigated these measures, and within these a large heterogeneity in the evaluated (neuro)physiological markers was present., Discussion: Within the physiological countermeasures it seems that the use of odours during a MF task or caffeine before the MF task are the most promising interventions in combating MF. Promising behavioural (e.g., listening to music) and psychological (e.g., extrinsic motivation) countermeasures of MF have also been reported. The most assumed mechanism through which these countermeasures operate is the dopaminergic system. However, this mechanism remains speculative as (neuro)physiological markers of MF have been scarcely evaluated to date., Conclusion: The present systematic review reveals that a wide range of countermeasures have been found to successfully counteract MF on a subjective, (neuro)physiological and/or behavioural level. Of these, caffeine, odours, music and extrinsic motivation are the most evidenced for countering MF. To provide in-detail practical guidelines for the real-life application of MF countermeasures, more research must be performed into the underlying mechanisms and into the optimal dosage and time of application/intake., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
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- 2022
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37. Response to the letter to the editor regarding the article "A 4-week endurance training program improves tolerance to mental exertion in untrained individuals".
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Filipas L, Martin K, Northey JM, La Torre A, Keegan R, and Rattray B
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- Humans, Muscle, Skeletal, Physical Endurance, Physical Exertion, Endurance Training
- Published
- 2021
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38. Development and Initial Validation of an Acute Readiness Monitoring Scale in Military Personnel.
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Keegan RJ, Flood A, Niyonsenga T, Welvaert M, Rattray B, Sarkar M, Melberzs L, and Crone D
- Abstract
Personnel in many professions must remain "ready" to perform diverse activities. Managing individual and collective capability is a common concern for leadership and decision makers. Typical existing approaches for monitoring readiness involve keeping detailed records of training, health and equipment maintenance, or - less commonly - data from wearable devices that can be difficult to interpret as well as raising privacy concerns. A widely applicable, simple psychometric measure of perceived readiness would be invaluable in generating rapid evaluations of current capability directly from personnel. To develop this measure, we conducted exploratory factor analysis and confirmatory factor analysis with a sample of 770 Australian military personnel. The 32-item Acute Readiness Monitoring Scale (ARMS) demonstrated good model fit, and comprised nine factors: overall readiness; physical readiness; physical fatigue; cognitive readiness; cognitive fatigue; threat-challenge (i.e., emotional/coping) readiness; skills-and-training readiness; group-team readiness, and equipment readiness. Readiness factors were negatively correlated with recent stress, current negative affect and distress, and positively correlated with resilience, wellbeing, current positive affect and a supervisor's rating of solider readiness. The development of the ARMS facilitates a range of new research opportunities: enabling quick, simple and easily interpreted assessment of individual and group readiness., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Keegan, Flood, Niyonsenga, Welvaert, Rattray, Sarkar, Melberzs and Crone.)
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- 2021
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39. The Acute Readiness Monitoring Scale: Assessing Predictive and Concurrent Validation.
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Summers SJ, Keegan RJ, Flood A, Martin K, McKune A, and Rattray B
- Abstract
To complement and enhance readiness-monitoring capability, the Acute Readiness Monitoring Scale (ARMS) was developed: a widely applicable, simple psychometric measure of perceived readiness. While this tool may have widespread utility in sport and military settings, it remains unknown if the ARMS demonstrates predictive and concurrent validity. Here, we investigated whether the ARMS is: (1) responsive to an acute manipulation of readiness using sleep deprivation, (2) relates to biological markers of readiness [cortisol/heart-rate variability (HRV)], and (3) predicts performance on a cognitive task. Thirty young adults (aged 23 ± 4 years; 18 females) participated. All participants engaged in a 24-h sleep deprivation protocol. Participants completed the ARMS, biological measures of readiness (salivary cortisol, HRV), and cognitive performance measures (psychomotor vigilance task) before, immediately after, 24-, and 48-h post-sleep deprivation. All six of the ARMS subscales changed in response to sleep deprivation: scores on each subscale worsened (indicating reductions in perceived readiness) immediately after sleep deprivation, returning to baseline 24/48 h post. Lower perceived readiness was associated with reduced awakening responses in cortisol and predicted worse cognitive performance (slower reaction time). No relationship was observed between the ARMS and HRV, nor between any biological markers of readiness (cortisol/HRV) and cognitive performance. These data suggest that the ARMS may hold practical utility in detecting, or screening for, the wide range of deleterious effects caused by sleep deprivation; may constitute a quick, cheap, and easily interpreted alternative to biological measures of readiness; and may be used to monitor or mitigate potential underperformance on tasks requiring attention and vigilance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Summers, Keegan, Flood, Martin, McKune and Rattray.)
