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Wegener F, Ritterbusch A, Saal C, Baumgart C, Hoppe MW. Myotonometry and extended field-of-view ultrasound imaging allow reliable quantification of patellar tendon stiffness and length at rest and during maximal load, whereas several restrictions exist for the Achilles tendon. Front Sports Act Living 2024; 6:1379506. [PMID: 38859890 PMCID: PMC11163091 DOI: 10.3389/fspor.2024.1379506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 05/07/2024] [Indexed: 06/12/2024] Open
Abstract
Introduction Stiffness and length are well-established tendon parameters in sports and medicine. Myotonometry and ultrasound imaging are the commonly used methods to quantify these parameters. However, further studies are needed to clarify the reliability of these methods, especially when assessing maximally loaded tendons and when conducted by different experienced investigators. This study aimed to determine the intra- and interrater reliabilities of measuring the stiffness and length of the patellar tendon (PT) and Achilles tendon (AT) using the myotonometry method and the extended field-of-view ultrasound (EFOV-US) technique at rest and maximal load performed by different experienced investigators. Methods Twenty-seven participants were examined on three different days by one experienced investigator and one novice investigator. Primary outcomes were the intraclass correlation coefficient (ICC) and associated 95% confidence interval (95% CI), coefficient of variation (CV), standard error of measurement (SEM), and minimal detectable change (MDC) across the measurement days and investigators. Results For PT measurements at rest and maximal load, the estimated ICCs for stiffness and length were ≥.867 and ≥.970, respectively, with 95% CIs ranging from poor (.306) to excellent (.973) and good (.897) to excellent (.999). The CV, SEM, and MDC for PT stiffness and length were ≤5.2% and ≤2.0%, ≤39.3 N/m and ≤0.9 mm, and ≤108.9 N/m and ≤2.6 mm, respectively. For AT measurements, some restrictions were evident for stiffness at rest and both parameters at maximal load. However, regarding AT length at rest, the estimated ICC was ≥.996, with an excellent 95% CI (.987-.999). The CV, SEM, and MDC for AT length at rest were 2.8%, ≤1.1 mm, and ≤2.9 mm, respectively. Conclusion The estimated ICCs show good to excellent reliability for the myotonometry method and the EFOV-US technique for measuring PT stiffness and length at rest and maximal load for experienced and novice investigators. However, some restrictions are evident for the AT, especially for measurements at maximal load.
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Affiliation(s)
- Florian Wegener
- Movement and Training Science, Faculty of Sport Science, Leipzig University, Leipzig, Germany
| | - Arne Ritterbusch
- Movement and Training Science, Faculty of Sport Science, Leipzig University, Leipzig, Germany
| | - Christian Saal
- Movement and Training Science, Faculty of Sport Science, Leipzig University, Leipzig, Germany
| | - Christian Baumgart
- Department of Movement and Training Science, Faculty of Humanities and Social Sciences, University of Wuppertal, Wuppertal, Germany
| | - Matthias W. Hoppe
- Department of Exercise Science, Institute of Sport Science and Motology, Faculty of Educational Sciences, Philipps University of Marburg, Marburg, Germany
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Yeung CYC, Svensson RB, Mogensen NMB, Merkel MFR, Schjerling P, Jokipii-Utzon A, Zhang C, Carstensen H, Buhl R, Kjaer M. Mechanical properties, collagen and glycosaminoglycan content of equine superficial digital flexor tendons are not affected by training. J Anat 2024. [PMID: 38712668 DOI: 10.1111/joa.14051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 04/09/2024] [Accepted: 04/12/2024] [Indexed: 05/08/2024] Open
Abstract
Physical activity can activate extracellular matrix (ECM) protein synthesis and influence the size and mechanical properties of tendon. In this study, we aimed to investigate whether different training histories of horses would influence the synthesis of collagen and other matrix proteins and alter the mechanical properties of tendon. Samples from superficial digital flexor tendon (SDFT) from horses that were either (a) currently race trained (n = 5), (b) previously race trained (n = 5) or (c) untrained (n = 4) were analysed for matrix protein abundance (mass spectrometry), collagen and glycosaminoglycan (GAG) content, ECM gene expression and mechanical properties. It was found that ECM synthesis by tendon fibroblasts in vitro varied depending upon the previous training history. In contrast, fascicle morphology, collagen and GAG content, mechanical properties and ECM gene expression of the tendon did not reveal any significant differences between groups. In conclusion, although we could not identify any direct impact of the physical training history on the mechanical properties or major ECM components of the tendon, it is evident that horse tendon cells are responsive to loading in vivo, and the training background may lead to a modification in the composition of newly synthesised matrix.
