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J M Dick T, Tucker K, Hug F, Besomi M, van Dieën JH, Enoka RM, Besier T, Carson RG, Clancy EA, Disselhorst-Klug C, Falla D, Farina D, Gandevia S, Holobar A, Kiernan MC, Lowery M, McGill K, Merletti R, Perreault E, Rothwell JC, Søgaard K, Wrigley T, Hodges PW. Consensus for experimental design in electromyography (CEDE) project: Application of EMG to estimate muscle force. J Electromyogr Kinesiol 2024:102910. [PMID: 39069427 DOI: 10.1016/j.jelekin.2024.102910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/06/2024] [Accepted: 06/06/2024] [Indexed: 07/30/2024] Open
Abstract
Skeletal muscles power movement. Deriving the forces produced by individual muscles has applications across various fields including biomechanics, robotics, and rehabilitation. Since direct in vivo measurement of muscle force in humans is invasive and challenging, its estimation through non-invasive methods such as electromyography (EMG) holds considerable appeal. This matrix, developed by the Consensus for Experimental Design in Electromyography (CEDE) project, summarizes recommendations on the use of EMG to estimate muscle force. The matrix encompasses the use of bipolar surface EMG, high density surface EMG, and intra-muscular EMG (1) to identify the onset of muscle force during isometric contractions, (2) to identify the offset of muscle force during isometric contractions, (3) to identify force fluctuations during isometric contractions, (4) to estimate force during dynamic contractions, and (5) in combination with musculoskeletal models to estimate force during dynamic contractions. For each application, recommendations on the appropriateness of using EMG to estimate force and justification for each recommendation are provided. The achieved consensus makes clear that there are limited scenarios in which EMG can be used to accurately estimate muscle forces. In most cases, it remains important to consider the activation as well as the muscle state and other biomechanical and physiological factors- such as in the context of a formal mechanical model. This matrix is intended to encourage interdisciplinary discussions regarding the integration of EMG with other experimental techniques and to promote advances in the application of EMG towards developing muscle models and musculoskeletal simulations that can accurately predict muscle forces in healthy and clinical populations.
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Affiliation(s)
- Taylor J M Dick
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| | - Kylie Tucker
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| | - François Hug
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia; Université Côte d'Azur, LAMHESS, Nice, France
| | - Manuela Besomi
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia
| | - Jaap H van Dieën
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, Netherlands
| | - Roger M Enoka
- Department of Integrative Physiology, University of Colorado Boulder, CO, USA
| | - Thor Besier
- Auckland Bioengineering Institute and Department of Engineering Science & Biomedical Engineering, University of Auckland, Auckland, New Zealand
| | - Richard G Carson
- Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Dublin, Ireland; School of Psychology, Queen's University Belfast, Belfast, UK; School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
| | | | - Catherine Disselhorst-Klug
- Department of Rehabilitation and Prevention Engineering, Institute of Applied Medical Engineering, RWTH Aachen University, Aachen, Germany
| | - Deborah Falla
- Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, UK
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, UK
| | - Simon Gandevia
- Neuroscience Research Australia, University of New South Wales, Sydney, Australia
| | - Aleš Holobar
- Faculty of Electrical Engineering and Computer Science, University of Maribor, Koroška cesta 46, Maribor, Slovenia
| | - Matthew C Kiernan
- Brain and Mind Centre, University of Sydney, Sydney, Australia; Department of Neurology, Royal Prince Alfred Hospital, Sydney, Australia
| | - Madeleine Lowery
- School of Electrical and Electronic Engineering, University College Dublin, Belfield, Dublin, Ireland
| | | | - Roberto Merletti
- LISiN, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy
| | - Eric Perreault
- Northwestern University, Evanston, IL, USA; Shirley Ryan AbilityLab, Chicago, IL, USA
| | - John C Rothwell
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, London, UK
| | - Karen Søgaard
- Department of Clinical Research and Department of Sports Sciences and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Tim Wrigley
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, University of Melbourne, Parkville, Australia
| | - Paul W Hodges
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia.
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Létocart AJ, Svensson RB, Mabesoone F, Charleux F, Marin F, Dermigny Q, Magnusson SP, Couppé C, Grosset JF. Structure and function of Achilles and patellar tendons following moderate slow resistance training in young and old men. Eur J Appl Physiol 2024:10.1007/s00421-024-05461-y. [PMID: 38649478 DOI: 10.1007/s00421-024-05461-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 03/05/2024] [Indexed: 04/25/2024]
Abstract
The aim of this study was to investigate the effect of aging and resistance training with a moderate load on the size and mechanical properties of the patellar (PT) and Achilles tendon (AT) and their associated aponeuroses; medial gastrocnemius (MG) and vastus lateralis (VL). Young (Y55; 24.8 ± 3.8 yrs, n = 11) and old men (O55; 70.0 ± 4.6 yrs, n = 13) were assigned to undergo a training program (12 weeks; 3 times/week) of moderate slow resistance training [55% of one repetition maximum (RM)] of the triceps surae and quadriceps muscles. Tendon dimensions were assessed using 1.5 T magnetic resonance imaging before and after 12 weeks. AT and PT cross sectional area (CSA) were determined every 10% of tendon length. Mechanical properties of the free AT, MG aponeurosis, PT, and VL aponeurosis were assessed using ultrasonography (deformation) and tendon force measurements. CSA of the AT but not PT was greater in O55 compared with Y55. At baseline, mechanical properties were generally lower in O55 than Y55 for AT, MG aponeurosis and VL aponeurosis (Young's modulus) but not for PT. CSA of the AT and PT increased equally in both groups following training. Further, for a given force, stiffness and Young's modulus also increased equally for VL aponeurosis and AT, for boths groups. The present study highlights that except for the PT, older men have lower tendon (AT, MG aponeurosis, and VL aponeurosis) mechanical properties than young men and 12-weeks of moderate slow resistance training appears sufficient to improve tendon size and mechanical adaptations in both young and older men. New and Noteworthy: These novel findings suggest that short-term moderate slow resistance training induces equal improvements in tendon size and mechanics regardless of age.
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Affiliation(s)
- Adrien J Létocart
- UMR CNRS 7338 Biomécanique et Bioingénierie, Sorbonne Universités, Université de Technologie de Compiègne, 60205, Compiègne Cedex, France.
| | - René B Svensson
- Department of Physical and Occupational Therapy, Bispebjerg-Frederiksberg Hospitals, Copenhagen, Denmark
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Frédéric Marin
- UMR CNRS 7338 Biomécanique et Bioingénierie, Sorbonne Universités, Université de Technologie de Compiègne, 60205, Compiègne Cedex, France
| | - Quentin Dermigny
- UMR CNRS 7338 Biomécanique et Bioingénierie, Sorbonne Universités, Université de Technologie de Compiègne, 60205, Compiègne Cedex, France
| | - S Peter Magnusson
- Department of Physical and Occupational Therapy, Bispebjerg-Frederiksberg Hospitals, Copenhagen, Denmark
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Christian Couppé
- Department of Physical and Occupational Therapy, Bispebjerg-Frederiksberg Hospitals, Copenhagen, Denmark
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Jean-François Grosset
- UMR CNRS 7338 Biomécanique et Bioingénierie, Sorbonne Universités, Université de Technologie de Compiègne, 60205, Compiègne Cedex, France.
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3
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Bohm S, Schroll A, Mersmann F, Arampatzis A. Assessment and modelling of the activation-dependent shift in optimal length of the human soleus muscle in vivo. J Physiol 2024; 602:1371-1384. [PMID: 38482557 DOI: 10.1113/jp285986] [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: 11/22/2023] [Accepted: 02/23/2024] [Indexed: 04/04/2024] Open
Abstract
Previous in vitro and in situ studies have reported a shift in optimal muscle fibre length for force generation (L0) towards longer length at decreasing activation levels (also referred to as length-dependent activation), yet the relevance for in vivo human muscle contractions with a variable activation pattern remains largely unclear. By a combination of dynamometry, ultrasound and electromyography (EMG), we experimentally obtained muscle force-fascicle length curves of the human soleus at 100%, 60% and 30% EMGmax levels from 15 participants aiming to investigate activation-dependent shifts in L0 in vivo. The results showed a significant increase in L0 of 6.5 ± 6.0% from 100% to 60% EMGmax and of 9.1 ± 7.2% from 100% to 30% EMGmax (both P < 0.001), respectively, providing evidence of a moderate in vivo activation dependence of the soleus force-length relationship. Based on the experimental results, an approximation model of an activation-dependent force-length relationship was defined for each individual separately and for the collective data of all participants, both with sufficiently high accuracy (R2 of 0.899 ± 0.056 and R2 = 0.858). This individual approximation approach and the general approximation model outcome are freely accessible and may be used to integrate activation-dependent shifts in L0 in experimental and musculoskeletal modelling studies to improve muscle force predictions. KEY POINTS: The phenomenon of the activation-dependent shift in optimal muscle fibre length for force generation (length-dependent activation) is poorly understood for human muscle in vivo dynamic contractions. We experimentally observed a moderate shift in optimal fascicle length towards longer length at decreasing electromyographic activity levels for the human soleus muscle in vivo. Based on the experimental results, we developed a freely accessible approximation model that allows the consideration of activation-dependent shifts in optimal length in future experimental and musculoskeletal modelling studies to improve muscle force predictions.
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Affiliation(s)
- Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Arno Schroll
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, Berlin, Germany
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4
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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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Bohm S, Mersmann F, Schroll A, Arampatzis A. Speed-specific optimal contractile conditions of the human soleus muscle from slow to maximum running speed. J Exp Biol 2023; 226:jeb246437. [PMID: 37901934 DOI: 10.1242/jeb.246437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 10/13/2023] [Indexed: 10/31/2023]
Abstract
The soleus is the main muscle for propulsion during human running but its operating behavior across the spectrum of physiological running speeds is currently unknown. This study experimentally investigated the soleus muscle activation patterns and contractile conditions for force generation, power production and efficient work production (i.e. force-length potential, force-velocity potential, power-velocity potential and enthalpy efficiency) at seven running speeds (3.0 m s-1 to individual maximum). During submaximal running (3.0-6.0 m s-1), the soleus fascicles shortened close to optimal length and at a velocity close to the efficiency maximum, two contractile conditions for economical work production. At higher running speeds (7.0 m s-1 to maximum), the soleus muscle fascicles still operated near optimum length, yet the fascicle shortening velocity increased and shifted towards the optimum for mechanical power production with a simultaneous increase in muscle activation, providing evidence for three cumulative mechanisms to enhance mechanical power production. Using the experimentally determined force-length-velocity potentials and muscle activation as inputs in a Hill-type muscle model, a reduction in maximum soleus muscle force at speeds ≥7.0 m s-1 and a continuous increase in maximum mechanical power with speed were predicted. The reduction in soleus maximum force was associated with a reduced force-velocity potential. The increase in maximum power was explained by an enhancement of muscle activation and contractile conditions until 7.0 m s-1, but mainly by increased muscle activation at high to maximal running speed.