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- 2021
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40. The accuracy of self-reported physical activity questionnaires varies with sex and body mass index.
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Quinlan C, Rattray B, Pryor D, Northey JM, Anstey KJ, Butterworth P, and Cherbuin N
- Subjects
- Adult, Energy Metabolism, Female, Humans, Male, Surveys and Questionnaires, Young Adult, Body Mass Index, Exercise, Mental Recall physiology, Metabolic Equivalent, Monitoring, Physiologic statistics & numerical data, Motor Activity physiology, Self Report
- Abstract
Background: Factors contributing to the accurate measurement of self-reported physical activity are not well understood in middle-aged adults. We investigated the associations between two self-reported surveys and objectively measured physical activity in middle-aged adults, and the influence of individual and sociodemographic factors on these associations, at different intensities utilizing an observational study design., Methods: Participants (n = 156) wore a SenseWear Armband™ (SWA) for a continuous seven-day period over the triceps of the left arm, to measure energy expenditure in metabolic equivalents. Participants also completed the Physical Activity Recall questionnaire (PAR) and Active Australia Survey (AAS). Associations were analyzed separately in general linear models for each intensity. The influence of individual and sociodemographic factors was assessed through moderator analyses., Results: The PAR and SWA were significantly positively associated at moderate (β = 0.68, 95% CI 0.16-1.20), vigorous (β = 0.36, 95% CI 0.20-0.53), moderate-to-vigorous physical activity (MVPA) (β = 0.52, 95% CI 0.20-0.83), and total METmins (β = 0.63, 95% CI 0.35-0.90), the AAS and SWA were associated at all intensities (moderate (β = 0.41, 95% CI 0.15-0.67), vigorous (β = 0.32, 95% CI 0.19-0.46), MVPA (β = 0.42, 95% CI 0.18-0.65) and total METmins (β = 0.62, 95% CI 0.29-0.96). A significant interaction between the PAR and sex for vigorous-intensity unveiled a weaker association in women. Both surveys tended to under-report physical activity. The largest margins of error were present at light and moderate intensities. For the PAR, participants reported over 20 hours, or 69% less light physical activity than recorded by the SWA per week. For the AAS, participants reported over 7 hours, or 38% less moderate physical activity. Compared to lighter intensities, time spent at a vigorous intensity was overreported by participants with the PAR and AAS by 91 and 43 minutes per week, respectively. The addition of Body Mass Index (BMI) resulted in non-significant interactions between the PAR and SWA for moderate-intensity, and the AAS and SWA for vigorous-intensity; a significant interaction between AAS and BMI indicated that the strength of the association differed by BMI for vigorous-intensity., Conclusions: The PAR and AAS are not equivalent to the SWA, and sex and BMI may alter the associations between the measures., Competing Interests: The authors have declared that no competing itnerests exist
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- 2021
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41. A Short-Term Intervention of High-Intensity Exercise and Anodal-tDCS on Motor Learning in Middle-Aged Adults: An RCT.