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Affiliation(s)
- Ching-Yan Chloé Yeung
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - René B Svensson
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Nikoline M B Mogensen
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Max F R Merkel
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schjerling
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Anja Jokipii-Utzon
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Cheng Zhang
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Helena Carstensen
- Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rikke Buhl
- Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kjaer
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark
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Oorloff M, Hruby A, Averbukh M, Alcala A, Dutta N, Torres TC, Moaddeli D, Vega M, Kim J, Bong A, Coakley AJ, Hicks D, Wang J, Wang T, Hoang S, Tharp KM, Garcia G, Higuchi-Sanabria R. Mechanical stress through growth on stiffer substrates impacts animal health and longevity in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.11.589121. [PMID: 38645203 PMCID: PMC11030433 DOI: 10.1101/2024.04.11.589121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Mechanical stress is a measure of internal resistance exhibited by a body or material when external forces, such as compression, tension, bending, etc. are applied. The study of mechanical stress on health and aging is a continuously growing field, as major changes to the extracellular matrix and cell-to-cell adhesions can result in dramatic changes to tissue stiffness during aging and diseased conditions. For example, during normal aging, many tissues including the ovaries, skin, blood vessels, and heart exhibit increased stiffness, which can result in a significant reduction in function of that organ. As such, numerous model systems have recently emerged to study the impact of mechanical and physical stress on cell and tissue health, including cell-culture conditions with matrigels and other surfaces that alter substrate stiffness and ex vivo tissue models that can apply stress directly to organs like muscle or tendons. Here, we sought to develop a novel method in an in vivo, model organism setting to study the impact of mechanical stress on aging, by increasing substrate stiffness in solid agar medium of C. elegans . To our surprise, we found shockingly limited impact of growth of C. elegans on stiffer substrates, including limited effects on cellular health, gene expression, organismal health, stress resilience, and longevity. Overall, our studies reveal that altering substrate stiffness of growth medium for C. elegans have only mild impact on animal health and longevity; however, these impacts were not nominal and open up important considerations for C. elegans biologists in standardizing agar medium choice for experimental assays.
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Lazarczuk SL, Collings TJ, Hams AH, Timmins RG, Opar DA, Edwards S, Shield AJ, Barrett RS, Bourne MN. Biceps femoris long head muscle and aponeurosis geometry in males with and without a history of hamstring strain injury. Scand J Med Sci Sports 2024; 34:e14619. [PMID: 38572910 DOI: 10.1111/sms.14619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 02/04/2024] [Accepted: 03/13/2024] [Indexed: 04/05/2024]
Abstract
OBJECTIVES Hamstring strain injuries (HSIs) commonly affect the proximal biceps femoris long head (BFlh) musculotendinous junction. Biomechanical modeling suggests narrow proximal BFlh aponeuroses and large muscle-to-aponeurosis width ratios increase localized tissue strains and presumably risk of HSI. This study aimed to determine if BFlh muscle and proximal aponeurosis geometry differed between limbs with and without a history of HSI. METHODS Twenty-six recreationally active males with (n = 13) and without (n = 13) a history of unilateral HSI in the last 24 months underwent magnetic resonance imaging of both thighs. BFlh muscle and proximal aponeurosis cross-sectional areas, length, volume, and interface area between muscle and aponeurosis were extracted. Previously injured limbs were compared to uninjured contralateral and control limbs for discrete variables and ratios, and along the relative length of tissues using statistical parametric mapping. RESULTS Previously injured limbs displayed significantly smaller muscle-to-aponeurosis volume ratios (p = 0.029, Wilcoxon effect size (ES) = 0.43) and larger proximal BFlh aponeurosis volumes (p = 0.019, ES = 0.46) than control limbs with no history of HSI. No significant differences were found between previously injured and uninjured contralateral limbs for any outcome measure (p = 0.216-1.000, ES = 0.01-0.36). CONCLUSIONS Aponeurosis geometry differed between limbs with and without a history of HSI. The significantly larger BFlh proximal aponeuroses and smaller muscle-to-aponeurosis volume ratios in previously injured limbs could alter the strain experienced in muscle adjacent to the musculotendinous junction during active lengthening. Future research is required to determine if geometric differences influence the risk of re-injury and whether they can be altered via targeted training.