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Affiliation(s)
- Sebastian Bohm
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Falk Mersmann
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Arno Schroll
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Adamantios Arampatzis
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
- Berlin School of Movement Science, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
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Cunnane BT, Sinha U, Malis V, Hernandez RD, Smitaman E, Sinha S. Effect of different ankle joint positions on medial gastrocnemius muscle fiber strains during isometric plantarflexion. Sci Rep 2023; 13:14986. [PMID: 37696877 PMCID: PMC10495375 DOI: 10.1038/s41598-023-41127-z] [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: 02/03/2023] [Accepted: 08/22/2023] [Indexed: 09/13/2023] Open
Abstract
Muscle force production is influenced by muscle fiber and aponeurosis architecture. This prospective cohort study utilizes special MR imaging sequences to examine the structure-function in-vivo in the Medial Gastrocnemius (MG) at three-ankle angles (dorsiflexion, plantar flexion-low and high) and two sub-maximal levels of maximum voluntary contraction (25% and 50%MVC). The study was performed on 6 young male participants. Muscle fiber and aponeurosis strain, fiber strain normalized to force, fiber length and pennation angle (at rest and peak contraction) were analyzed for statistical differences between ankle positions and %MVC. A two-way repeated measures ANOVA and post hoc Bonferroni-adjusted tests were conducted for normal data. A related samples test with Friedman's 2-way ANOVA by ranks with corrections for multiple comparisons was conducted for non-normal data. The dorsiflexed ankle position generated significantly higher force with lower fiber strain than the plantarflexed positions. Sarcomere length extracted from muscle fiber length at each ankle angle was used to track the location on the Force-Length curve and showed the MG operates on the curve's ascending limb. Muscle force changes predicted from the F-L curve going from dorsi- to plantarflexion was less than that experimentally observed suggesting other determinants of force changes with ankle position.
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Affiliation(s)
| | - Usha Sinha
- Physics, San Diego State University, San Diego, CA, USA
| | - Vadim Malis
- Muscle Imaging and Modeling Lab, Dept. of Radiology, UC San Diego, 8939 Villa La Jolla, San Diego, CA, 92121, USA
| | | | | | - Shantanu Sinha
- Muscle Imaging and Modeling Lab, Dept. of Radiology, UC San Diego, 8939 Villa La Jolla, San Diego, CA, 92121, USA.
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Kassiano W, Costa B, Kunevaliki G, Soares D, Zacarias G, Manske I, Takaki Y, Ruggiero MF, Stavinski N, Francsuel J, Tricoli I, Carneiro MAS, Cyrino ES. Greater Gastrocnemius Muscle Hypertrophy After Partial Range of Motion Training Performed at Long Muscle Lengths. J Strength Cond Res 2023; 37:1746-1753. [PMID: 37015016 DOI: 10.1519/jsc.0000000000004460] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 11/02/2022] [Indexed: 04/06/2023]
Abstract
ABSTRACT Kassiano, W, Costa, B, Kunevaliki, G, Soares, D, Zacarias, G, Manske, I, Takaki, Y, Ruggiero, MF, Stavinski, N, Francsuel, J, Tricoli, I, Carneiro, MAS, and Cyrino, ES. Greater gastrocnemius muscle hypertrophy after partial range of motion training performed at long muscle lengths. J Strength Cond Res 37(9): 1746-1753, 2023-Whether there is an optimal range of motion (ROM) to induce muscle hypertrophy remains elusive, especially for gastrocnemius. This study aimed to compare the changes in gastrocnemius muscle thickness between calf raise exercise performed with full ROM (FULL ROM ), partial ROM performed in the initial (INITIAL ROM ), and final (FINAL ROM ) portions of the ROM. Forty-two young women performed a calf training program for 8 weeks, 3 days·week -1 , with differences in the calf raise ROM configuration. The calf raise exercise was performed in a pin-loaded, horizontal, leg-press machine, in 3 sets of 15-20 repetition maximum. The subjects were randomly assigned to 1 of the 3 groups: FULL ROM (ankle: -25° to +25°), INITIAL ROM (ankle: -25° to 0°), and FINAL ROM (ankle: 0° to +25°), where 0° was defined as an angle of 90° of the foot with the tibia. The muscle thickness measurements of medial and lateral gastrocnemius were taken by means of B-mode ultrasound. INITIAL ROM elicited greater medial gastrocnemius increases than FULL ROM and FINAL ROM (INITIAL ROM = +15.2% vs. FULL ROM = +6.7% and FINAL ROM = +3.4%; p ≤ 0.009). Furthermore, INITIAL ROM elicited greater lateral gastrocnemius increases than FINAL ROM (INITIAL ROM = +14.9% vs. FINAL ROM = +6.2%; p < 0.024) but did not significantly differ from FULL ROM (FULL ROM = +7.3%; p = 0.060). The current results suggest that calf training performed at longer muscle lengths may optimize gastrocnemius muscle hypertrophy in young women. Therefore, when prescribing hypertrophy-oriented training, the inclusion of the calf raise exercise performed with partial ROM in the initial portion of the excursion should be considered.
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Affiliation(s)
- Witalo Kassiano
- Metabolism, Nutrition and Exercise Laboratory, Physical Education and Sport Center, State University of Londrina, Londrina, Brazil
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Kovács B, Petridis L, Négyesi J, Sebestyén Ö, Jingyi Y, Zhang J, Gu Y, Tihanyi J. An Acute Transition from Rearfoot to Forefoot Strike does not Induce Major Changes in Plantarflexor Muscles Activation for Habitual Rearfoot Strike Runners. J Sports Sci Med 2023; 22:512-525. [PMID: 37711699 PMCID: PMC10499148 DOI: 10.52082/jssm.2023.512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 08/14/2023] [Indexed: 09/16/2023]
Abstract
Footstrike pattern has received increased attention within the running community because there is a common belief that forefoot strike running (FFS) is more advantageous (i.e., improve performance and reduce running injuries) than rearfoot strike running (RFS) in distance running. Literature reports suggest greater knee joint flexion magnitude and initial knee angle during stance in FFS compared with RFS running We examined the EMG activation of the triceps surae muscles during an acute transition from RFS to FFS strike. We tested the hypothesis that due to larger knee flexion in FFS the gastrocnemius muscles possibly decrease their EMG activity because muscle fascicles operate under unfavorable conditions. Fourteen competitive healthy middle- and long-distance runners who were habitual RFS runners ran on a treadmill at three speeds: 12, 14, and 16 km·h-1. Each running speed was performed with both FFS and RFS patterns. Lower limb kinematics in the sagittal plane and normalized electromyography (EMG) activity of medial gastrocnemius proximal, middle and distal regions, lateral gastrocnemius and soleus muscles were compared between footstrike patterns and running speeds across the stride cycle. Contrary to our expectations, the knee joint range of motion was similar in FFS and RFS running. However, the sagittal plane ankle joint motion was greater (p < 0.01) while running with FFS, resulting in a significantly greater muscle-tendon unit lengthening (p < 0.01) in FFS compared with RFS running. In addition, medial and lateral gastrocnemius showed higher EMG activity in FFS compared with RFS running in the late swing and early stance but only for a small percentage of the stride cycle. However, strike patterns and running speed failed to induce region-specific activation differences within the medial gastrocnemius muscle. Overall, well-trained RFS runners are able to change to FFS running by altering only the ankle joint kinematics without remarkably changing the EMG activity pattern.
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Affiliation(s)
- Bálint Kovács
- Ningbo University, Faculty of Sport Science, Ningbo, China
- Department of Kinesiology, Hungarian University of Sport Sciences, Budapest, Hungary
| | - Leonidas Petridis
- Research Centre for Sport Physiology, Hungarian University of Sport Sciences, Hungary
| | - János Négyesi
- Division of Biomedical Engineering for Health and Welfare, Tohoku University Graduate School of Biomedical Engineering, Sendai, Japan
| | - Örs Sebestyén
- Department of Kinesiology, Hungarian University of Sport Sciences, Budapest, Hungary
| | - Ye Jingyi
- Ningbo University, Faculty of Sport Science, Ningbo, China
| | - Jingfeng Zhang
- University of Chinese Academy of Sciences, Department of Radiology, HwaMei Hospital, Ningbo, China
| | - Yaodong Gu
- Ningbo University, Faculty of Sport Science, Ningbo, China
| | - József Tihanyi
- Department of Kinesiology, Hungarian University of Sport Sciences, Budapest, Hungary
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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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Kharazi M, Theodorakis C, Mersmann F, Bohm S, Arampatzis A. Contractile Work of the Soleus and Biarticular Mechanisms of the Gastrocnemii Muscles Increase the Net Ankle Mechanical Work at High Walking Speeds. BIOLOGY 2023; 12:872. [PMID: 37372156 DOI: 10.3390/biology12060872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/13/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023]
Abstract
Increasing walking speed is accompanied by an increase of the mechanical power and work performed at the ankle joint despite the decrease of the intrinsic muscle force potential of the soleus (Sol) and gastrocnemius medialis (GM) muscles. In the present study, we measured Achilles tendon (AT) elongation and, based on an experimentally determined AT force-elongation relationship, quantified AT force at four walking speeds (slow 0.7 m.s-1, preferred 1.4 m.s-1, transition 2.0 m.s-1, and maximum 2.6 ± 0.3 m.s-1). Further, we investigated the mechanical power and work of the AT force at the ankle joint and, separately, the mechanical power and work of the monoarticular Sol at the ankle joint and the biarticular gastrocnemii at the ankle and knee joints. We found a 21% decrease in maximum AT force at the two higher speeds compared to the preferred; however, the net work of the AT force at the ankle joint (ATF work) increased as a function of walking speed. An earlier plantar flexion accompanied by an increased electromyographic activity of the Sol and GM muscles and a knee-to-ankle joint energy transfer via the biarticular gastrocnemii increased the net ATF mechanical work by 1.7 and 2.4-fold in the transition and maximum walking speed, respectively. Our findings provide first-time evidence for a different mechanistic participation of the monoarticular Sol muscle (i.e., increased contractile net work carried out) and the biarticular gastrocnemii (i.e., increased contribution of biarticular mechanisms) to the speed-related increase of net ATF work.
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Affiliation(s)
- Mohamadreza Kharazi
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Berlin School of Movement Science, 10115 Berlin, Germany
| | - Christos Theodorakis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Berlin School of Movement Science, 10115 Berlin, Germany
| | - Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Berlin School of Movement Science, 10115 Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Berlin School of Movement Science, 10115 Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Berlin School of Movement Science, 10115 Berlin, Germany
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11
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Holzer D, Millard M, Hahn D, Siebert T, Schwirtz A, Seiberl W. Tendon compliance and preload must be considered when determining the in vivo force-velocity relationship from the torque-angular velocity relation. Sci Rep 2023; 13:6588. [PMID: 37085664 PMCID: PMC10121672 DOI: 10.1038/s41598-023-33643-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 04/16/2023] [Indexed: 04/23/2023] Open
Abstract
In vivo, the force-velocity relation (F-v-r) is typically derived from the torque-angular velocity relation (T-ω-r), which is subject to two factors that may influence resulting measurements: tendon compliance and preload prior to contraction. The in vivo plantar flexors' T-ω-r was determined during preloaded maximum voluntary shortening contractions at 0-200°/s. Additionally, we used a two factor block simulation study design to independently analyze the effects of preload and tendon compliance on the resulting T-ω-r. Therefore, we replicated the in vivo experiment using a Hill-type muscle model of the gastrocnemius medialis. The simulation results matched a key pattern observed in our recorded in vivo experimental data: during preloaded contractions, torque output of the muscle was increased when compared with non-preloaded contractions from literature. This effect increased with increasing contraction velocity and can be explained by a rapidly recoiling tendon, allowing the contractile element to contract more slowly, thus developing higher forces compared with non-preloaded contractions. Our simulation results also indicate that a more compliant tendon results in increased ankle joint torques. The simulation and the experimental data clearly show that the deduction of the in vivo F-v-r from the T-ω-r is compromised due to the two factors preloading and tendon compliance.