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Quinlan C, Rattray B, Pryor D, Northey JM, Coxon J, Cherbuin N, and Andrews SC
- Abstract
High-intensity exercise has enhanced motor learning in healthy young adults. Anodal-transcranial direct current stimulation (a-tDCS) may optimize these effects. This study aimed to determine the effects of a short-term high-intensity interval exercise intervention either with or without a-tDCS on the learning and retention of a novel motor task in middle-aged adults. Forty-two healthy middle-aged adults (age = 44.6 ± 6.3, female = 76%) were randomized into three groups: exercise and active a-tDCS, exercise and sham a-tDCS, and a non-exercise and sham a-tDCS control. Participants completed a baseline testing session, followed by three intervention sessions 48-h apart. The exercise groups completed 20-min of high-intensity exercise followed by a novel sequential visual isometric pinch task (SVIPT) while receiving 20-min of 1.5 mA a-tDCS, or sham tDCS. The control group completed 20-min of reading before receiving sham a-tDCS during the SVIPT. Learning was assessed by skill change within and between intervention sessions. Participants returned 5-7 days after the final intervention session and performed the SVIPT task to assess retention. All three groups showed evidence of learning on the SVIPT task. Neither group displayed enhanced overall learning or retention when compared to the control group. High-intensity exercise with or without a-tDCS did not improve learning or retention of a novel motor task in middle-aged adults. The methodological framework provides direction for future research to investigate the potential of differing exercise intensity effects on learning and retention., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Quinlan, Rattray, Pryor, Northey, Coxon, Cherbuin and Andrews.)
- Published
- 2021
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42. Quinine Ingestion During the Latter Stages of a 3,000-m Time Trial Fails to Improve Cycling Performance.
- Author
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Etxebarria N, Clark B, Ross ML, Hui T, Goecke R, Rattray B, and Burke LM
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- Administration, Oral, Cross-Over Studies, Double-Blind Method, Humans, Male, Perception physiology, Physical Exertion physiology, Solutions, Bicycling physiology, Performance-Enhancing Substances administration & dosage, Physical Endurance drug effects, Quinine administration & dosage
- Abstract
The ingestion of quinine, a bitter tastant, improves short-term (30 s) cycling performance, but it is unclear whether this effect can be integrated into the last effort of a longer race. The purpose of this study was to determine whether midtrial quinine ingestion improves 3,000-m cycling time-trial (TT) performance. Following three familiarization TTs, 12 well-trained male cyclists (mean ± SD: mass = 76.6 ± 9.2 kg, maximal aerobic power = 390 ± 50 W, maximal oxygen uptake = 4.7 ± 0.6 L/min) performed four experimental 3,000-m TTs on consecutive days. This double-blind, crossover design study had four randomized and counterbalanced conditions: (a) Quinine 1 (25-ml solution, 2 mM of quinine); (b) Quinine 2, replicate of Quinine 1; (c) a 25-ml sweet-tasting no-carbohydrate solution (Placebo); and (d) 25 ml of water (Control) consumed at the 1,850-m point of the TT. The participants completed a series of perceptual scales at the start and completion of all TTs, and the power output was monitored continuously throughout all trials. The power output for the last 1,000 m for all four conditions was similar: mean ± SD: Quinine 1 = 360 ± 63 W, Quinine 2 = 367 ± 63 W, Placebo = 364 ± 64 W, and Control = 367 ± 58 W. There were also no differences in the 3,000-m TT power output between conditions. The small perceptual differences between trials at specific 150-m splits were not explained by quinine intake. Ingesting 2 mM of quinine during the last stage of a 3,000-m TT did not improve cycling performance.
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- 2021
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43. A 4-week endurance training program improves tolerance to mental exertion in untrained individuals.