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Affiliation(s)
- Stephanie L Lazarczuk
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Tyler J Collings
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Andrea H Hams
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Ryan G Timmins
- School of Behavioural and Health Sciences, Australian Catholic University, Brisbane, Queensland, Australia
- Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Melbourne, Victoria, Australia
| | - David A Opar
- Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Melbourne, Victoria, Australia
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, Victoria, Australia
| | - Suzi Edwards
- Discipline of Exercise and Sport Science, Faculty of Medicine and Health, The University of Sydney, Camperdown, New South Wales, Australia
- School of Environmental and Life Sciences, The University of Newcastle, Newcastle, New South Wales, Australia
| | - Anthony J Shield
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Rod S Barrett
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Matthew N Bourne
- School of Health Sciences and Social Work, Griffith University, Gold Coast, Queensland, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
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Llanos-Lagos C, Ramirez-Campillo R, Moran J, Sáez de Villarreal E. Effect of Strength Training Programs in Middle- and Long-Distance Runners' Economy at Different Running Speeds: A Systematic Review with Meta-analysis. Sports Med 2024; 54:895-932. [PMID: 38165636 PMCID: PMC11052887 DOI: 10.1007/s40279-023-01978-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2023] [Indexed: 01/04/2024]
Abstract
BACKGROUND Running economy is defined as the energy demand at submaximal running speed, a key determinant of overall running performance. Strength training can improve running economy, although the magnitude of its effect may depend on factors such as the strength training method and the speed at which running economy is assessed. AIM To compare the effect of different strength training methods (e.g., high loads, plyometric, combined methods) on the running economy in middle- and long-distance runners, over different running speeds, through a systematic review with meta-analysis. METHODS A systematic search was conducted across several electronic databases including Web of Science, PubMed, SPORTDiscus, and SCOPUS. Using different keywords and Boolean operators for the search, all articles indexed up to November 2022 were considered for inclusion. In addition, the PICOS criteria were applied: Population: middle- and long-distance runners, without restriction on sex or training/competitive level; Intervention: application of a strength training method for ≥ 3 weeks (i.e., high loads (≥ 80% of one repetition maximum); submaximal loads [40-79% of one repetition maximum); plyometric; isometric; combined methods (i.e., two or more methods); Comparator: control group that performed endurance running training but did not receive strength training or received it with low loads (< 40% of one repetition maximum); Outcome: running economy, measured before and after a strength training intervention programme; Study design: randomized and non-randomized controlled studies. Certainty of evidence was assessed with the GRADE approach. A three-level random-effects meta-analysis and moderator analysis were performed using R software (version 4.2.1). RESULTS The certainty of the evidence was found to be moderate for high load training, submaximal load training, plyometric training and isometric training methods and low for combined methods. The studies included 195 moderately trained, 272 well trained, and 185 highly trained athletes. The strength training programmes were between 6 and 24 weeks' duration, with one to four sessions executed per week. The high load and combined methods induced small (ES = - 0.266, p = 0.039) and moderate (ES = - 0.426, p = 0.018) improvements in running economy at speeds from 8.64 to 17.85 km/h and 10.00 to 14.45 km/h, respectively. Plyometric training improved running economy at speeds ≤ 12.00 km/h (small effect, ES = - 0.307, p = 0.028, β1 = 0.470, p = 0.017). Compared to control groups, no improvement in running economy (assessed speed: 10.00 to 15.28 and 9.75 to 16.00 km/h, respectively) was noted after either submaximal or isometric strength training (all, p > 0.131). The moderator analyses showed that running speed (β1 = - 0.117, p = 0.027) and VO2max (β1 = - 0.040, p = 0.020) modulated the effect of high load strength training on running economy (i.e., greater improvements at higher speeds and higher VO2max). CONCLUSIONS Compared to a control condition, strength training with high loads, plyometric training, and a combination of strength training methods may improve running economy in middle- and long-distance runners. Other methods such as submaximal load training and isometric strength training seem less effective to improve running economy in this population. Of note, the data derived from this systematic review suggest that although both high load training and plyometric training may improve running economy, plyometric training might be effective at lower speeds (i.e., ≤ 12.00 km/h) and high load strength training might be particularly effective in improving running economy (i) in athletes with a high VO2max, and (ii) at high running speeds. PROTOCOL REGISTRATION The original protocol was registered ( https://osf.io/gyeku ) at the Open Science Framework.
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Affiliation(s)
- Cristian Llanos-Lagos
- Physical Performance Sports Research Center (PPSRC), Universidad Pablo de Olavide, 41704, Seville, Spain
| | - Rodrigo Ramirez-Campillo
- Exercise and Rehabilitation Sciences Institute, School of Physical Therapy, Faculty of Rehabilitation Sciences, Universidad Andres Bello, 7591538, Santiago, Chile
| | - Jason Moran
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, Essex, CO43SQ, UK
| | - Eduardo Sáez de Villarreal
- Physical Performance Sports Research Center (PPSRC), Universidad Pablo de Olavide, 41704, Seville, Spain.
