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Burma JS, Macaulay A, Copeland P, Khatra O, Bouliane KJ, Smirl JD. Comparison of cerebrovascular reactivity recovery following high-intensity interval training and moderate-intensity continuous training. Physiol Rep 2021; 8:e14467. [PMID: 32506845 PMCID: PMC7276190 DOI: 10.14814/phy2.14467] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 04/21/2020] [Accepted: 04/25/2020] [Indexed: 12/27/2022] Open
Abstract
A common inclusion criterion when assessing cerebrovascular (CVR) metrics is for individuals to abstain from exercise for 12–24 hr prior to data collections. While several studies have examined CVR during exercise, the literature describing CVR throughout post‐exercise recovery is sparse. The current investigation examined CVR measurements in nine participants (seven male) before and for 8 hr following three conditions: 45‐min moderate‐continuous exercise (at ~50% heart‐rate reserve), 25‐min high‐intensity intervals (ten, one‐minute intervals at ~85% heart‐rate reserve), and a control day (30‐min quiet rest). The hypercapnic (40–60 mmHg) and hypocapnic (25–40 mmHg) slopes were assessed via a modified rebreathing technique and controlled stepwise hyperventilation, respectively. All testing was initiated at 8:00a.m. with transcranial Doppler ultrasound measurements to index cerebral blood velocity performed prior to the condition (pre) with serial follow‐ups at zero, one, two, four, six, and eight hours within the middle and posterior cerebral artery (MCA, PCA). Absolute and relative MCA and PCA hypercapnic slopes were attenuated following high‐intensity intervals at hours zero and one (all p < .02). No alterations were observed in either hypocapnic or hypercapnic slopes following the control or moderate‐continuous exercise (all p > .13), aside from a reduced relative hypercapnic MCA slope at hours zero and one following moderate‐continuous exercise (all p < .005). The current findings indicate the common inclusion criteria of a 12–24 hr time restriction on exercise can be reduced to two hours when performing CVR measures. Furthermore, the consistent nature of the CVR indices throughout the control day indicate reproducible testing sessions can be made between 8:00a.m. and 7:00p.m.
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Affiliation(s)
- Joel S Burma
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, University of Calgary, Calgary, AB, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Alannah Macaulay
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Paige Copeland
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Kevin J Bouliane
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada
| | - Jonathan D Smirl
- Sport Concussion Research Lab, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, University of Calgary, Calgary, AB, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute, University of Calgary, Calgary, AB, Canada
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Burma JS, Copeland P, Macaulay A, Khatra O, Wright AD, Smirl JD. Dynamic cerebral autoregulation across the cardiac cycle during 8 hr of recovery from acute exercise. Physiol Rep 2021; 8:e14367. [PMID: 32163235 PMCID: PMC7066871 DOI: 10.14814/phy2.14367] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 12/28/2019] [Accepted: 12/30/2019] [Indexed: 01/02/2023] Open
Abstract
Current protocols examining cerebral autoregulation (CA) parameters require participants to refrain from exercise for 12–24 hr, however there is sparse objective evidence examining the recovery trajectory of these measures following exercise across the cardiac cycle (diastole, mean, and systole). Therefore, this study sought to determine the duration acute exercise impacts CA and the within‐day reproducibility of these measures. Nine participants performed squat–stand maneuvers at 0.05 and 0.10 Hz at baseline before three interventions: 45‐min moderate‐continuous exercise (at 50% heart‐rate reserve), 30‐min high‐intensity intervals (ten, 1‐min at 85% heart‐rate reserve), and a control day (30‐min quiet rest). Squat–stands were repeated at hours zero, one, two, four, six, and eight after each condition. Transcranial doppler ultrasound of the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was used to characterize CA parameters across the cardiac cycle. At baseline, the systolic CA parameters were different than mean and diastolic components (ps < 0.015), however following both exercise protocols in both frequencies this disappeared until hour four within the MCA (ps > 0.079). In the PCA, phase values were affected only following high‐intensity intervals until hour four (ps > 0.055). Normalized gain in all cardiac cycle domains remained different following both exercise protocols (ps < 0.005) and across the control day (p < .050). All systolic differences returned by hour six across all measures (ps < 0.034). Future CA studies may use squat–stand maneuvers to assess the cerebral pressure–flow relationship 6 hr after exercise. Finally, CA measures under this paradigm appear to have negligible within‐day variation, allowing for reproducible interpretations to be drawn.