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Filipas L, Martin K, Northey JM, La Torre A, Keegan R, and Rattray B
- Subjects
- Adaptation, Physiological, Adult, Brain physiology, Cognition physiology, Female, Humans, Male, Perception, Time Factors, Young Adult, Endurance Training methods, Endurance Training psychology, Mental Fatigue prevention & control, Physical Exertion
- Abstract
Objectives: The aim of this study was to investigate whether 4 weeks of endurance training could improve tolerance to mental exertion in untrained participants., Design: Longitudinal training study., Methods: Twenty untrained young adults (14 F, 6 M; 27.6±6.2 years) completed a 4-week training protocol in a randomised and counterbalanced order. Baseline and follow-up assessment were conducted over three sessions in the week preceding and following the training period. During session 1, participants completed an incremental maximal ramp test. During sessions 2 and 3 participants completed a 15min cycling time trial preceded by either a mental exertion or control conditions. Following baseline assessments, participants were randomised into a physical training or placebo group that completed the training intervention thrice weekly over four weeks., Results: The physical training resulted in increase in VO
2 peak relative to the placebo group (p=0.003). Linear Mixed Models utilising the control condition time trial performance as a covariate found the physical training group increased their time trial distance following the mental exertion condition to a greater extent than the placebo group (p=0.03). RPE during the time trial and perceptual measures of mental exertion did not significantly change between groups (all p>0.10) although interaction effects were observed when considering the RPE-power output relationship during the time trial., Conclusions: Four weeks of endurance training increased tolerance to mental exertion in untrained participants during a subsequent physical performance, but not during prolonged cognitive performance. This finding suggests that the ability to tolerate mental exertion is trainable in at least some contexts and highlights the far-reaching benefits of endurance training., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)- Published
- 2020
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44. Objectively measured physical activity is associated with dorsolateral prefrontal cortex volume in older adults.
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Northey JM, Rattray B, Pumpa KL, Pryor DJ, Fraser MA, Shaw ME, Anstey KJ, and Cherbuin N
- Subjects
- Actigraphy, Aged, Cohort Studies, Female, Humans, Magnetic Resonance Imaging, Male, Wearable Electronic Devices, Aging physiology, Executive Function physiology, Exercise physiology, Gray Matter anatomy & histology, Hippocampus anatomy & histology, Prefrontal Cortex anatomy & histology, Psychomotor Performance physiology
- Abstract
Background: Epidemiological studies suggest physical activity (PA) can slow or prevent both cognitive decline and age-related atrophy in frontal and hippocampal gray matter volumes. However, much of this evidence is based on self-reported measures of PA., Methods: PA was measured objectively with a SenseWear™ Armband to examine the cross-sectional associations between the duration of light, moderate and vigorous intensity PA with gray matter volume in the dorsolateral prefrontal cortex (DLPFC) and hippocampus in 167 (female: 43%) cognitively healthy older adults aged 73 to 78., Results: The duration of objective moderate to vigorous intensity physical activity (MVPA) was associated with a greater volume of the right DLPFC (β = 0.16; p = 0.04). In addition, objective moderate-intensity PA alone was also associated with greater volume of the left (β = 0.17; p = 0.03) and right (β = 0.19; p = 0.01) DLPFC after controlling for covariates and adjustment for multiple comparisons. In contrast, there were no significant associations between light- or vigorous-intensity PA and gray matter volumes (all p > 0.05). No associations between PA and cognitive performance were detected, and self-reported PA was not associated with any of the outcomes investigated., Conclusions: These findings suggest that an intensity-dependent relationship may exist, whereby a greater duration of MVPA, perhaps driven by moderate-intensity PA, is associated with preserved gray matter volume in frontal regions of the brain. Future research should investigate the mechanisms of this dose-effect and determine whether greater brain volumes associated with objective PA convey protective effects against cognitive decline., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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45. The impact of different training load quantification and modelling methodologies on performance predictions in elite swimmers.
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Mitchell LJG, Rattray B, Fowlie J, Saunders PU, and Pyne DB
- Subjects
- Female, Humans, Male, Muscle Strength, Young Adult, Athletic Performance physiology, Models, Theoretical, Neural Networks, Computer, Physical Exertion physiology, Swimming physiology
- Abstract
The use of rolling averages to analyse training data has been debated recently. We evaluated two training load quantification methods (five-zone, seven-zone) fitted to performances over two race distances (50 and 100 m) using four separate longitudinal models (Banister, Busso. rolling averages and exponentially weighted rolling averages) for three swimmers ranked in the top 8 in the world. A total of 1610 daily load measures and 108 performances were collected. Banister (standard error of the estimate (SEE) 0.64 and 0.62 s; five-zone and seven-zone quantification methods), Busso (SEE 0.73 and 0.70 s) and exponentially weighted rolling averages (SEE 0.57 and 0.63 s) models fitted more accurately ( p < 0.001) than the rolling averages approach (SEE 1.32 and 1.36 s). The seven-zone quantification method did not produce more accurate performance predictions than the five-zone method, despite being a more detailed form of training load quantification. Four neural network models were fitted and had a lower error (SEE 0.38, 0.41, 0.35 and 0.60 s) than all longitudinal models, but did not track as predictably over time. Exponentially weighted impulse-response models and exponentially weighted rolling averages appear more effective at predicting performance using training load data in elite swimmers than a rolling averages approach.