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Tsai MS, Domroes T, Pentidis N, Koschinski S, Schroll A, Bohm S, Arampatzis A, Mersmann F. Effect of the temporal coordination and volume of cyclic mechanical loading on human Achilles tendon adaptation in men. Sci Rep 2024; 14:6875. [PMID: 38519507 PMCID: PMC10960029 DOI: 10.1038/s41598-024-56840-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 03/12/2024] [Indexed: 03/25/2024] Open
Abstract
Human tendons adapt to mechanical loading, yet there is little information on the effect of the temporal coordination of loading and recovery or the dose-response relationship. For this reason, we assigned adult men to either a control or intervention group. In the intervention group, the two legs were randomly assigned to one of five high-intensity Achilles tendon (AT) loading protocols (i.e., 90% maximum voluntary contraction and approximately 4.5 to 6.5% tendon strain) that were systematically modified in terms of loading frequency (i.e., sessions per week) and overall loading volume (i.e., total time under loading). Before, at mid-term (8 weeks) and after completion of the 16 weeks intervention, AT mechanical properties were determined using a combination of inverse dynamics and ultrasonography. The cross-sectional area (CSA) and length of the free AT were measured using magnetic resonance imaging pre- and post-intervention. The data analysis with a linear mixed model showed significant increases in muscle strength, rest length-normalized AT stiffness, and CSA of the free AT in the intervention group (p < 0.05), yet with no marked differences between protocols. No systematic effects were found considering the temporal coordination of loading and overall loading volume. In all protocols, the major changes in normalized AT stiffness occurred within the first 8 weeks and were mostly due to material rather than morphological changes. Our findings suggest that-in the range of 2.5-5 sessions per week and 180-300 s total high strain loading-the temporal coordination of loading and recovery and overall loading volume is rather secondary for tendon adaptation.
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Affiliation(s)
- Meng-Shiuan Tsai
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Theresa Domroes
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Nikolaos Pentidis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Sophia Koschinski
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Arno Schroll
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.
- Berlin School of Movement Science, Berlin, Germany.
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Obst SJ, Peterson B, Heales LJ. Maximal Lower Limb Strength in Patellar Tendinopathy: A Systematic Review With Meta-Analysis. J Athl Train 2024; 59:159-172. [PMID: 37071550 PMCID: PMC10895401 DOI: 10.4085/1062-6050-0662.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
OBJECTIVE To investigate whether lower limb strength is reduced in people with patellar tendinopathy (PT) compared with asymptomatic control individuals or the asymptomatic contralateral limb. DATA SOURCES MEDLINE, PubMed, Scopus, and Web of Science. STUDY SELECTION To be included in the systematic review and meta-analysis, studies were required to be peer reviewed, published in the English language, and case control investigations; include participants with a clinical diagnosis of PT and an asymptomatic control or contralateral limb group; and include an objective measure of lower limb maximal strength. DATA EXTRACTION We extracted descriptive statistics for maximal strength for the symptomatic and asymptomatic limbs of individuals with PT and the limb(s) of the asymptomatic control group, inferential statistics for between-groups differences, participant characteristics, and details of the strength-testing protocol. The risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool for analytical cross-sectional studies. DATA SYNTHESIS Of the 23 included studies, 21 reported knee strength, 3 reported hip strength, and 1 reported ankle strength. Random-effects models (Hedges g) were used to calculate the pooled effect sizes (ESs) of muscle strength according to the direction of joint movement and type of contraction. The pooled ESs (95% CI) for maximal voluntary isometric contraction knee-extension strength, concentric knee-extension strength, and concentric knee-flexion strength were 0.54 (0.27, 0.80), 0.78 (0.30, 1.33), and 0.41 (0.04, 0.78), respectively, with all favoring greater strength in the asymptomatic control group. Researchers of 2 studies described maximal eccentric knee-extensor strength with no differences between the PT and asymptomatic control groups. In 3 studies, researchers measured maximal hip strength (abduction, extension, and external rotation), and all within-study ESs favored greater strength in the asymptomatic control group. CONCLUSIONS Isometric and concentric knee-extensor strength are reduced in people with PT compared with asymptomatic control individuals. In contrast, evidence for reduced eccentric knee-extension strength in people with PT compared with asymptomatic control individuals is limited and inconsistent. Although evidence is emerging that both knee-flexion and hip strength may be reduced in people with PT, more examination is needed to confirm this observation.