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Affiliation(s)
- Denis Holzer
- Biomechanics in Sports, Department of Sport and Health Sciences, Technical University of Munich, Georg-Brauchle-Ring 60/62, 80992, Munich, Germany.
| | - Matthew Millard
- Institute of Engineering and Computational Mechanics, University of Stuttgart, Stuttgart, Germany
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
| | - Daniel Hahn
- Human Movement Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
| | - Tobias Siebert
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
| | - Ansgar Schwirtz
- Biomechanics in Sports, Department of Sport and Health Sciences, Technical University of Munich, Georg-Brauchle-Ring 60/62, 80992, Munich, Germany
| | - Wolfgang Seiberl
- Biomechanics in Sports, Department of Sport and Health Sciences, Technical University of Munich, Georg-Brauchle-Ring 60/62, 80992, Munich, Germany
- Institute of Sport Science, Department of Human Sciences, Universität der Bundeswehr München, Neubiberg, Germany
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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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13
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Bennett EC, Machado E, Fletcher JR. How do differences in Achilles' tendon moment arm lengths affect muscle-tendon dynamics and energy cost during running? Front Sports Act Living 2023; 5:1125095. [PMID: 37139299 PMCID: PMC10150092 DOI: 10.3389/fspor.2023.1125095] [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: 12/15/2022] [Accepted: 03/24/2023] [Indexed: 05/05/2023] Open
Abstract
Introduction The relationship between the Achilles tendon moment arm length (ATMA) and the energy cost of running (Erun) has been disputed. Some studies suggest a short ATMA reduces Erun while others claim a long ATMA reduces Erun. For a given ankle joint moment, a short ATMA permits a higher tendon strain energy storage, whereas a long ATMA reduces muscle fascicle force and muscle energy cost but shortening velocity is increased, elevating the metabolic cost. These are all conflicting mechanisms to reduce Erun, since AT energy storage comes at a metabolic cost. Neither of these proposed mechanisms have been examined together. Methods We measured ATMA using the tendon travel method in 17 males and 3 females (24 ± 3 years, 75 ± 11 kg, 177 ± 7 cm). They ran on a motorized treadmill for 10 min at 2.5 m · s-1 while Erun was measured. AT strain energy storage, muscle lengths, velocities and muscle energy cost were calculated during time-normalized stance from force and ultrasound data. A short (SHORT n = 11, ATMA = 29.5 ± 2.0 mm) and long (LONG, n = 9, ATMA = 36.6 ± 2.5 mm) ATMA group was considered based on a bimodal distribution of measured ATMA. Results Mean Erun was 4.9 ± 0.4 J · kg-1 · m-1. The relationship between ATMA and Erun was not significant (r 2 = 0.13, p = 0.12). Maximum AT force during stance was significantly lower in LONG (5,819 ± 1,202 N) compared to SHORT (6,990 ± 920 N, p = 0.028). Neither AT stretch nor AT strain energy storage was different between groups (mean difference: 0.3 ± 1 J · step-1, p = 0.84). Fascicle force was significantly higher in SHORT (508 ± 93 N) compared to LONG (468 ± 84 N. p = 0.02). Fascicle lengths and velocities were similar between groups (p > 0.72). Muscle energy cost was significantly lower in LONG (0.028 ± 0.08 J · kg · step-1) compared to SHORT (0.045 ± 0.14 J · kg · step-1 p = 0.004). There was a significant negative relationship between ATMA and total muscle energy cost relative to body mass across the stance phase (r = -0.699, p < 0.001). Discussion Together these results suggest that a LONG ATMA serves to potentially reduce Erun by reducing the muscle energy cost of the plantarflexors during stance. The relative importance of AT energy storage and return in reducing Erun should be re-considered.
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Radovanović G, Bohm S, Peper KK, Arampatzis A, Legerlotz K. Evidence-Based High-Loading Tendon Exercise for 12 Weeks Leads to Increased Tendon Stiffness and Cross-Sectional Area in Achilles Tendinopathy: A Controlled Clinical Trial. SPORTS MEDICINE - OPEN 2022; 8:149. [PMID: 36538166 PMCID: PMC9768072 DOI: 10.1186/s40798-022-00545-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Assuming that the mechanisms inducing adaptation in healthy tendons yield similar responses in tendinopathic tendons, we hypothesized that a high-loading exercise protocol that increases tendon stiffness and cross-sectional area in male healthy Achilles tendons may also induce comparable beneficial adaptations in male tendinopathic Achilles tendons in addition to improving pain and function. OBJECTIVES We investigated the effectiveness of high-loading exercise in Achilles tendinopathy in terms of inducing mechanical (tendon stiffness, maximum strain), material (Young's modulus), morphological (tendon cross-sectional area (CSA)), maximum voluntary isometric plantar flexor strength (MVC) as well as clinical adaptations (Victorian Institute of Sports Assessment-Achilles (VISA-A) score and pain (numerical rating scale (NRS))) as the primary outcomes. As secondary outcomes, drop (DJ) and counter-movement jump (CMJ) height and intratendinous vascularity were assessed. METHODS We conducted a controlled clinical trial with a 3-month intervention phase. Eligibility criteria were assessed by researchers and medical doctors. Inclusion criteria were male sex, aged between 20 and 55 years, chronic Achilles tendinopathy confirmed by a medical doctor via ultrasound-assisted assessment, and a severity level of less than 80 points on the VISA-A score. Thirty-nine patients were assigned by sequential allocation to one of three parallel arms: a high-loading intervention (training at ~ 90% of the MVC) (n = 15), eccentric exercise (according to the Alfredson protocol) as the standard therapy (n = 15) and passive therapy (n = 14). Parameters were assessed pre- and-post-intervention. Data analysis was blinded. RESULTS Primary outcomes: Plantar flexor MVC, tendon stiffness, mean CSA and maximum tendon strain improved only in the high-loading intervention group by 7.2 ± 9.9% (p = 0.045), 20.1 ± 20.5% (p = 0.049), 8.98 ± 5.8% (p < 0.001) and -12.4 ± 10.3% (p = 0.001), respectively. Stiffness decreased in the passive therapy group (-7.7 ± 21.2%; p = 0.042). There was no change in Young's modulus in either group (p > 0.05). The VISA-A score increased in all groups on average by 19.8 ± 15.3 points (p < 0.001), while pain (NRS) dropped by -0.55 ± 0.9 points (p < 0.001). SECONDARY OUTCOMES CMJ height decreased for all groups (-0.63 ± 4.07 cm; p = 0.005). There was no change in DJ height and vascularity (p > 0.05) in either group. CONCLUSION Despite an overall clinical improvement, it was exclusively the high-loading intervention that induced significant mechanical and morphological adaptations of the plantar flexor muscle-tendon unit. This might contribute to protecting the tendon from strain-induced injury. Thus, we recommend the high-loading intervention as an effective (alternative) therapeutic protocol in Achilles tendinopathy rehabilitation management in males. CLINICAL TRIALS REGISTRATION NUMBER NCT02732782.
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Affiliation(s)
- Goran Radovanović
- grid.7468.d0000 0001 2248 7639Institute of Sports Sciences, Movement Biomechanics, Humboldt-Universität zu Berlin, Philippstr. 13, 10115 Berlin, Germany ,grid.11500.350000 0000 8919 8412Department Performance, Neuroscience, Therapy and Health, Medical School Hamburg, Faculty of Health Sciences, University of Applied Sciences and Medical University, 20457 Hamburg, Germany ,grid.11500.350000 0000 8919 8412Institute of Interdisciplinary Exercise Science and Sports Medicine, Medical School Hamburg, University of Applied Sciences and Medical University, 20457 Hamburg, Germany
| | - Sebastian Bohm
- grid.7468.d0000 0001 2248 7639Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
| | - Kim Kristin Peper
- grid.6936.a0000000123222966Munich Institute of Robotics and Machine Intelligence, Technische Universität München, 80992 Munich, Germany
| | - Adamantios Arampatzis
- grid.7468.d0000 0001 2248 7639Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, 10099 Berlin, Germany
| | - Kirsten Legerlotz
- grid.7468.d0000 0001 2248 7639Institute of Sports Sciences, Movement Biomechanics, Humboldt-Universität zu Berlin, Philippstr. 13, 10115 Berlin, Germany
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15
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Comparison between 6-week foam rolling intervention program with and without vibration on rolling and non-rolling sides. Eur J Appl Physiol 2022; 122:2061-2070. [PMID: 35704122 DOI: 10.1007/s00421-022-04975-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/24/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE The chronic effects of unilateral foam rolling (FR) or FR with vibration (VFR) intervention on the rolling and non-rolling sides (cross-education effects) are still unclear. Thus, this study aimed to investigate the effects of unilateral 6-week FR or VFR intervention on ankle dorsiflexion range of motion (DF ROM), muscle stiffness, and muscle strength in both rolling and non-rolling sides. METHODS Thirty healthy young men were randomly allocated into the FR (n = 15) or the VFR intervention group (n = 15). Participants performed three sets of unilateral FR or VFR interventions for 60 s of the calf muscles twice/week, for 6 weeks. DF ROM, gastrocnemius muscle stiffness, and maximal voluntary isometric contraction (MVIC) torque were assessed in the rolling and non-rolling sides before and after the intervention. RESULTS The DF ROM increased significantly (p < 0.05) to the same extent in the FR and VFR intervention groups on both rolling (FR: d = 0.58, VFR: d = 0.63) and non-rolling (FR: d = 0.39, VFR: d = 0.50) sides. Similarly, the passive torque at DF ROM increased significantly (p < 0.05) to the same extent in the FR and VFR intervention groups on both rolling (FR: d = 0.85, VFR: d = 0.77) and non-rolling (FR: d = 0.76, VFR: d = 0.68) sides. However, there were no significant changes in muscle stiffness and MVIC after FR and VFR interventions on both the rolling and non-rolling sides. FR and VFR interventions could increase the ROM in both the rolling and non-rolling sides but could not change muscle stiffness and strength. CONCLUSIONS The results showed that it is not necessarily needed to perform VFR to increase ROM in the long term.
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16
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Merza EY, Pearson SJ, Lichtwark GA, Malliaras P. The acute effects of higher versus lower load duration and intensity on morphological and mechanical properties of the healthy Achilles tendon: a randomized crossover trial. J Exp Biol 2022; 225:275126. [PMID: 35470387 PMCID: PMC9167578 DOI: 10.1242/jeb.243741] [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: 11/01/2021] [Accepted: 04/19/2022] [Indexed: 11/20/2022]
Abstract
The Achilles tendon (AT) exhibits volume changes related to fluid flow under acute load which may be linked to changes in stiffness. Fluid flow provides a mechanical signal for cellular activity and may be one mechanism that facilitates tendon adaptation. This study aimed to investigate whether isometric intervention involving a high level of load duration and intensity could maximize the immediate reduction in AT volume and stiffness compared with interventions involving a lower level of load duration and intensity. Sixteen healthy participants (12 males, 4 females; age 24.4±9.4 years, body mass 70.9±16.1 kg, height 1.7±0.1 m) performed three isometric interventions of varying levels of load duration (2 s and 8 s) and intensity (35% and 75% maximal voluntary isometric contraction) over a 3 week period. Freehand 3D ultrasound was used to measure free AT volume (at rest) and length (at 35%, 55% and 75% of maximum plantarflexion force) pre- and post-interventions. The slope of the force–elongation curve over these force levels represented individual stiffness (N mm−1). Large reductions in free AT volume and stiffness resulted in response to long-duration high-intensity loading whilst less reduction was produced with a lower load intensity. In contrast, no change in free AT volume and a small increase in AT stiffness occurred with lower load duration. These findings suggest that the applied load on the AT must be heavy and sustained for a long duration to maximize immediate volume reduction, which might be an acute response that enables optimal long-term tendon adaptation via mechanotransduction pathways. Summary: High levels of load duration and intensity have the greatest acute effect on the free Achilles tendon volume and stiffness.