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- 2020
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46. Towards an understanding of the physical activity-BDNF-cognition triumvirate: A review of associations and dosage.
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Walsh EI, Smith L, Northey J, Rattray B, and Cherbuin N
- Subjects
- Aging, Humans, Brain-Derived Neurotrophic Factor, Cognition, Exercise, Healthy Aging
- Abstract
Physical activity has received substantial research attention due to its beneficial impact on cognition in ageing, particularly via the action of brain-derived neurotrophic factor (BDNF). It is well established that physical activity can elevate circulating levels of BDNF, and that BDNF has neurotrophic, neuroprotective and cognitively beneficial properties. Yet, practical implementation of this knowledge is limited by a lack of clarity on context and dose-effect. Against a shifting backdrop of gradually diminishing physical and cognitive capacity in normal ageing, the type, intensity, and duration of physical activity required to elicit elevations in BDNF, and more importantly, the magnitude of BDNF elevation required for detectable neuroprotection remains poorly characterised. The purpose of this review is to provide an overview of the association between physical activity, BDNF, and cognition, with a focus on clarifying the magnitude of these effects in the context of normative ageing. We discuss the implications of the available evidence for the design of physical activity interventions intended to promote healthy cognitive ageing., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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47. Physiological Factors Which Influence Cognitive Performance in Military Personnel.
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Martin K, Périard J, Rattray B, and Pyne DB
- Subjects
- Humans, Cardiorespiratory Fitness physiology, Cognition physiology, Decision Making physiology, Fatigue physiopathology, Military Personnel, Nutritional Status physiology, Psychomotor Performance physiology, Visual Acuity physiology
- Abstract
Objective: To identify and detail physiological factors that influence cognition in military personnel., Background: Maintenance of cognitive and task performance is important under several scenarios, none more so than in a military context. Personnel are prepared for and trained to tolerate many of the stressors they encounter; however, consideration of stressors typically extends only as far as the physical, psychological, and environmental requirements of a given task. While considering these factors certainly characterizes the broader picture, several physiological states and traits can influence cognition and thus, should also be considered., Method: A systematic review of the electronic databases Medline (PubMed), EMBASE (Scopus), PsycINFO, and Web of Science was conducted from inception up to January 2019. Eligibility criteria included current military personnel, an outcome of cognition, and the assessment of a physiological factor., Results: The search returned 60,564 records, of which 60 were included in the review. Eleven studies examined the impact of demographic factors on cognition, 16 examined fatigue, 10 investigated nutrition, and 24 the impact of biological factors on cognitive performance., Conclusion: Factors identified as having a positive impact on cognition include aerobic fitness, nutritional supplementation, and visual acuity. In contrast, factors identified as having a negative impact include fatigue arising from sustained operations, dehydration, undernutrition, and an exaggerated physiological stress response to a cognitive task or a stressor. A further subset of these factors was considered modifiable., Application: The modifiable factors identified provide avenues for training and preparation to enhance cognition in ways previously unconsidered.
- Published
- 2020
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48. The Impact of Environmental Stress on Cognitive Performance: A Systematic Review.