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Affiliation(s)
- Steven J Obst
- Musculoskeletal Health and Rehabilitation Research Group, School of Health, Medical and Applied Sciences, Central Queensland University, Bundaberg, Australia
| | - Benjamin Peterson
- Musculoskeletal Health and Rehabilitation Research Group, School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
| | - Luke J Heales
- Musculoskeletal Health and Rehabilitation Research Group, School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
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8
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Hagen M, Chebly J, Dhaen B, Fassian N, Salvalaggio M, Catelli DS, Verschueren S, Vanrenterghem J. Peak patellar tendon force progressions during heavy load single-leg squats on level ground and decline board. Clin Biomech (Bristol, Avon) 2024; 112:106179. [PMID: 38219457 DOI: 10.1016/j.clinbiomech.2024.106179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 01/16/2024]
Abstract
BACKGROUND Progressive tendon loading programs for patellar tendinopathy typically include single-leg squats with heavy weights either on level ground or on a decline board. Changes in patellar tendon force due to variations of the heavy load single-leg squat have not yet been objectively quantified. The objective of this study was to investigate the influence of the mass of an external weight and the use of a decline board on the peak patellar tendon force during a heavy load single-leg squat. METHODS Twelve healthy participants performed single-leg back squats on a decline board and level ground at 70%, 80% and 90% of their one repetition maximum. Three-dimensional kinematics and ground reaction forces were measured and the peak patellar tendon force was calculated using musculoskeletal modelling. A two-way repeated measures ANOVA determined the main effects for the mass of the external weights and the use of a decline board as well as their interaction effect. FINDINGS Peak patellar tendon forces were significantly higher on the decline board compared to level ground (p < 0.05). Neither on the decline board, nor on level ground did the peak patellar tendon force increase significantly when increasing the external weights (p > 0.05). INTERPRETATION Progression in peak patellar tendon forces during a heavy load single-leg squat can only be obtained with a decline board. Increasing the mass of the external weight from 70% to 90% of the one repetition maximum does not result in a progressively higher peak patellar tendon force.
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Affiliation(s)
- Michiel Hagen
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium.
| | - Joanna Chebly
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | - Bram Dhaen
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | - Noah Fassian
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | | | - Danilo S Catelli
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium; Department of Movement Sciences, KU Leuven, Leuven, Belgium
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Davids CJ, Roberts LA, Bjørnsen T, Peake JM, Coombes JS, Raastad T. Where Does Blood Flow Restriction Fit in the Toolbox of Athletic Development? A Narrative Review of the Proposed Mechanisms and Potential Applications. Sports Med 2023; 53:2077-2093. [PMID: 37578669 PMCID: PMC10587223 DOI: 10.1007/s40279-023-01900-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2023] [Indexed: 08/15/2023]
Abstract
Blood flow-restricted exercise is currently used as a low-intensity time-efficient approach to reap many of the benefits of typical high-intensity training. Evidence continues to lend support to the notion that even highly trained individuals, such as athletes, still benefit from this mode of training. Both resistance and endurance exercise may be combined with blood flow restriction to provide a spectrum of adaptations in skeletal muscle, spanning from myofibrillar to mitochondrial adjustments. Such diverse adaptations would benefit both muscular strength and endurance qualities concurrently, which are demanded in athletic performance, most notably in team sports. Moreover, recent work indicates that when traditional high-load resistance training is supplemented with low-load, blood flow-restricted exercise, either in the same session or as a separate training block in a periodised programme, a synergistic and complementary effect on training adaptations may occur. Transient reductions in mechanical loading of tissues afforded by low-load, blood flow-restricted exercise may also serve a purpose during de-loading, tapering or rehabilitation of musculoskeletal injury. This narrative review aims to expand on the current scientific and practical understanding of how blood flow restriction methods may be applied by coaches and practitioners to enhance current athletic development models.
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Affiliation(s)
- Charlie J Davids
- Sport, Performance, and Nutrition Research Group, School of Allied Health, Human Services and Sport, La Trobe University, Melbourne, Australia.
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia.
- Sport Performance Innovation and Knowledge Excellence (SPIKE), Queensland Academy of Sport, Brisbane, QLD, Australia.
| | - Llion A Roberts
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia
- Sport Performance Innovation and Knowledge Excellence (SPIKE), Queensland Academy of Sport, Brisbane, QLD, Australia
- School of Health Sciences and Social Work, Griffith University, Gold Coast, QLD, Australia
| | - Thomas Bjørnsen
- Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway
- Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
| | - Jonathan M Peake
- Sport Performance Innovation and Knowledge Excellence (SPIKE), Queensland Academy of Sport, Brisbane, QLD, Australia
- School of Biomedical Science, Queensland University of Technology, Brisbane, QLD, Australia
| | - Jeff S Coombes
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Truls Raastad
- Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
- Department of Physical Performance, Norwegian School of Sport Science, Oslo, Norway
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Adam NC, Smith CR, Herzog W, Amis AA, Arampatzis A, Taylor WR. In Vivo Strain Patterns in the Achilles Tendon During Dynamic Activities: A Comprehensive Survey of the Literature. SPORTS MEDICINE - OPEN 2023; 9:60. [PMID: 37466866 DOI: 10.1186/s40798-023-00604-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 07/02/2023] [Indexed: 07/20/2023]
Abstract
Achilles' tendon (AT) injuries such as ruptures and tendinopathies have experienced a dramatic rise in the mid- to older-aged population. Given that the AT plays a key role at all stages of locomotion, unsuccessful rehabilitation after injury often leads to long-term, deleterious health consequences. Understanding healthy in vivo strains as well as the complex muscle-tendon unit interactions will improve access to the underlying aetiology of injuries and how their functionality can be effectively restored post-injury. The goals of this survey of the literature with a systematic search were to provide a benchmark of healthy AT strains measured in vivo during functional activities and identify the sources of variability observed in the results. Two databases were searched, and all articles that provided measured in vivo peak strains or the change in strain with respect to time were included. In total, 107 articles that reported subjects over the age of 18 years with no prior AT injury and measured while performing functional activities such as voluntary contractions, walking, running, jumping, or jump landing were included in this review. In general, unclear anatomical definitions of the sub-tendon and aponeurosis structures have led to considerable confusion in the literature. MRI, ultrasound, and motion capture were the predominant approaches, sometimes coupled with modelling. The measured peak strains increased from 4% to over 10% from contractions, to walking, running, and jumping, in that order. Importantly, measured AT strains were heavily dependent on measurement location, measurement method, measurement protocol, individual AT geometry, and mechanical properties, as well as instantaneous kinematics and kinetics of the studied activity. Through a comprehensive review of approaches and results, this survey of the literature therefore converges to a united terminology of the structures and their common underlying characteristics and presents the state-of-knowledge on their functional strain patterns.