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Affiliation(s)
- Eman Y Merza
- Department of physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston Vic 3199, Melbourne, Australia
| | - Stephen J Pearson
- Centre for Health, Sport and Rehabilitation Sciences Research, University of Salford, Greater Manchester, M5 4WT, UK
| | - Glen A Lichtwark
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St. Lucia, QLD 4072, Brisbane, Australia
| | - Peter Malliaras
- Department of physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston Vic 3199, Melbourne, Australia
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17
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Tecchio P, Zamparo P, Nardello F, Monte A. Achilles tendon mechanical properties during walking and running are underestimated when its curvature is not accounted for. J Biomech 2022; 137:111095. [PMID: 35472710 DOI: 10.1016/j.jbiomech.2022.111095] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 03/07/2022] [Accepted: 04/08/2022] [Indexed: 11/25/2022]
Abstract
Achilles tendon (AT) mechanical properties can be estimated using an inverse dynamic approach, taking into account the tendon internal moment arm (IMA) and its kinematic behavior. Although AT presents a curvilinear line of action, a straight-line function to estimate IMA and AT length is often utilized in the literature. In this study, we combined kinetic, kinematic and ultrasound data to understand the impact of two different approaches (straight-line vs. curvilinear) in determining AT mechanical properties in vivo (during walking and running at the self-selected speed). AT force and power were calculated based on data of AT IMA and AT length derived by both respective methods. All investigated parameters were significantly affected by the method utilized (paired t-test; p < 0.05): when using the curvilinear method IMA was about 5% lower and AT length about 1.2% higher, whereas peak and mean values of AT force and power were 5% higher when compared to the straight-line method (both in walking and running). Statistic-parametric mapping (SMP) analysis revealed significant differences in IMA during the early and the late stance phase of walking and during the late stance phase of running (p < 0.01); SPM revealed significant differences also in AT length during the entire stance phase in both locomotion modes (p < 0.01). These results confirm and extend previous findings to human locomotion: neglecting the AT curvature might be a source of error, resulting in underestimates not only of internal moment arm and tendon length, but also of tendon force and power.
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Affiliation(s)
- Paolo Tecchio
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy; Human Movement Science, Faculty of Sports Science, Ruhr University Bochum, Bochum, Germany.
| | - Paola Zamparo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy.
| | - Francesca Nardello
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy.
| | - Andrea Monte
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Italy.
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18
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Children who idiopathically toe-walk have greater plantarflexor effective mechanical advantage compared to typically developing children. Eur J Appl Physiol 2022; 122:1409-1417. [PMID: 35296910 PMCID: PMC9132809 DOI: 10.1007/s00421-022-04913-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 02/07/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE The effective mechanical advantage (EMA) of the plantarflexor muscles is important for gait function and is likely different from typical in equinus gait. However, this has never been quantified for children who idiopathically toe-walk (ITW), despite being routinely altered through clinical intervention. METHODS This study quantified the Achilles tendon and ground reaction force (GRF) moment arms, and the plantarflexor EMA of 5 children who ITW and 14 typically developing (TD) children, whilst walking on an instrumented treadmill. RESULTS There was no difference in the Achilles tendon moment arm length throughout stance between groups (p > 0.05). Children who ITW had a significantly greater GRF moment arm length in early stance (20-24% p = 0.001), but a significantly shorter GRF moment arm length during propulsion (68-74% of stance; p = 0.013) than TD children. Therefore, children who ITW had a greater plantarflexor EMA than TD children when active plantarflexion moments were being generated (60-70% of stance; p = 0.007). Consequently, it was estimated that children who ITW required 30% less plantarflexor muscle force for propulsion. CONCLUSION Clinical decision making should fully consider that interventions which aim to restore a typical heel-toe gait pattern risk compromising this advantageous leverage and thus, may increase the strength requirements for gait.
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19
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Kubo K. Effect of short latency stretch reflex on passive and active muscle stiffness in the soleus muscle in vivo. Eur J Appl Physiol 2022; 122:1303-1312. [DOI: 10.1007/s00421-022-04930-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 03/04/2022] [Indexed: 11/30/2022]
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20
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Kubo K, Ikebukuro T, Yata H. Mechanical properties of muscles and tendon structures in middle-aged and young men. Sci Rep 2022; 12:1702. [PMID: 35105932 PMCID: PMC8807618 DOI: 10.1038/s41598-022-05795-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 01/18/2022] [Indexed: 12/01/2022] Open
Abstract
The purpose of this study was to compare the mechanical properties of muscles and tendon structures for plantar flexor muscles at various strain rates and jump performances using single joint between middle-aged and young men in order to clarify the mechanisms of age-related decline in power output during vertical jump of middle-aged people previously reported. Passive muscle stiffness of the medial gastrocnemius muscle was determined based on passive muscle force and fascicle length during passive stretching at four angular velocities. Active muscle stiffness was calculated based on changes in muscle force and fascicle length during stretching at five angular velocities after submaximal isometric contractions. Maximal elongation and hysteresis of tendon structures were assessed from estimated muscle force—tendon elongation during ramp and ballistic contractions. Two kinds of unilateral jump heights using only ankle joint (no-countermovement and countermovement jumps) were measured. No significant differences in passive and active muscle stiffness, tendon structure properties (except for maximal elongation during ramp contraction), or jump heights were found between middle-aged and young men. The results suggest that the mechanical properties of muscles and tendon structures for plantar flexor muscles and jump performances using only ankle joint do not show age-related changes in middle-aged men.
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Affiliation(s)
- Keitaro Kubo
- Department of Life Science, The University of Tokyo, Meguro, Tokyo, Japan.
| | | | - Hideaki Yata
- Sports Science Laboratory, Wako University, Machida, Tokyo, Japan
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21
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Muscle architecture and shape changes in the gastrocnemii of active younger and older adults. J Biomech 2021; 129:110823. [PMID: 34736086 DOI: 10.1016/j.jbiomech.2021.110823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/13/2021] [Accepted: 10/13/2021] [Indexed: 11/21/2022]
Abstract
When muscles contract and change length, they also bulge in thickness and/or width. These shape changes extend the functional range of skeletal muscle by allowing individual muscle fibres to shorten at different velocities than the whole muscle. Age-related differences in muscle architecture and tissue properties influence how older muscles change shape and architecture during contractions, yet this remains unexplored in active older adults. The aim of this study was to quantify and compare in vivo muscle architecture and shape changes in the medial (MG) and lateral (LG) gastrocnemii of active younger and older adults during isometric plantarflexion contractions. Fifteen younger (21 ± 2y) and 15 older (70 ± 3y) participants performed contractions at 20%, 40%, 60%, 80%, and 100% of maximum voluntary contraction (MVC). B-mode ultrasound was used to measure fascicle length, pennation angle and muscle thickness in MG and LG. We found no influence of age on changes in normalized fascicle length and thickness, or absolute change in pennation angle during contractions. With increasing contraction level, MG and LG fascicle shortening (P < 0.001) and rotation (P < 0.001) increased. However, the change in muscle thickness increased at higher contraction levels in LG, and not MG. Similarly, increased changes in pennation angle were associated with increased muscle thickness in LG, but not MG at 80% and 100% MVC. These results suggest that (1) gastrocnemii shape changes are similar in active older and younger adults at matched levels of effort, and (2) the relationship between pennation angle and muscle thickness can differ between synergistics (LG and MG) and across contraction levels.
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22
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Pentidis N, Mersmann F, Bohm S, Schroll A, Giannakou E, Aggelousis N, Arampatzis A. Development of Muscle-Tendon Adaptation in Preadolescent Gymnasts and Untrained Peers: A 12-Month Longitudinal Study. Med Sci Sports Exerc 2021; 53:2565-2576. [PMID: 34649260 DOI: 10.1249/mss.0000000000002742] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The current study investigated the effects of long-term athletic training on the development of the triceps surae muscle-tendon unit in preadolescence. METHODS Eleven preadolescent untrained children and a group of 21 artistic gymnastics athletes of similar age (9 ± 1.7 yr) and maturity (Tanner stages I and II) participated in the study. The measurements were conducted every 3 months for 1 yr, and training volume and duration of the athletes were documented. Plantar flexor muscle strength, Achilles tendon stiffness, maximum tendon strain, and gastrocnemius medialis morphometrics were measured by integrating kinematics, ultrasonography, and dynamometry. A linear mixed-effects model was used to analyze the investigated parameters. RESULTS We found greater muscle strength (P < 0.001) in athletes compared with nonathletes but no differences in Achilles tendon stiffness (P = 0.252), indicating a training-induced imbalanced adaptation of muscle strength and tendon stiffness in preadolescent athletes. Although pennation angle (P = 0.490), thickness (P = 0.917), and fascicle length (P = 0.667) did not differ between groups, we found higher fluctuations in pennation angle and muscle strength over 1 yr in athletes. The imbalanced adaptation of muscle strength and tendon stiffness together with greater fluctuations of muscle strength resulted in greater tendon strain fluctuations over 1 yr (P = 0.017) and a higher frequency of athletes with high-level tendon strain (≥9%) compared with nonathletes. CONCLUSIONS The findings indicate an increased mechanical demand for the tendon in preadolescent athletes that could have implications for the risk of tendon overuse injury. Therefore, we recommend the implementation of individual training approaches to preserve a balanced adaptation within the triceps surae muscle-tendon unit in preadolescent athletes.
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Affiliation(s)
| | | | | | | | - Erasmia Giannakou
- Department of Physical Education and Sports Science, Democritus University of Thrace, Komotini, GREECE
| | - Nickos Aggelousis
- Department of Physical Education and Sports Science, Democritus University of Thrace, Komotini, GREECE
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Kubo K, Ikebukuro T, Yata H. Effects of plyometric training on muscle-tendon mechanical properties and behavior of fascicles during jumping. Physiol Rep 2021; 9:e15073. [PMID: 34714597 PMCID: PMC8554776 DOI: 10.14814/phy2.15073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to investigate the effects of plyometric training on the muscle-tendon mechanical properties and behavior of fascicles during jumping in order to elucidate the mechanisms of improved jump performance due to plyometric training. Eleven subjects completed a 12-week unilateral training program for plantar flexors. Active muscle stiffness with (100°·s-1 ) and without (250°·s-1 ) stretch reflex were calculated according to changes in muscle force and fascicle length during fast stretching after submaximal isometric contractions. Stiffness and hysteresis of tendon were measured using ultrasonography during ramp and ballistic contractions. Three kinds of unilateral jump heights using only ankle joint (no counter-movement jump: no-CMJ; counter-movement jump: CMJ; drop jump: DJ) on sledge apparatus were measured. During jumping, electromyographic activities (mEMG) of plantar flexors and fascicle length of the medial gastrocnemius muscle were measured. Active muscle stiffness at 250 and 100°·s-1 and maximal tendon elongation during ballistic contraction significantly increased after training. Tendon hysteresis during ballistic contraction significantly decreased after training, whereas that during ramp contraction did not. The heights of three jump tests, the ratio of mEMG during eccentric to that during concentric phases for CMJ, and the amount of fascicle shortening and shortening velocity during eccentric phase of DJ significantly increased after training. These results suggest that an increase in CMJ height was associated with changes in the muscle-tendon mechanical properties and muscle activation strategy, whereas an increase in DJ height could be explained by changes in the muscle-tendon mechanical properties, but not muscle activation strategy.