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Martin K, McLeod E, Périard J, Rattray B, Keegan R, and Pyne DB
- Subjects
- Humans, Cognition physiology, Environment, Military Personnel, Psychomotor Performance physiology, Stress, Physiological physiology
- Abstract
Objective: In this review, we detail the impact of environmental stress on cognitive and military task performance and highlight any individual characteristics or interventions which may mitigate any negative effect., Background: Military personnel are often deployed in regions markedly different from their own, experiencing hot days, cold nights, and trips both above and below sea level. In spite of these stressors, high-level cognitive and operational performance must be maintained., Method: A systematic review of the electronic databases Medline (PubMed), EMBASE (Scopus), PsycINFO, and Web of Science was conducted from inception up to September 2018. Eligibility criteria included a healthy human cohort, an outcome of cognition or military task performance and assessment of an environmental condition., Results: The search returned 113,850 records, of which 124 were included in the systematic review. Thirty-one studies examined the impact of heat stress on cognition; 20 of cold stress; 59 of altitude exposure; and 18 of being below sea level., Conclusion: The severity and duration of exposure to the environmental stressor affects the degree to which cognitive performance can be impaired, as does the complexity of the cognitive task and the skill or familiarity of the individual performing the task., Application: Strategies to improve cognitive performance in extreme environmental conditions should focus on reducing the magnitude of the physiological and perceptual disturbance caused by the stressor. Strategies may include acclimatization and habituation, being well skilled on the task, and reducing sensations of thermal stress with approaches such as head and neck cooling.
- Published
- 2019
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49. Are Individuals Who Engage in More Frequent Self-Regulation Less Susceptible to Mental Fatigue?
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Martin K, Thompson KG, Keegan R, and Rattray B
- Abstract
The aim of this study was to investigate whether individuals who engage in more frequent self-regulation are less susceptible to mental fatigue. Occupational cognitive demand and participation in sports or exercise were quantified as activities requiring self-regulation. Cardiorespiratory fitness was also assessed. On separate occasions, participants either completed 90 min of an incongruent Stroop task (mental exertion condition) or watched a 90-min documentary (control condition). Participants then completed a cycling time-to-exhaustion (physical endurance) test. There was no difference in the mean time to exhaustion between conditions, although individual responses varied. Occupational cognitive demand, participation in sports or exercise, and cardiorespiratory fitness predicted the change in endurance performance (p = .026, adjusted R2 = .279). Only cognitive demand added significantly to the prediction (p = .024). Participants who reported higher levels of occupational cognitive demand better maintained endurance performance following mental exertion.
- Published
- 2019
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50. Responsiveness and Seasonal Variation of a 12x25m Swimming Test.
- Author
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Mitchell LJG, Rattray B, Wu P, Saunders PU, and Pyne DB
- Subjects
- Adolescent, Bayes Theorem, Cross-Sectional Studies, Female, Humans, Longitudinal Studies, Male, Young Adult, Athletic Performance trends, Swimming physiology, Time Factors
- Abstract
Purpose: Critical speed (CS) and supra-CS distance capacity (D') are useful metrics for monitoring changes in swimmers' physiological and performance capacities. However, the utility of these metrics across a season has not been systematically evaluated in high level swimmers., Methods: Twenty-seven swimmers (18 female; age 19.1 ± 2.9 y, 9 male; 19.5 ± 1.9 y, mean ± SD) completed the 12x25m swimming test multiple times (4 ± 3 tests/swimmer) across a two-year period. Season-best times in all distances for the test stroke were sourced from publicly available databases. Swimmers' distance speciality was determined as the event with the time closest to world record. Four metrics were calculated from the 12x25m test: CS, D', peak speed and drop off %., Results: Guyatt's Responsiveness Index values were calculated to ascertain the practically relevant sensitivity of each 12x25m metric: CS = 1.5, peak speed = 2.3, D' = 2.1 and drop off % = 2.6. These values are modified effect sizes (ES); all are large effects. Bayesian mixed-modelling showed substantial between-subject differences between genders and strokes for each variable, but minimal within-subject changes across the season. Drop off % was lower in 200 m swimmers (14.0 ± 3.3%) compared to 100 m swimmers (18.1 ± 4.1%, p = 0.003, ES = 1.10)., Conclusion: The 12x25m test is best suited to differentiating between swimmers of different strokes and events. Further development is needed to improve its utility in quantifying meaningful changes over a season for individual swimmers.
- Published
- 2019
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