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Affiliation(s)
- Joel S Burma
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Center, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Paige Copeland
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Alannah Macaulay
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Alexander D Wright
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,MD/PhD Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.,Southern Medical Program, University of British Columbia, Kelowna, BC, Canada
| | - Jonathan D Smirl
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada.,Sport Injury Prevention Research Center, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.,Southern Medical Program, University of British Columbia, Kelowna, BC, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
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Khatra O, Shadgan A, Taunton J, Pakravan A, Shadgan B. A Bibliometric Analysis of the Top Cited Articles in Sports and Exercise Medicine. Orthop J Sports Med 2021; 9:2325967120969902. [PMID: 33553441 PMCID: PMC7841868 DOI: 10.1177/2325967120969902] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 06/17/2020] [Indexed: 12/26/2022] Open
Abstract
Background: Although citation analysis is common in many areas of medicine, there is a lack of similar research in sports and exercise medicine. Purpose: To identify and examine the characteristics of the 100 top cited articles in the field of sports and exercise medicine in an effort to determine what components make an article highly influential. Study Design: Cross-sectional study. Methods: The Web of Science, Scopus, and PubMed databases were used to determine the 100 top cited articles from 46 journals in the field of sports and exercise medicine. Each of the 100 articles was then analyzed by 2 independent reviewers, and results were compared. Basic information was collected, including journal title, country of origin, and study type. Different categories were compared using descriptive statistics of counts or percentages. Results: The 100 top cited articles were published in 15 of the 46 identified sports and exercise medicine journals, with the most prolific being Medicine and Science in Sports and Exercise (n = 49), American Journal of Sports Medicine (n = 18), and Sports Medicine (n = 7). In terms of country of origin, the top 3 contributors were the United States (n = 65), Canada (n = 9), and Sweden (n = 8). The most commonly researched anatomic areas were the knee (n = 15) and the brain (n = 3). Narrative reviews were the most common study type (n = 38), and only a single study on the 100 top cited articles list used a randomized controlled trial design. The most prevalent fields of study were exercise science (55% of articles) and well-being (16% of articles). Conclusion: Narrative reviews from the United States and published in English-language journals were the most likely to be highly cited. In addition, the knee was a common anatomic area of study on the top cited list of research in sports and exercise medicine
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Affiliation(s)
- Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Armita Shadgan
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, Canada
| | - Jack Taunton
- Division of Sports Medicine, Allan McGavin Sports Medicine Centre, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Amir Pakravan
- European College of Sport and Exercise Physicians, London, UK
| | - Babak Shadgan
- Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, Vancouver, Canada
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Burma JS, Macaulay A, Copeland PV, Khatra O, Bouliane KJ, Smirl JD. Temporal evolution of neurovascular coupling recovery following moderate- and high-intensity exercise. Physiol Rep 2021; 9:e14695. [PMID: 33463899 PMCID: PMC7814491 DOI: 10.14814/phy2.14695] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Studies examining neurovascular coupling (NVC) require participants to refrain from exercise for 12-24 hours. However, there is a paucity of empirical evidence for this restriction. The objectives for this study were to delineate the time-course recovery of NVC metrics following exercise and establish the NVC within- and between-day reliability. METHODS Nine participants completed a complex visual search paradigm to assess NVC via transcranial Doppler ultrasound of the posterior cerebral artery blood velocity (PCA). Measurements were performed prior to and throughout the 8-hour recovery period following three randomized conditions: 45 minutes of moderate-intensity exercise (at 50% heart-rate reserve), 30 minutes high-intensity intervals (10, 1-minute intervals at 85% heart-rate reserve), and control (30 minutes quiet rest). In each condition, baseline measures were collected at 8:00am with serial follow-ups at hours zero, one, two, four, six, and eight. RESULTS Area-under-the-curve and time-to-peak PCA velocity during the visual search were attenuated at hour zero following high-intensity intervals (all p < 0.05); however, these NVC metrics recovered at hour one (all p > 0.13). Conversely, baseline PCA velocity, peak PCA velocity, and the relative percent increase were not different following high-intensity intervals compared to baseline (all p > 0.26). No NVC metrics differed from baseline following both moderate exercise and control conditions (all p > 0.24). The majority of the NVC parameters demonstrated high levels of reliability (intraclass correlation coefficient: >0.90). CONCLUSION Future NVC assessments can take place a minimum of one hour following exercise. Moreover, all metrics did not change across the control condition, therefore future studies using this methodology can reliably quantify NVC between 8:00am and 7:00 pm.