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Affiliation(s)
- Keitaro Kubo
- Department of Life ScienceThe University of TokyoMeguro, TokyoJapan
| | | | - Hideaki Yata
- Sports Science LaboratoryWako UniversityMachida, TokyoJapan
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24
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Merza E, Pearson S, Lichtwark G, Garofolini A, Malliaras P. Reliability of Human Achilles Tendon Stiffness Measures Using Freehand 3-D Ultrasound. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:973-981. [PMID: 33487471 DOI: 10.1016/j.ultrasmedbio.2021.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/09/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
Achilles tendon (AT) stiffness is an important property of both human locomotor performance and injury mechanics. Freehand 3-D ultrasound (3-DUS) is a promising method for measuring stiffness of the Achilles tendon, particularly the free AT (2-6 cm proximal to calcaneus), which is commonly injured. The aim of this study was to investigate the test-retest reliability of freehand 3-DUS in measuring free AT stiffness in humans. The free Achilles tendon length of healthy participants (n = 10) was scanned on the same day on two consecutive occasions (1 h apart) during rest and isometric plantar flexion contractions at 20%, 40% and 60% of maximum force. The slope of the force-elongation curve over these force levels represented individual stiffness (N/mm). Relative reliability was assessed using the intra-class correlation coefficient (ICC), and absolute reliability was estimated with the standard error of measurement (SEM) and smallest detectable change. Systematic bias in stiffness measures was explored by comparing test and retest distributions and Bland-Altman plots. The test-retest reliability of free AT stiffness measured using freehand 3-DUS was excellent [ICC = 0.994, 95% confidence interval [CI]: 0.978-0.999)]. The mean stiffness values at test (361.83 N/mm [170.77]) and retest (364.98 N/mm [168.57]) did not significantly differ (p = 0.72), and the smallest detectable change was 52.14 N/mm. The Bland-Altman plot indicated the absence of systematic bias (95% CI: -22.18 to 15.88). Freehand 3-DUS provides reliable and precise measures of tendon stiffness and can be used to detect small changes in free AT stiffness in response to load or tendon pathology.
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Affiliation(s)
- Eman Merza
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia
| | - Stephen Pearson
- Centre for Health, Sport and Rehabilitation Sciences Research, University of Salford, Greater Manchester, United Kingdom
| | - Glen Lichtwark
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, University of Queensland, St. Lucia, Brisbane, Australia
| | | | - Peter Malliaras
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia.
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25
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Quantifying mechanical loading and elastic strain energy of the human Achilles tendon during walking and running. Sci Rep 2021; 11:5830. [PMID: 33712639 PMCID: PMC7955091 DOI: 10.1038/s41598-021-84847-w] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/19/2021] [Indexed: 01/31/2023] Open
Abstract
The purpose of the current study was to assess in vivo Achilles tendon (AT) mechanical loading and strain energy during locomotion. We measured AT length considering its curve-path shape. Eleven participants walked at 1.4 m/s and ran at 2.5 m/s and 3.5 m/s on a treadmill. The AT length was defined as the distance between its origin at the gastrocnemius medialis myotendinous junction (MTJ) and the calcaneal insertion. The MTJ was tracked using ultrasonography and projected to the reconstructed skin surface to account for its misalignment. Skin-to-bone displacements were assessed during a passive rotation (5°/s) of the ankle joint. Force and strain energy of the AT during locomotion were calculated by fitting a quadratic function to the experimentally measured tendon force-length curve obtained from maximum voluntary isometric contractions. The maximum AT strain and force were affected by speed (p < 0.05, ranging from 4.0 to 4.9% strain and 1.989 to 2.556 kN), yet insufficient in magnitude to be considered as an effective stimulus for tendon adaptation. Besides the important tendon energy recoil during the propulsion phase (7.8 to 11.3 J), we found a recoil of elastic strain energy at the beginning of the stance phase of running (70-77 ms after touch down) between 1.7 ± 0.6 and 1.9 ± 1.1 J, which might be functionally relevant for running efficiency.
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26
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Epro G, König M, James D, Lambrianides Y, Werth J, Hunter S, Karamanidis K. Evidence that ageing does not influence the uniformity of the muscle-tendon unit adaptation in master sprinters. J Biomech 2021; 120:110364. [PMID: 33743395 DOI: 10.1016/j.jbiomech.2021.110364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 01/18/2021] [Accepted: 02/22/2021] [Indexed: 10/22/2022]
Abstract
Differences in the adaptation processes between muscle and tendon in response to mechanical loading can lead to non-uniform mechanical properties within the muscle-tendon unit (MTU), potentially increasing injury risk. The current study analysed the mechanical properties of the triceps surae (TS) MTU in 10 young (YS; 22 ± 3 yrs) and 10 older (OS; age 65 ± 8 yrs; i.e. master) (inter)national level sprinters and 11 young recreationally active adults (YC; 23 ± 3 yrs) to detect possible non-uniformities in muscle and tendon adaptation due to habitual mechanical loading and ageing. Triceps surae muscle strength, tendon stiffness and maximal tendon strain were assessed in both legs during maximal voluntary isometric plantarflexion contractions via dynamometry and ultrasonography. Irrespective of the leg, OS and YC in comparison to YS demonstrated significantly (P < 0.05) lower TS muscle strength and tendon stiffness, with no differences between OS and YC. Furthermore, no group differences were detected in the maximal tendon strain (average of both legs: OS 3.7 ± 0.8%, YC 4.4 ± 0.8% and YS 4.3 ± 0.9%) as well as in the inter-limb symmetry indexes in muscle strength, tendon stiffness and maximal tendon strain (range across groups: -5.8 to 4.9%; negative value reflects higher value for the non-preferred leg). Thus, the findings provide no clear evidence for a disruption in the TS MTU uniformity in master sprinters, demonstrating that ageing tendons can maintain their integrity to meet the increased functional demand due to elite sports.
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Affiliation(s)
- G Epro
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom.
| | - M König
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
| | - D James
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
| | - Y Lambrianides
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
| | - J Werth
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
| | - S Hunter
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
| | - K Karamanidis
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, United Kingdom
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27
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Kovács B, Kóbor I, Sebestyén Ö, Tihanyi J. Longer Achilles tendon moment arm results in better running economy. Physiol Int 2021; 107:527-541. [PMID: 33410770 DOI: 10.1556/2060.2020.10000] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 08/29/2020] [Indexed: 11/19/2022]
Abstract
Based on the current literature, the link between Achilles tendon moment arm length and running economy is not well understood. Therefore, the aim of this study was to further investigate the connection between Achilles tendon moment arm and running economy and the influence of Achilles tendon moment arm on the function of the plantarflexor muscle-tendon unit during running.Ten male competitive marathon runners volunteered for this study. The participants ran on a treadmill at two running speeds: 3 and 3.5 m s-1. During running the oxygen consumption, lower leg kinematics, electrical activity of plantar flexor muscles, and fascicle behavior of the lateral gastrocnemius were measured simultaneously. On the second occasion, an MRI scan of the right leg was taken and used to estimate the Achilles tendon moment arm length.There was a negative correlation between running economy and the body height normalized moment arm length at both selected speeds (r = -0.68, P = 0.014 and r = -0.70, P = 0.01). In addition, Achilles tendon moment arm length correlated with the amplitude of the ankle flexion at both speeds (r = -0.59, P = 0.03 and r = -0.60, P = 0.03) and with the electrical activity of the medial gastrocnemius muscle at 3 m s-1 speed (r = -0.62, P = 0.02). Our finding supports the concept that a longer moment arm could be beneficial for distance runners.
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Affiliation(s)
- B Kovács
- 1Department of Kinesiology, University of Physical Education, Budapest, Hungary
| | - I Kóbor
- 2Semmelweis University, MR Research Centre, Budapest, Hungary
| | - Ö Sebestyén
- 1Department of Kinesiology, University of Physical Education, Budapest, Hungary
| | - J Tihanyi
- 1Department of Kinesiology, University of Physical Education, Budapest, Hungary
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28
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Buffey AJ, Onambélé-Pearson GL, Erskine RM, Tomlinson DJ. The validity and reliability of the Achilles tendon moment arm assessed with dual-energy X-ray absorptiometry, relative to MRI and ultrasound assessments. J Biomech 2020; 116:110204. [PMID: 33429074 DOI: 10.1016/j.jbiomech.2020.110204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/04/2020] [Accepted: 12/11/2020] [Indexed: 01/10/2023]
Abstract
Dual-energy X-ray absorptiometry (DXA) in single energy mode has been shown to permit the visualisation of bone and soft tissue, such as the patellar tendon through two-dimensional sagittal imaging. However, there is no validated DXA-based measurement of the Achilles tendon moment arm (dAT). The aims of this study were: 1) to compare in vivo DXA derived measurements of the dAT at rest against two previously validated methods: tendon excursion (TE) and magnetic resonance imaging (MRI) at three ankle angles (-5°, 0° and +10°). 2) analyse the intra-day reliability of the DXA method at all ankle angles and compare between methods. Twelve healthy adults (mean ± SD: 31.4 ± 9.5 years; 174.0 ± 9.5 cm; 76.2 ± 16.6 kg) participated in this study, involving test-retest DXA scans, ultrasound scans and one MRI scan. The dAT was defined as the distance from the centre of the calcaneal-tibial joint axis to the Achilles tendon (AT) muscle-tendon line of action. DXA derived dAT measures were significantly greater than MRI measurements (19.7-24.9%) and were 45.2% significantly larger than the TE method. The test-retest reliability of the DXA technique at 0° was high [CV = 1.38%; ICC = 0.96] and despite the consistently larger dAT lengths obtained using DXA, MRI and DEXA data were strongly correlated (r = 0.878, p < 0.001). In conclusion, the DXA technique allowed for highly reproducible in vivo dAT measurement at rest, which has implications for the calculation of AT forces in vivo and the ability to predict the measurement from one tool to the other, thereby providing a novel basis to contrast existing and future studies.
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Affiliation(s)
- Aidan J Buffey
- Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester, UK; Department of Physical Education and Sport Sciences; University of Limerick, Limerick, Ireland; Health Research Institute, University of Limerick, Limerick, Ireland
| | - Gladys L Onambélé-Pearson
- Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester, UK
| | - Robert M Erskine
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK; Institute of Sport, Exercise & Health, University College London, London, UK
| | - David J Tomlinson
- Musculoskeletal Science and Sports Medicine Research Centre, Manchester Metropolitan University, Manchester, UK.
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29
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Karamanidis K, Epro G. Monitoring Muscle-Tendon Adaptation Over Several Years of Athletic Training and Competition in Elite Track and Field Jumpers. Front Physiol 2020; 11:607544. [PMID: 33391022 PMCID: PMC7772406 DOI: 10.3389/fphys.2020.607544] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/27/2020] [Indexed: 12/20/2022] Open
Abstract
Differences in muscle and tendon responsiveness to mechanical stimuli and time courses of adaptive changes may disrupt the interaction of the musculotendinous unit (MTU), increasing the risk for overuse injuries. We monitored training-induced alterations in muscle and tendon biomechanical properties in elite jumpers over 4 years of athletic training to detect potential non-synchronized adaptations within the triceps surae MTU. A combined cross-sectional and longitudinal investigation over 4 years was conducted by analyzing triceps surae MTU mechanical properties in both legs via dynamometry and ultrasonography in 67 elite track and field jumpers and 24 age-matched controls. Fluctuations in muscle and tendon adaptive changes over time were quantified by calculating individual residuals. The cosine similarity of the relative changes of muscle strength and tendon stiffness between sessions served as a measure of uniformity of adaptive changes. Our cross-sectional study was unable to detect clear non-concurrent differences in muscle strength and tendon stiffness in elite jumpers. However, when considering the longitudinal data over several years of training most of the jumpers demonstrated greater fluctuations in muscle strength and tendon stiffness and hence tendon strain compared to controls, irrespective of training period (preparation vs. competition). Moreover, two monitored athletes with chronic Achilles tendinopathy showed in their affected limb lower uniformity in MTU adaptation as well as higher fluctuations in tendon strain over time. Habitual mechanical loading can affect the MTU uniformity in elite jumpers, leading to increased mechanical demand on the tendon over an athletic season and potentially increased risk for overuse injuries.