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Affiliation(s)
- Naomi C Adam
- Institute for Biomechanics, ETH Zürich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland
| | - Colin R Smith
- Institute for Biomechanics, ETH Zürich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, Calgary, Canada
| | - Andrew A Amis
- Department of Mechanical Engineering, Imperial College London, London, UK
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, and Berlin School of Movement Science, Berlin, Germany
| | - William R Taylor
- Institute for Biomechanics, ETH Zürich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland.
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11
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Fryar C, Tilley D, Casey E, Vincent H. A Research and Clinical Framework for Understanding Achilles Injury in Female Collegiate Gymnasts. Curr Sports Med Rep 2023; 22:260-267. [PMID: 37417663 DOI: 10.1249/jsr.0000000000001082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
ABSTRACT Gymnastics is a popular sport with a high injury rate, particularly at the collegiate level. Achilles tendon rupture is a catastrophic injury with career-changing impact. Over the last decade, there has been a growing incidence of Achilles tendon ruptures, especially in female gymnasts. Currently, neither the effects of contributing risk factors on Achilles tendon rupture nor the research frameworks to guide future intervention strategies have been well described. This article reviews the functional anatomy and mechanical properties of the Achilles tendon, provides precollegiate and collegiate intrinsic and extrinsic risk factors for Achilles tendon rupture, and proposes a research framework to address this injury from a systemic perspective. Potential clinical interventions to mitigate Achilles tendon injury are proposed based on currently available peer-reviewed evidence.
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Affiliation(s)
- Caroline Fryar
- Department of Physical Medicine and Rehabilitation, University of Florida College of Medicine, Gainesville, FL
| | - Dave Tilley
- Champion Physical Therapy & Performance, Watham, MA
| | - Ellen Casey
- Department of Physiatry, Hospital for Special Surgery, New York, NY
| | - Heather Vincent
- University of Florida College of Medicine, UF Physical Medicine & Rehabilitation
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12
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Finni T, Vanwanseele B. Towards modern understanding of the Achilles tendon properties in human movement research. J Biomech 2023; 152:111583. [PMID: 37086579 DOI: 10.1016/j.jbiomech.2023.111583] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/21/2023] [Accepted: 04/04/2023] [Indexed: 04/24/2023]
Abstract
The Achilles tendon (AT) is the strongest tendon in humans, yet it often suffers from injury. The mechanical properties of the AT afford efficient movement, power amplification and power attenuation during locomotor tasks. The properties and the unique structure of the AT as a common tendon for three muscles have been studied frequently in humans using in vivo methods since 1990's. As a part of the celebration of 50 years history of the International Society of Biomechanics, this paper reviews the history of the AT research focusing on its mechanical properties in humans. The questions addressed are: What are the most important mechanical properties of the Achilles tendon, how are they studied, what is their significance to human movement, and how do they adapt? We foresee that the ongoing developments in experimental methods and modeling can provide ways to advance knowledge of the complex three-dimensional structure and properties of the Achilles tendon in vivo, and to enable monitoring of the loading and recovery for optimizing individual adaptations.