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Affiliation(s)
- Joel S. Burma
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryABCanada
| | - Alannah Macaulay
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- School of Health Sciences, Nuclear MedicineBritish Columbia Institute of TechnologyBurnabyBCCanada
| | - Paige V. Copeland
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Omeet Khatra
- Faculty of MedicineUniversity of British ColumbiaVancouverBCCanada
| | - Kevin J. Bouliane
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Jonathan D. Smirl
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryABCanada
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Burma JS, Copeland PV, Macaulay A, Khatra O, Smirl JD. Effects of high-intensity intervals and moderate-intensity exercise on baroreceptor sensitivity and heart rate variability during recovery. Appl Physiol Nutr Metab 2020; 45:1156-1164. [DOI: 10.1139/apnm-2019-0810] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Numerous studies have examined heart rate variability (HRV) and cardiac baroreceptor sensitivity (BRS) variables during recovery both acutely (under 3 h) and long-term (24, 48, and 72 h) postexercise. However, there is little literature examining HRV and BRS measures between these timepoints. Spontaneous short-term HRV and cardiac BRS measures were collected in 9 participants before and at zero, 1, 2, 4, 6, and 8 h after 3 separate conditions: moderate-intensity continuous exercise (MICE; 45 min at 50% heart rate reserve), high-intensity interval exercise (HIIE; 25 min including ten 1-min intervals at 85% heart rate reserve), and control (30 min quiet rest). HRV measures in the time domain were only affected immediately following HIIE and MICE at hour zero (all p < 0.043), whereas frequency-domain metrics were unaltered (all p > 0.102). These measures were highly consistent across the control day (all p > 0.420). Cardiac BRS was assessed via low-frequency (LF) gain, and revealed reductions following HIIE at hour zero (p < 0.012). Cardiac BRS LF gain remained consistent following MICE and control interventions (all p > 0.280). The common practice of waiting 12 to 24 h is overly conservative as the current findings demonstrate measures return to baseline at ∼60 min after exercise. Moreover, these metrics demonstrated high levels of within- and between-day reliability. Novelty Previously a 12-h minimum restriction from exercise was required before participation in HRV/BRS studies. Recovery from moderate-intensity exercise for HRV and BRS metrics was <60 min; whereas, high-intensity intervals led to alterations for approximately 60 min. Spontaneous HRV and cardiac BRS demonstrated high levels of within-day reproducibility.
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Affiliation(s)
- Joel S. Burma
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC V1V 1V7, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Paige V. Copeland
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC V1V 1V7, Canada
| | - Alannah Macaulay
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC V1V 1V7, Canada
- School of Health Sciences, Nuclear Medicine, British Columbia Institute of Technology, Burnaby, BC V6T 1Z4, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jonathan D. Smirl
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC V1V 1V7, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 1N4, Canada
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB T2N 1N4, Canada
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Burma JS, Copeland P, Macaulay A, Khatra O, Smirl JD. Comparison of diurnal variation, anatomical location, and biological sex within spontaneous and driven dynamic cerebral autoregulation measures. Physiol Rep 2020; 8:e14458. [PMID: 32537905 PMCID: PMC7293969 DOI: 10.14814/phy2.14458] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/04/2020] [Accepted: 04/10/2020] [Indexed: 01/31/2023] Open
Abstract
Presently, the literature describing the influence of diurnal variation on dynamic cerebral autoregulation (dCA) metrics is sparse. Additionally, there is little data with respect to dCA comparisons between anterior/posterior circulation beds and biological sexes using squat-stand maneuvers. Eight male and eight female participants (n = 16) performed 5 min of spontaneous upright rest and squat-stand maneuvers at 0.05 and 0.10 Hz across seven time points throughout the day. All testing sessions commenced at 8:00 a.m. each day and dCA parameters were quantified across the cardiac cycle (diastole, mean, and systole) using transcranial Doppler ultrasound to insonate cerebral blood velocity within the middle and posterior cerebral arteries (MCA, PCA). No cardiac cycle alternations were seen spontaneous (all p > .207) while a trend was noted in some driven (all p > .051) dCA metrics. Driven dCA produced much lower coefficient of variances (all <21%) compared with spontaneous (all <58%). Moreover, no sex differences were found within driven metrics (all p > .096). Between vessels, PCA absolute gain was reduced within all spontaneous and driven measures (all p < .014) whereas coherence, phase, and normalized gain were unchanged (all p > .099). There appears to be little influence of diurnal variation on dCA measures across the day (8:00 a.m. to 6:00 p.m.). Absolute gain was blunted in the PCA relative to the MCA and consistent with previous literature, driven methods demonstrated vastly improved reproducibility metrics compared to spontaneous methods. Finally, no dCA differences were found between biological sexes, demonstrating that males and females regulate in a harmonious manner, when females are tested within the early follicular phase of the menstrual cycle.
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Affiliation(s)
- Joel S. Burma
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
| | - Paige Copeland
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Alannah Macaulay
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
| | - Omeet Khatra
- Faculty of MedicineUniversity of British ColumbiaVancouverBCCanada
| | - Jonathan D. Smirl
- Concussion Research LaboratoryFaculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBCCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryABCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryCalgaryABCanada
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Smirl JD, Jones KE, Copeland P, Khatra O, Taylor EH, Van Donkelaar P. Characterizing symptoms of traumatic brain injury in survivors of intimate partner violence. Brain Inj 2019; 33:1529-1538. [DOI: 10.1080/02699052.2019.1658129] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Jonathan D. Smirl
- School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - K. Elisabeth Jones
- School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Paige Copeland
- School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Omeet Khatra
- Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Edward H. Taylor
- School of Social Work, University of British Columbia, Kelowna, British Columbia, Canada
| | - Paul Van Donkelaar
- School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
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