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Affiliation(s)
- Kiros Karamanidis
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Gaspar Epro
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
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30
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Holzer D, Paternoster FK, Hahn D, Siebert T, Seiberl W. Considerations on the human Achilles tendon moment arm for in vivo triceps surae muscle-tendon unit force estimates. Sci Rep 2020; 10:19559. [PMID: 33177655 PMCID: PMC7658232 DOI: 10.1038/s41598-020-76625-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/29/2020] [Indexed: 01/28/2023] Open
Abstract
Moment arm-angle functions (MA-a-functions) are commonly used to estimate in vivo muscle forces in humans. However, different MA-a-functions might not only influence the magnitude of the estimated muscle forces but also change the shape of the muscle’s estimated force-angle relationship (F-a-r). Therefore, we investigated the influence of different literature based Achilles tendon MA-a-functions on the triceps surae muscle–tendon unit F-a-r. The individual in vivo triceps torque–angle relationship was determined in 14 participants performing maximum voluntary fixed-end plantarflexion contractions from 18.3° ± 3.2° plantarflexion to 24.2° ± 5.1° dorsiflexion on a dynamometer. The resulting F-a-r were calculated using 15 literature-based in vivo Achilles tendon MA-a-functions. MA-a-functions affected the F-a-r shape and magnitude of estimated peak active triceps muscle–tendon unit force. Depending on the MA-a-function used, the triceps was solely operating on the ascending limb (n = 2), on the ascending limb and plateau region (n = 12), or on the ascending limb, plateau region and descending limb of the F-a-r (n = 1). According to our findings, the estimated triceps muscle–tendon unit forces and the shape of the F-a-r are highly dependent on the MA-a-function used. As these functions are affected by many variables, we recommend using individual Achilles tendon MA-a-functions, ideally accounting for contraction intensity-related changes in moment arm magnitude.
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Affiliation(s)
- Denis Holzer
- Department of Sport and Health Sciences, Biomechanics in Sports, Technical University of Munich, Munich, Germany.
| | - Florian Kurt Paternoster
- Department of Sport and Health Sciences, Biomechanics in Sports, Technical University of Munich, Munich, Germany
| | - Daniel Hahn
- Human Movement Science, Ruhr University Bochum, Faculty of Sport Science, Bochum, Germany.,School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
| | - Tobias Siebert
- Department of Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
| | - Wolfgang Seiberl
- Department of Sport and Health Sciences, Biomechanics in Sports, Technical University of Munich, Munich, Germany. .,Department of Human Sciences, Human Movement Science, Bundeswehr University Munich, Neubiberg, Germany.
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31
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Kubo K, Miyazaki D, Yata H, Tsunoda N. Mechanical properties of muscle and tendon at high strain rate in sprinters. Physiol Rep 2020; 8:e14583. [PMID: 33038067 PMCID: PMC7547534 DOI: 10.14814/phy2.14583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/03/2022] Open
Abstract
The aim of the present study was to compare the mechanical properties of muscles and tendons at high strain rates between sprinters and untrained men. Fifteen sprinters and 18 untrained men participated in this study. Active muscle stiffness of the medial gastrocnemius muscle was calculated according to changes in the estimated muscle force and fascicle length during fast stretching at five different angular velocities (100, 200, 300, 500, and 600 deg·s-1 ) after submaximal isometric contractions. Stiffness and hysteresis of tendon structures were measured during ramp and ballistic contractions. Active muscle stiffness at 500 deg·s-1 (p = .070) and 600 deg·s-1 (p = .041) was greater in sprinters than untrained men, whereas no differences in those at 100, 200, and 300 deg·s-1 were found between the two groups. There were no differences in stiffness or hysteresis of tendon structures measured during ramp and ballistic contractions between the two groups. These results suggest that, for sprinters, greater active muscle stiffness at a high angular velocity is caused by exercising with a high angular velocity that is typical of their training.
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Affiliation(s)
- Keitaro Kubo
- Department of Life ScienceThe University of TokyoMeguroJapan
| | | | - Hideaki Yata
- Sports Science LaboratoryWako UniversityMachidaJapan
| | - Naoya Tsunoda
- Faculty of Physical EducationKokushikan UniversityTokyoJapan
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32
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Iqbal K. Optimal time-varying postural control in a single-link neuromechanical model with feedback latencies. BIOLOGICAL CYBERNETICS 2020; 114:485-497. [PMID: 32865604 DOI: 10.1007/s00422-020-00843-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
Maintaining balance during quiet standing is a challenging task for the neural control mechanisms due to the inherent instabilities involved in the task. The feedback latencies and the lowpass characteristics of skeletal muscle add to the difficulty of regulating postural dynamics in real-time. Inverted-pendulum (IP) type robotic models have served as a popular paradigm to investigate control of postural balance. In this study, an in-depth neuromechanical postural control model is developed from physiological principles. The model comprises a single-segment IP robotic model, Hill-type muscle model, and proprioceptive feedback from the muscle spindle (MS) and golgi tendon organ (GTO). An optimal proportional-integral-derivative (PID) controller is proposed to realize effective postural control amid latencies in sensory feedback. The neural commands for postural stabilization are generated by a time-varying PID controller, tuned using linear quadratic regulator (LQR) principles. Computer simulations are used to assess the efficacy of the tuned PID-LQR controller. Sensitivity analysis of the controlled system shows a delay tolerance of 300ms. Preliminary empirical data in support of the mathematical model were obtained from perturbation experiments. The model response to perturbation torque, measured in terms of the center of mass (COM) excursion in the anterior-posterior (AP) direction, displays a high degree of correlation with the empirical data ([Formula: see text]).
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Affiliation(s)
- Kamran Iqbal
- University of Arkansas Little Rock, Little Rock, AR, 72204, USA.
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33
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Kubo K, Ikebukuro T. Changes in joint, muscle, and tendon stiffness following repeated hopping exercise. Physiol Rep 2020; 7:e14237. [PMID: 31605467 PMCID: PMC6789417 DOI: 10.14814/phy2.14237] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 08/22/2019] [Accepted: 08/26/2019] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to elucidate the mechanisms of decline in joint stiffness after repeated stretch‐shortening cycle exercises according to changes in both muscle‐tendon properties and neuromuscular activities. Eleven males performed fatigue task (5 sets of 50 hopping). Ankle joint stiffness and electromyographic activities (mEMG) of plantar flexor and tibial anterior muscles during drop jump were measured before and after fatigue task. Active muscle stiffness with (100 deg·sec−1) and without (250 deg·sec−1) stretch reflex were calculated according to changes in estimated muscle force and fascicle length during fast stretching after submaximal isometric contractions. Tendon stiffness was measured during ramp and ballistic contractions. After fatigue task, joint stiffness significantly decreased by 20.7 %, whereas mEMG of measured muscles during drop jump did not. After fatigue task, active muscle stiffness with and without stretch reflex significantly decreased by 15.7 % and 21.5 %, and tendon stiffness measured during ramp and ballistic contractions did not change. In addition, the relative change in joint stiffness was significantly correlated with that in active muscle stiffness with stretch reflex (r = 0.737, P = 0.009), but not with those in the other measured variables. These results suggested that the decline in joint stiffness after repeated hopping exercises would be caused by changes in active muscle stiffness, but not those in tendon properties or neuromuscular activities.
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Affiliation(s)
- Keitaro Kubo
- Department of Life Science, The University of Tokyo, Meguro, Tokyo, Japan
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34
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Miller RH, Krupenevich RL. Medial knee cartilage is unlikely to withstand a lifetime of running without positive adaptation: a theoretical biomechanical model of failure phenomena. PeerJ 2020; 8:e9676. [PMID: 32844066 PMCID: PMC7414768 DOI: 10.7717/peerj.9676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 07/16/2020] [Indexed: 01/24/2023] Open
Abstract
Runners on average do not have a high risk of developing knee osteoarthritis, even though running places very high loads on the knee joint. Here we used gait analysis, musculoskeletal modeling, and a discrete-element model of knee contact mechanics to estimate strains of the medial knee cartilage in walking and running in 22 young adults (age 23 ± 3 years). A phenomenological model of cartilage damage, repair, and adaptation in response to these strains then estimated the failure probability of the medial knee cartilage over an adult lifespan (age 23-83 years) for 6 km/day of walking vs. walking and running 3 km/day each. With no running, by age 55 the cumulative probability of medial knee cartilage failure averaged 36% without repair and 13% with repair, similar to reports on incidence of knee osteoarthritis in non-obese adults with no knee injuries, but the probability for running was very high without repair or adaptation (98%) and remained high after including repair (95%). Adaptation of the cartilage compressive modulus, cartilage thickness, and the tibiofemoral bone congruence in response to running (+1.15 standard deviations of their baseline values) was necessary for the failure probability of walking and running 3 km/day each to equal the failure probability of walking 6 km/day. The model results suggest two conclusions for further testing: (i) unlike previous findings on the load per unit distance, damage per unit distance on the medial knee cartilage is greater in running vs. walking, refuting the "cumulative load" hypothesis for long-term joint health; (ii) medial knee cartilage is unlikely to withstand a lifetime of mechanical loading from running without a natural adaptation process, supporting the "cartilage conditioning" hypothesis for long-term joint health.
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Affiliation(s)
- Ross H Miller
- Department of Kinesiology, University of Maryland, College Park, MD, United States of America.,Neuroscience & Cognitive Science Program, University of Maryland, College Park, MD, United States of America
| | - Rebecca L Krupenevich
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, United States of America
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Nuckols RW, Dick TJM, Beck ON, Sawicki GS. Ultrasound imaging links soleus muscle neuromechanics and energetics during human walking with elastic ankle exoskeletons. Sci Rep 2020; 10:3604. [PMID: 32109239 PMCID: PMC7046782 DOI: 10.1038/s41598-020-60360-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 02/07/2020] [Indexed: 11/16/2022] Open
Abstract
Unpowered exoskeletons with springs in parallel to human plantar flexor muscle-tendons can reduce the metabolic cost of walking. We used ultrasound imaging to look 'under the skin' and measure how exoskeleton stiffness alters soleus muscle contractile dynamics and shapes the user's metabolic rate during walking. Eleven participants (4F, 7M; age: 27.7 ± 3.3 years) walked on a treadmill at 1.25 m s-1 and 0% grade with elastic ankle exoskeletons (rotational stiffness: 0-250 Nm rad-1) in one training and two testing days. Metabolic savings were maximized (4.2%) at a stiffness of 50 Nm rad-1. As exoskeleton stiffness increased, the soleus muscle operated at longer lengths and improved economy (force/activation) during early stance, but this benefit was offset by faster shortening velocity and poorer economy in late stance. Changes in soleus activation rate correlated with changes in users' metabolic rate (p = 0.038, R2 = 0.44), highlighting a crucial link between muscle neuromechanics and exoskeleton performance; perhaps informing future 'muscle-in-the loop' exoskeleton controllers designed to steer contractile dynamics toward more economical force production.
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Affiliation(s)
- R W Nuckols
- Joint Department of Biomedical Engineering, UNC Chapel Hill and NC State University, Raleigh, NC, 27607, USA.
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02138, USA.
| | - T J M Dick
- Joint Department of Biomedical Engineering, UNC Chapel Hill and NC State University, Raleigh, NC, 27607, USA
- School of Biomedical Sciences, University of Queensland, St Lucia, Queensland, Australia
| | - O N Beck
- George W. Woodruff School of Mechanical Engineering and School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - G S Sawicki
- Joint Department of Biomedical Engineering, UNC Chapel Hill and NC State University, Raleigh, NC, 27607, USA.
- George W. Woodruff School of Mechanical Engineering and School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
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Schumacher C, Sharbafi M, Seyfarth A, Rode C. Biarticular muscles in light of template models, experiments and robotics: a review. J R Soc Interface 2020; 17:20180413. [PMID: 32093540 PMCID: PMC7061696 DOI: 10.1098/rsif.2018.0413] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/31/2020] [Indexed: 11/25/2022] Open
Abstract
Leg morphology is an important outcome of evolution. A remarkable morphological leg feature is the existence of biarticular muscles that span adjacent joints. Diverse studies from different fields of research suggest a less coherent understanding of the muscles' functionality in cyclic, sagittal plane locomotion. We structured this review of biarticular muscle function by reflecting biomechanical template models, human experiments and robotic system designs. Within these approaches, we surveyed the contribution of biarticular muscles to the locomotor subfunctions (stance, balance and swing). While mono- and biarticular muscles do not show physiological differences, the reviewed studies provide evidence for complementary and locomotor subfunction-specific contributions of mono- and biarticular muscles. In stance, biarticular muscles coordinate joint movements, improve economy (e.g. by transferring energy) and secure the zig-zag configuration of the leg against joint overextension. These commonly known functions are extended by an explicit role of biarticular muscles in controlling the angular momentum for balance and swing. Human-like leg arrangement and intrinsic (compliant) properties of biarticular structures improve the controllability and energy efficiency of legged robots and assistive devices. Future interdisciplinary research on biarticular muscles should address their role for sensing and control as well as non-cyclic and/or non-sagittal motions, and non-static moment arms.