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Affiliation(s)
- Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Finland.
| | - Benedicte Vanwanseele
- Faculty of Movement and Rehabilitation Science, Human Movement Biomechanics Research Group, KU Leuven, Belgium
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Sánchez Pastor A, García-Sánchez C, Marquina Nieto M, de la Rubia A. Influence of Strength Training Variables on Neuromuscular and Morphological Adaptations in Prepubertal Children: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4833. [PMID: 36981742 PMCID: PMC10049541 DOI: 10.3390/ijerph20064833] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Strength training in prepubertal children is one of the topics that has aroused the most interest and controversy among training professionals in recent years. Therefore, the aim of the present study was to analyze the available scientific evidence on the influence of strength training variables on morphological and/or neuromuscular adaptations in healthy prepubertal populations with no previous experience in this type of training according to the descriptive sample characteristics. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, 22 studies were selected after a systematic search and selection process using four electronic databases: Google Scholar, PubMed, Scopus, and SPORT Discus. Furthermore, the internal validity of the studies included was assessed using the modified PEDro scale. The sample consisted of 604 prepubertal children (age, 10.02 ± 0.75 years), of whom 473 were boys and 131 were girls, with 104 strength training programs recorded. Strength training resulted in a significant increase in jumping (n = 29) and sprinting (n = 13) abilities. Moreover, muscle strength was increased in 100% of the cases. Morphologically, strength training resulted in a decrease in body fat percentage (n = 19) and an increase in lean body mass (n = 17). With regard to gender, increases in general sport skills and basic physical abilities were significant in males but not in females. Thus, the results are more heterogeneous in girls due to the small number of studies carried out. Therefore, this research provides practical applications for coaches to design and implement more effective training programs to maximize adaptations, enhance physical performance, and reduce injury risk.
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Affiliation(s)
- Alberto Sánchez Pastor
- Facultad de Ciencias de la Actividad Física y del Deporte, Universidad Politécnica de Madrid, Calle Martín Fierro 7, 28040 Madrid, Spain
| | - Carlos García-Sánchez
- Deporte y Entrenamiento Research Group, Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte, Universidad Politécnica de Madrid, Calle Martín Fierro 7, 28040 Madrid, Spain
| | - Moisés Marquina Nieto
- Deporte y Entrenamiento Research Group, Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte, Universidad Politécnica de Madrid, Calle Martín Fierro 7, 28040 Madrid, Spain
| | - Alfonso de la Rubia
- Deporte y Entrenamiento Research Group, Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte, Universidad Politécnica de Madrid, Calle Martín Fierro 7, 28040 Madrid, Spain
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de Sousa AMM, Cavalcante JGT, Bottaro M, Vieira DCL, Babault N, Geremia JM, Corrigan P, Silbernagel KG, Durigan JLQ, Marqueti RDC. The Influence of Hip and Knee Joint Angles on Quadriceps Muscle-Tendon Unit Properties during Maximal Voluntary Isometric Contraction. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3947. [PMID: 36900958 PMCID: PMC10002253 DOI: 10.3390/ijerph20053947] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
Determining how the quadriceps femoris musculotendinous unit functions, according to hip and knee joint angles, may help with clinical decisions when prescribing knee extension exercises. We aimed to determine the effect of hip and knee joint angles on structure and neuromuscular functioning of all constituents of the quadriceps femoris and patellar tendon properties. Twenty young males were evaluated in four positions: seated and supine in both 20° and 60° of knee flexion (SIT20, SIT60, SUP20, and SUP60). Peak knee extension torque was determined during maximal voluntary isometric contraction (MVIC). Ultrasound imaging was used at rest and during MVIC to characterize quadriceps femoris muscle and tendon aponeurosis complex stiffness. We found that peak torque and neuromuscular efficiency were higher for SUP60 and SIT60 compared to SUP20 and SIT20 position. We found higher fascicle length and lower pennation angle in positions with the knee flexed at 60°. The tendon aponeurosis complex stiffness, tendon force, stiffness, stress, and Young's modulus seemed greater in more elongated positions (60°) than in shortened positions (20°). In conclusion, clinicians should consider positioning at 60° of knee flexion rather than 20°, regardless if seated or supine, during rehabilitation to load the musculotendinous unit enough to stimulate a cellular response.