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Affiliation(s)
- C. Schumacher
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Institute of Sport Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - M. Sharbafi
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Institute of Sport Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - A. Seyfarth
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Institute of Sport Science, Technische Universität Darmstadt, Darmstadt, Germany
| | - C. Rode
- Motion and Exercise Science, University of Stuttgart, Stuttgart, Germany
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Koryak YA. Changes in human skeletal muscle architecture and function induced by extended spaceflight. J Biomech 2019; 97:109408. [PMID: 31662199 DOI: 10.1016/j.jbiomech.2019.109408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/20/2019] [Accepted: 10/06/2019] [Indexed: 11/15/2022]
Abstract
The aim of this study was to quantitatively describe the relationships between joint angles and muscle architecture (lengths (Lf) and angles (Θf) of fascicles) of human triceps surae [medial (MG) and lateral (LG) gastrocnemius and soleus (SOL) muscles] invivo for three men-cosmonaut after long-duration spaceflight. Sagittal sonographs of MG, LG, SOL were taken at ankle was positioned at 15° (dorsiflexion), 0° (neutral position), +15°, and +30° (plantarflexion), with the knee at 90° at rest and after a long-duration spaceflight. At each position, longitudinal ultrasonic images of the MG and LG and SOL were obtained while the cosmonauts was relaxed from which fascicle lengths and angles with respect to the aponeuroses were determined. After space flight plantarflexor force declined significantly (26%; p < 0.001). The internal architecture of the GM, and LG, and SOL muscle was significantly altered. In the passive condition, Lf changed from 45, 53, and 39 mm (knee, 0°, ankle, -15°) to 26, 33, and 28 mm (knee, 90° ankle, 30°) for MG, LG, and SOL, respectively. Different lengths and angles of fascicles, and their changes by contraction, might be related to differences in force-producing capabilities of the muscles and elastic characteristics of tendons and aponeuroses. The three heads of the triceps surae muscle substantially differ in architecture, which probably reflects their functional roles. Differences in fiber length and pennation angle that were observed among the muscles and could be associated with differences in force production and in elastic properties of musculo-tendinous complex and aponeuroses.
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Affiliation(s)
- Yuri A Koryak
- State Scientific Center of the Russian Federation - Institute of Biomedical Problems of the Russian Academy of Sciences, Russia.
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Trezise J, Blazevich AJ. Anatomical and Neuromuscular Determinants of Strength Change in Previously Untrained Men Following Heavy Strength Training. Front Physiol 2019; 10:1001. [PMID: 31447693 PMCID: PMC6691166 DOI: 10.3389/fphys.2019.01001] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 07/18/2019] [Indexed: 11/13/2022] Open
Abstract
This study examined whether changes in strength following a moderate-duration strength training program were associated with changes in specific combinations of anatomical and neuromuscular variables. 36 men (18-40 y) completed 10 weeks of lower-limb heavy resistance (6-RM) strength training. Measurements included cross-sectional area (CSA), fascicle length (lf) and fascicle angle (θf) from proximal, middle and distal regions of the four quadriceps components; agonist (EMG:M), antagonist (EMG) muscle activities and percent voluntary quadriceps activation (%VA; interpolated twitch technique); patellar tendon moment arm distance; and maximal isometric, concentric and eccentric (60° s-1) torque. Multiple regression models were developed to quantify the relationship between the change in maximum torque and the changes in combinations of anatomical and neuromuscular variables. The best model for each contraction mode was determined using Akaike's Information Criterion (AICc), an information-theoretic approach for model selection. Strength increased significantly following training (mean range = 12.5-17.2%), and moderate relationships were observed between modeled data (using best-fit prediction models) and the change in torque for each contraction mode. The change in isometric torque was best (although weakly) predicted by the linear combination of the change in proximal-region vastus lateralis (VL) CSA and fascicle angle (R 2 = 0.27, p < 0.05; AICc wi = 0.52, i.e., the probability the model would be selected as the "best model"). The models best predicting the change in concentric and eccentric torque both included the combination of the change in quadriceps (i.e., mean of all muscles) EMG:M and the change in vastus intermedius fascicle angle combined with either a change in proximal-region VL (R 2 = 0.40, p < 0.001; AICc wi = 0.15) or whole quadriceps (R 2 = 0.41, p < 0.001; AICc wi = 0.30) CSA (concentric and eccentric, respectively). Models incorporating the change in proximal CSA typically received substantial support (AICC < 2) for concentric torque prediction models, and the change in % VA and pre-training moment arm distance had substantial support for use in eccentric torque prediction models. In conclusion, adaptations varied between individuals, however strength training programs targeted to improve a group of variables that particularly includes agonist muscle activation might yield the greatest improvements in concentric and eccentric knee extension strength, whereas proximal muscle size and fascicle angle appear most important for isometric torque improvements.
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Affiliation(s)
- J Trezise
- School of Medical and Health Sciences, Centre for Exercise and Sports Science Research (CESSR), Edith Cowan University, Joondalup, WA, Australia
| | - A J Blazevich
- School of Medical and Health Sciences, Centre for Exercise and Sports Science Research (CESSR), Edith Cowan University, Joondalup, WA, Australia
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Letter to the editor regarding: Effects of cerebral palsy on Achilles tendon moment arm length - Do children with CP have larger or smaller moment arms than typically developing children? Commentary on: Alexander et al. J Biomech 2019; 92:175-177. [PMID: 31164223 DOI: 10.1016/j.jbiomech.2019.03.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/03/2019] [Indexed: 11/23/2022]
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Wade FE, Lewis GS, Piazza SJ. Estimates of Achilles tendon moment arm differ when axis of ankle rotation is derived from ankle motion. J Biomech 2019; 90:71-77. [DOI: 10.1016/j.jbiomech.2019.04.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/03/2019] [Accepted: 04/22/2019] [Indexed: 10/26/2022]
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Epro G, Hunter S, König M, Schade F, Karamanidis K. Evidence of a Uniform Muscle-Tendon Unit Adaptation in Healthy Elite Track and Field Jumpers: A Cross Sectional Investigation. Front Physiol 2019; 10:574. [PMID: 31156457 PMCID: PMC6529647 DOI: 10.3389/fphys.2019.00574] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 04/24/2019] [Indexed: 01/01/2023] Open
Abstract
Different adaptive responses to mechanical loading between muscle and tendon can lead to non-uniform biomechanical properties within the muscle-tendon unit. The current study aimed to analyze the mechanical properties of the triceps surae muscle-tendon unit in healthy male and female elite track and field jumpers in order to detect possible inter-limb differences and intra-limb non-uniformities in muscle and tendon adaptation. The triceps surae muscle strength and tendon stiffness were analyzed in both limbs during maximal voluntary isometric plantar flexion contractions using synchronous dynamometry and ultrasonography in sixty-seven healthy young male (n = 35) and female (n = 32) elite international level track and field jumpers (high jump, long jump, triple jump, pole vault). Triceps surae muscle-tendon unit intra-limb uniformity was assessed using between limb symmetry indexes in the muscle strength and tendon stiffness. Independent from sex and jumping discipline the take-off leg showed a significantly higher (p < 0.05) triceps surae muscle strength and tendon stiffness, suggesting different habitual mechanical loading between legs. However, despite these inter-limb discrepancies no differences were detected in the symmetry indexes of muscle strength (5.9 ± 9.4%) and tendon stiffness (8.1 ± 11.5%). This was accompanied by a significant correlation between the symmetry indexes of muscle strength and tendon stiffness (r = 0.44; p < 0.01; n = 67). Thus, the current findings give evidence for a uniform muscle-tendon unit adaptation in healthy elite track and field jumpers, which can be reflected as a protective mechanism to maintain its integrity to meet the functional demand.
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Affiliation(s)
- Gaspar Epro
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Steve Hunter
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Matthias König
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
| | - Falk Schade
- Olympic Training Center Rheinland, Cologne, Germany
| | - Kiros Karamanidis
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, London, United Kingdom
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Deforth M, Zwicky L, Horn T, Hintermann B. The effect of foot type on the Achilles tendon moment arm and biomechanics. Foot (Edinb) 2019; 38:91-94. [PMID: 30849670 DOI: 10.1016/j.foot.2018.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/30/2018] [Accepted: 10/08/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND The aim was to calculate the Achilles tendon moment arm in different degrees of plantarflexion for pes planus, pes cavus and normal arched feet. METHODS 99 patients (99 radiographs; 40 males, 59 females; mean age 49 years, SD 15) with a healthy ankle joint and a preoperative weightbearing lateral radiograph of the foot were included. Three groups (pes planus, pes cavus and normal-arched feet) with equal sample sizes (n=33) were formed. On radiographs, the angle formed between a horizontal line and the line connecting the insertion of the Achilles tendon with the center of rotation of the ankle, was measured. The interrater reliabilities (ICC) of the angle alpha were compared on radiographs and on MRIs. Using the angle alpha, the Achilles tendon moment arm was calculated in different plantarflexion positions. RESULTS The ICC of alpha was higher on radiographs (0.84, [0.73-0.91]) than on MRIs (0.61, [0.27-0.81]). The average alpha was statistically significantly different (normal arched foot 31 degrees (°), pes planus 24°, pes cavus 36°, p=0.021), resulting in a significant shorter Achilles tendon moment arm for pes cavus than for pes planus (p<0.0001) and normal arched feet (p=0.006) in neutral position. CONCLUSION The data suggests that it is feasible to use radiographs to measure the Achilles tendon moment arm. The maximum Achilles tendon moment arm is reached at different angles of ankle flexion for pes cavus, pes planus and normal-arched feet. This has to be taken into consideration when planning surgeries.
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Affiliation(s)
- Manja Deforth
- Clinic for Orthopaedic and Trauma Surgery, Kantonsspital Baselland, Switzerland
| | - Lukas Zwicky
- Clinic for Orthopaedic and Trauma Surgery, Kantonsspital Baselland, Switzerland
| | - Tamara Horn
- Clinic for Orthopaedic and Trauma Surgery, Kantonsspital Baselland, Switzerland
| | - Beat Hintermann
- Clinic for Orthopaedic and Trauma Surgery, Kantonsspital Baselland, Switzerland.
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Baxter JR, Farber DC, Hast MW. Plantarflexor fiber and tendon slack length are strong determinates of simulated single-leg heel raise height. J Biomech 2019; 86:27-33. [PMID: 30722935 DOI: 10.1016/j.jbiomech.2019.01.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/15/2019] [Accepted: 01/17/2019] [Indexed: 10/27/2022]
Abstract
Achilles tendon ruptures have been linked with detrimental changes in muscle-tendon structure, which may help explain long-term functional deficits. However, the causal effects of muscle-tendon structure on joint function have not been tested in a controlled setting. Therefore, the purpose of this study was to test the implications of muscle-tendon unit parameters on simulated single-leg heel raise height. We hypothesized that muscle fiber length and resting ankle angle - a clinical surrogate measure of tendon slack length - would predict single-leg heel raise height more strongly than other parameters. To test this hypothesis, we developed a two-part simulation paradigm that recreated clinically relevant muscle-tendon scenarios and then tested these parameters on single-leg heel raise height. We found that longer muscle fibers had the greatest positive effect on single-leg heel raise height. However, tendon slack length, determined by simulating resting ankle angles in a secondary analysis, revealed a stronger negative correlation with heel raise height. Our findings support previous clinical observations that both muscle fascicle length and resting tendon length are important muscle-tendon parameters for patient function. In addition to minimizing tendon elongation following rupture, treatment plans should focus on preserving plantarflexor muscle structure to mitigate functional loses following Achilles tendon ruptures.