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Affiliation(s)
- Alessandra Martins Melo de Sousa
- Laboratory of Muscle and Tendon Plasticity, Graduate Program of Rehabilitation Sciences, University of Brasília, Brasília 72220275, Brazil
| | | | - Martim Bottaro
- College of Physical Education, University of Brasília, Brasília 70910900, Brazil
| | - Denis César Leite Vieira
- College of Physical Education, University of Brasília, Brasília 70910900, Brazil
- Centre d’Expertise de la Performance, INSERM U1093 CAPS, Sports Science Faculty, University of Burgundy, 21078 Dijon, France
| | - Nicolas Babault
- Centre d’Expertise de la Performance, INSERM U1093 CAPS, Sports Science Faculty, University of Burgundy, 21078 Dijon, France
| | - Jeam Marcel Geremia
- Exercise Research Laboratory, School of Physical Education, Physical Therapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre 90690200, Brazil
| | - Patrick Corrigan
- Department of Physical Therapy and Athletic Training, Saint Louis University, St. Louis, MO 63104, USA
| | | | - João Luiz Quaglioti Durigan
- Laboratory of Muscle and Tendon Plasticity, Graduate Program of Rehabilitation Sciences, University of Brasília, Brasília 72220275, Brazil
| | - Rita de Cássia Marqueti
- Laboratory of Molecular Analysis, Graduate Program of Rehabilitation Sciences, University of Brasília, Brasília 72220275, Brazil
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15
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Radovanović G, Bohm S, Arampatzis A, Legerlotz K. In Achilles Tendinopathy the Symptomatic Tendon Differs from the Asymptomatic Tendon While Exercise Therapy Has Little Effect on Asymmetries-An Ancillary Analysis of Data from a Controlled Clinical Trial. J Clin Med 2023; 12:jcm12031102. [PMID: 36769750 PMCID: PMC9918090 DOI: 10.3390/jcm12031102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/27/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND As inter-limb asymmetries can be associated with higher injury risk, we aimed to investigate their role in Achilles tendinopathy patients. METHODS In Achilles tendinopathy patients (n = 41), we assessed inter-limb asymmetries of mechanical, material, and morphological musculoskeletal properties and function and how those were affected by 12 weeks of exercise intervention (high-load protocol, n = 13; Alfredson protocol, n = 11). Moreover, we assessed whether asymmetry reductions correlated with improved Patient-Reported Outcomes (VISA-A score). RESULTS At baseline, tendinopathic tendons demonstrated lower tendon force (p = 0.017), lower tendon stress (p < 0.0001), larger tendon cross-sectional area (CSA) (p < 0.001), and increased intratendinous (p = 0.042) and tendon overall (p = 0.021) vascularization. For the high-load group, PRE-to-POST asymmetry comparisons revealed an asymmetry increase for the counter-movement jump (CMJ) (p = 0.034) and PRE-to-POST VISA-A score improvements correlated with CSA asymmetry reductions (p = 0.024). Within the Alfredson group, PRE-to-POST VISA-A score improvements correlated with CMJ asymmetry reductions (p = 0.044) and tendon stiffness asymmetry increases (p = 0.037). POST-to-POST in-between group comparisons revealed lower asymmetry in the high-load group for tendon elongation (p = 0.021) and tendon strain (p = 0.026). CONCLUSIONS The tendinopathic limb differs from the asymptomatic limb while therapeutic exercise interventions have little effect on asymmetries. Asymmetry reductions are not necessarily associated with tendon health improvements.
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Affiliation(s)
- Goran Radovanović
- Movement Biomechanics, Institute of Sports Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
- Department Performance, Neuroscience, Therapy and Health, Faculty of Health Sciences, Medical School Hamburg—University of Applied Sciences and Medical University, 20457 Hamburg, Germany
- Institute of Interdisciplinary Exercise Science and Sports Medicine, Faculty of Health Sciences, Medical School Hamburg—University of Applied Sciences and Medical University, 20457 Hamburg, Germany
- Correspondence: ; Tel.: +49-030-2093-46052
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
| | - Kirsten Legerlotz
- Movement Biomechanics, Institute of Sports Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
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16
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Merry K, Napier C, Waugh CM, Scott A. Foundational Principles and Adaptation of the Healthy and Pathological Achilles Tendon in Response to Resistance Exercise: A Narrative Review and Clinical Implications. J Clin Med 2022; 11:4722. [PMID: 36012960 PMCID: PMC9410084 DOI: 10.3390/jcm11164722] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 12/03/2022] Open
Abstract
Therapeutic exercise is widely considered a first line fundamental treatment option for managing tendinopathies. As the Achilles tendon is critical for locomotion, chronic Achilles tendinopathy can have a substantial impact on an individual's ability to work and on their participation in physical activity or sport and overall quality of life. The recalcitrant nature of Achilles tendinopathy coupled with substantial variation in clinician-prescribed therapeutic exercises may contribute to suboptimal outcomes. Further, loading the Achilles tendon with sufficiently high loads to elicit positive tendon adaptation (and therefore promote symptom alleviation) is challenging, and few works have explored tissue loading optimization for individuals with tendinopathy. The mechanism of therapeutic benefit that exercise therapy exerts on Achilles tendinopathy is also a subject of ongoing debate. Resultingly, many factors that may contribute to an optimal therapeutic exercise protocol for Achilles tendinopathy are not well described. The aim of this narrative review is to explore the principles of tendon remodeling under resistance-based exercise in both healthy and pathologic tissues, and to review the biomechanical principles of Achilles tendon loading mechanics which may impact an optimized therapeutic exercise prescription for Achilles tendinopathy.
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Affiliation(s)
- Kohle Merry
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Christopher Napier
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Charlie M. Waugh
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Alex Scott
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
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