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Affiliation(s)
- Josh R Baxter
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA.
| | - Daniel C Farber
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael W Hast
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA, USA
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de Brito Fontana H, de Campos D, Sawatsky A, Han SW, Herzog W. Why do muscles lose torque potential when activated within their agonistic group? J Exp Biol 2019; 223:jeb.213843. [DOI: 10.1242/jeb.213843] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/26/2019] [Indexed: 11/20/2022]
Abstract
Agonistic muscles lose approximately 20% of their individual torque generating capacity when activated with their agonistic muscles compared to when stimulated in isolation. In this study, we (i) tested if this loss in torque was accompanied by a corresponding loss in force, thereby testing the potential role of changes in moment arms between conditions; (ii) removed all inter-muscular connections between the quadriceps muscles, thus determining the potential role of inter-muscular force transmission; and (iii) systematically changed the inter-muscular pressure by performing experiments at different activation/force levels, thereby exploring the possible role of inter-muscular pressure in the loss of torque capacity with simultaneous muscle activation. Experiments were performed in a New Zealand White rabbit quadriceps model (n=5). Torque and force were measured during activation of femoral nerve branches that supply the individual quadriceps muscles while activating these branches simultaneously and in isolation. Regardless of joint angle and inter-muscular connections between muscles, the differences in torque values between the simultaneous and the isolated activation of the quadriceps muscles were also observed for the directly measured force values. Mean differences in simultaneous and isolated muscle activation remained similar between the intact and separated conditions: torque difference (21±5% of maximum isometric torque of intact condition [MICtorque], versus 19±6% MICtorque respectively) and for force (18±3% MICforce versus 19±7% MICforce respectively). The absolute torque loss was independent of the force, and thus presumably the inter-muscular pressures. Based on these results, we conclude that neither moment arm, inter-muscular pressure nor inter-muscular force transmission seems to be the primary cause for the torque deficit observed during simultaneous compared to isolated muscle activation. The mechanisms underlying loss of force capacity during agonistic muscle contraction remain unknown.
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Affiliation(s)
- Heiliane de Brito Fontana
- Department of Morphological Sciences, School of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Daiani de Campos
- Biomechanics Laboratory, School of Sport Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Andrew Sawatsky
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Seong-won Han
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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Children with cerebral palsy have larger Achilles tendon moment arms than typically developing children. J Biomech 2019; 82:307-312. [DOI: 10.1016/j.jbiomech.2018.11.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/14/2018] [Accepted: 11/02/2018] [Indexed: 01/19/2023]
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Ogaya S, Kubota R, Chujo Y, Hirooka E, Ito K, Kwang-ho K, Hase K. Potential of muscles to accelerate the body during late-stance forward progression in individuals with knee osteoarthritis. Hum Mov Sci 2018; 61:109-116. [DOI: 10.1016/j.humov.2018.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 07/03/2018] [Accepted: 07/24/2018] [Indexed: 11/15/2022]
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König M, Hemmers S, Epro G, McCrum C, Ackermans TMA, Hartmann U, Karamanidis K. Matching Participants for Triceps Surae Muscle Strength and Tendon Stiffness Does Not Eliminate Age-Related Differences in Mechanical Power Output During Jumping. Front Physiol 2018; 9:1345. [PMID: 30356888 PMCID: PMC6190886 DOI: 10.3389/fphys.2018.01345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 09/06/2018] [Indexed: 11/17/2022] Open
Abstract
Reductions in muscular power output and performance during multi-joint motor tasks with aging have often been associated with muscle weakness. This study aimed to examine if matching younger and middle-aged adults for triceps surae (TS) muscle strength and tendon stiffness eliminates age-related differences in muscular power production during drop jump. The maximal ankle plantar flexion moment and gastrocnemius medialis tendon stiffness of 29 middle-aged (40-67 years) and 26 younger (18-30 years) healthy physically active male adults were assessed during isometric voluntary ankle plantar flexion contractions using simultaneous dynamometry and ultrasonography. The elongation of the tendon during the loading phase was assessed by digitizing the myotendinous junction of the gastrocnemius medialis muscle. Eight younger (23 ± 3 years) and eight middle-aged (54 ± 7 years) adults from the larger subject pool were matched for TS muscle strength and tendon stiffness (plantar flexion moment young: 3.1 ± 0.4 Nm/kg; middle-aged: 3.2 ± 0.5 Nm/kg; tendon stiffness: 553 ± 97 vs. 572 ± 100 N/mm) and then performed series of drop jumps from different box heights (13, 23, 33, and 39 cm) onto a force plate (sampling frequency 1000 Hz). The matched young and middle-aged adults showed similar drop jump heights for all conditions (from lowest to highest box height: 18.0 ± 3.7 vs. 19.7 ± 4.8 cm; 22.6 ± 4.2 vs. 22.9 ± 4.9 cm; 24.8 ± 3.8 vs. 23.5 ± 4.9 cm; 25.2 ± 6.2 vs. 22.7 ± 5.0 cm). However, middle-aged adults showed longer ground contact times (on average 36%), lower vertical ground reaction forces (36%) and hence lower average mechanical power (from lowest to highest box height: 2266 ± 563 vs. 1498 ± 545 W; 3563 ± 774 vs. 2222 ± 320 W; 4360 ± 658 vs. 2475 ± 528 W; 5008 ± 919 vs. 3034 ± 435 W) independent of box height. Further, leg stiffness was lower (48%) in middle-aged compared to younger adults for all jumping conditions and we found significant correlations between average mechanical power and leg stiffness (0.70 ≤ r ≤ 0.83; p < 0.01). Thus, while jumping performance appears to be unaffected when leg extensor muscle strength and tendon stiffness are maintained, the reduced muscular power output during lower limb multi-joint tasks seen with aging may be due to age-related changes in motor task execution strategy rather than due to muscle weakness.
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Affiliation(s)
- Matthias König
- School of Applied Sciences, Sport and Exercise Science Research Centre, London South Bank University, London, United Kingdom
| | - Svenja Hemmers
- Department of Mathematics and Technology, RheinAhrCampus Remagen, Koblenz University of Applied Sciences, Remagen, Germany
| | - Gaspar Epro
- School of Applied Sciences, Sport and Exercise Science Research Centre, London South Bank University, London, United Kingdom
| | - Christopher McCrum
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Nutrition and Movement Sciences, Maastricht University Medical Centre, Maastricht, Netherlands
- Institute of Movement and Sport Gerontology, German Sport University Cologne, Cologne, Germany
| | | | - Ulrich Hartmann
- Department of Mathematics and Technology, RheinAhrCampus Remagen, Koblenz University of Applied Sciences, Remagen, Germany
| | - Kiros Karamanidis
- School of Applied Sciences, Sport and Exercise Science Research Centre, London South Bank University, London, United Kingdom
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Holzer D, Epro G, McCrum C, Doerner J, Luetkens JA, Scheef L, Kukuk GM, Boecker H, Mierau A, Brüggemann GP, Maganaris CN, Karamanidis K. The role of muscle strength on tendon adaptability in old age. Eur J Appl Physiol 2018; 118:2269-2279. [PMID: 30088133 PMCID: PMC6182320 DOI: 10.1007/s00421-018-3947-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 07/20/2018] [Indexed: 01/28/2023]
Abstract
PURPOSE The purpose of the study was to determine: (1) the relationship between ankle plantarflexor muscle strength and Achilles tendon (AT) biomechanical properties in older female adults, and (2) whether muscle strength asymmetries between the individually dominant and non-dominant legs in the above subject group were accompanied by inter-limb AT size differences. METHODS The maximal generated AT force, AT stiffness, AT Young's modulus, and AT cross-sectional area (CSA) along its length were determined for both legs in 30 women (65 ± 7 years) using dynamometry, ultrasonography, and magnetic resonance imaging. RESULTS No between-leg differences in triceps surae muscle strength were identified between dominant (2798 ± 566 N) and non-dominant limb (2667 ± 512 N). The AT CSA increased gradually in the proximo-distal direction, with no differences between the legs. There was a significant correlation (P < 0.05) of maximal AT force with AT stiffness (r = 0.500) and Young's modulus (r = 0.414), but only a tendency with the mean AT CSA. However, region-specific analysis revealed a significant relationship between maximal AT force and the proximal part of the AT, indicating that this region is more likely to display morphological adaptations following an increase in muscle strength in older adults. CONCLUSIONS These findings demonstrate that maximal force-generation capabilities play a more important role in the variation of AT stiffness and material properties than in tendon CSA, suggesting that exercise-induced increases in muscle strength in older adults may lead to changes in tendon stiffness foremost due to alterations in material rather than in its size.
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Affiliation(s)
- D Holzer
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - G Epro
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, 103 Borough Rd, London, SE1 0AA, UK.
| | - C McCrum
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands.,Institute of Movement and Sport Gerontology, German Sport University Cologne, Cologne, Germany
| | - J Doerner
- Department of Radiology, University of Bonn, Bonn, Germany
| | - J A Luetkens
- Department of Radiology, University of Bonn, Bonn, Germany
| | - L Scheef
- Department of Radiology, University of Bonn, Bonn, Germany
| | - G M Kukuk
- Department of Radiology, University of Bonn, Bonn, Germany
| | - H Boecker
- Department of Radiology, University of Bonn, Bonn, Germany
| | - A Mierau
- Department of Exercise and Sport Science, LUNEX International University of Health, Exercise and Sports, Differdange, Luxembourg.,Institute of Movement and Neuroscience, German Sport University Cologne, Cologne, Germany
| | - G-P Brüggemann
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics, Medical Faculty, University of Cologne, Cologne, Germany
| | - C N Maganaris
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - K Karamanidis
- Sport and Exercise Science Research Centre, School of Applied Sciences, London South Bank University, 103 Borough Rd, London, SE1 0AA, UK
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Baxter JR, Piazza SJ. Plantarflexor moment arms estimated from tendon excursion in vivo are not strongly correlated with geometric measurements. J Biomech 2018; 77:201-205. [DOI: 10.1016/j.jbiomech.2018.06.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 06/04/2018] [Accepted: 06/19/2018] [Indexed: 11/15/2022]
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Fletcher JR, MacIntosh BR. Estimates of Achilles Tendon Moment Arm Length at Different Ankle Joint Angles: Effect of Passive Moment. J Appl Biomech 2018; 34:220-225. [PMID: 29873287 DOI: 10.1123/jab.2016-0263] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The length of a muscle's moment arm can be estimated noninvasively using ultrasound and the tendon excursion method. The main assumption with the tendon excursion method is that the force acting on the tendon during passive rotation is constant. However, passive force changes through the range of motion, and thus moment arm is underestimated. The authors attempted to account for passive force on the measurement of Achilles tendon moment arm using the tendon excursion method in 8 male and female runners. Tendon excursion was measured using ultrasound while the ankle was passively rotated at 0.17 rad·s-1. Moment arm was calculated at 5° intervals as the ratio of tendon displacement to joint rotation from 70° to 115°. Passive moment (MP) was measured using a dynamometer. The displacement attributable to MP was calculated by monitoring tendon displacement during a ramp isometric maximum contraction. MP was 5.7 (2.1) N·m at 70° and decreased exponentially from 70° to 90°. This resulted in MP-corrected moment arms that were significantly larger than uncorrected moment arms at joint angles where MP was present. Furthermore, MP-corrected moment arms did not change with ankle angle, which was not the case for uncorrected moment arms.
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