0000000000253340

AUTHOR

Kirsten Albracht

0000-0002-4271-2511

showing 6 related works from this author

Modulation of muscle-tendon interaction in the human triceps surae during an energy dissipation task.

2017

The compliance of elastic elements allows muscles to dissipate energy safely during eccentric contractions. This buffering function is well documented in animal models but our understanding of its mechanism in humans is confined to non-specific tasks, requiring a subsequent acceleration of the body. The present study aimed to examine the behaviour of the human triceps surae muscle-tendon unit (MTU) during a pure energy dissipation task, under two loading conditions. Thirty-nine subjects performed a single-leg landing task, with- and without added mass. Ultrasound measurements were combined with 3D kinematics and kinetics to determine instantaneous length changes of MTUs, muscle fascicles, A…

030110 physiology0301 basic medicineAdultMaleMaterials sciencePhysiologyQP301.H75_Physiology._Sport.muscle-tendonStrain (injury)KinematicsAquatic ScienceConcentricMotor ActivityAchilles TendonRC120003 medical and health sciencesYoung Adult0302 clinical medicinemedicineHumansta315Muscle SkeletalMolecular BiologyEcology Evolution Behavior and SystematicsSoleus muscleAchilles tendonAnatomyFasciclemedicine.diseaseTendonBiomechanical PhenomenamodulationKineticsmedicine.anatomical_structureInsect ScienceAnimal Science and Zoologymedicine.symptom030217 neurology & neurosurgeryMuscle contractionMuscle ContractionThe Journal of experimental biology
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Effect of Training-Induced Changes in Achilles Tendon Stiffness on Muscle–Tendon Behavior During Landing

2018

During rapid deceleration of the body, tendons buffer part of the elongation of the muscle–tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle–tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarf…

musculoskeletal diseasesenergy dissipationtendon propertiesPhysiologyQP301.H75_Physiology._Sport.Strain (injury)Isometric exerciseKinematicslcsh:Physiologyjänteet03 medical and health sciencesEccentric muscle contractionstiffness0302 clinical medicinePhysiology (medical)jäykkyysmedicineenergy absorptionta315Original ResearchAchilles tendonlcsh:QP1-981business.industryUltrasoundmechanical buffer030229 sport sciencesFasciclemedicine.diseasemusculoskeletal systemTendonAchilles tendonmedicine.anatomical_structurevoimaharjoittelukantajännebusiness030217 neurology & neurosurgeryBiomedical engineering
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Distinct muscle-tendon interaction during running at different speeds and in different loading conditions.

2019

The interaction between the Achilles tendon and the triceps surae muscles seems to be modulated differently with various task configurations. Here we tested the hypothesis that the increased forces and ankle joint work during running under contrasting conditions (altered speed or load) would be met by different, time-dependent adjustments at the muscle-tendon level. Ultrasonography, electromyography, kinematics, and ground reaction force measurements were used to examine Achilles tendon, gastrocnemius, and soleus muscle mechanics in 16 runners in four different running conditions, consisting of a combination of two different speeds (preferred and +20% of preferred speed) and two loading co…

AdultMalePhysiologyComputer scienceAchilles TendonRunning03 medical and health sciences0302 clinical medicinePhysiology (medical)medicineHumansMuscle SkeletalBiological sciencesGaitUltrasonographyLoad carriageAchilles tendonbusiness.industryWork (physics)030229 sport sciencesStructural engineeringmusculoskeletal systemTendonBiomechanical Phenomenamedicine.anatomical_structurebusinessMuscle architecture030217 neurology & neurosurgeryAnkle JointMuscle ContractionJournal of applied physiology (Bethesda, Md. : 1985)
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Ultrasound-based testing of tendon mechanical properties: a critical evaluation.

2015

In the past 20 years, the use of ultrasound-based methods has become a standard approach to measure tendon mechanical properties in vivo. Yet the multitude of methodological approaches adopted by various research groups probably contribute to the large variability of reported values. The technique of obtaining and relating tendon deformation to tensile force in vivo has been applied differently, depending on practical constraints or scientific points of view. Divergence can be seen in 1) methodological considerations, such as the choice of anatomical features to scan and to track, force measurements, or signal synchronization; and 2) in physiological considerations related to the viscoelas…

Pathologymedicine.medical_specialtyPhysiologybusiness.industryUltrasoundMeasure (physics)TendonBiomechanical PhenomenaTendonsmedicine.anatomical_structurePhysiology (medical)medicineHumansAponeurosisbusinessBiomedical engineeringUltrasonographyJournal of applied physiology (Bethesda, Md. : 1985)
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Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running

2019

Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric single-leg plantarflexion co…

musculoskeletal diseasesmedicine.medical_specialtyAnatomy and Physiologytendon propertiesachilles tendonlcsh:MedicineIsometric exerciseGeneral Biochemistry Genetics and Molecular BiologyjuoksuStiffnessRunning03 medical and health sciences0302 clinical medicinePhysical medicine and rehabilitationArchitectural gear ratioSoleusgastrocnemiusjäykkyysmedicineGastrocnemiusta315Training periodsoleusarchitectural gear ratioAchilles tendonbusiness.industryGeneral Neurosciencelcsh:RStiffness030229 sport sciencesGeneral MedicineFascicleKinesiologymusculoskeletal systemTendonTendon propertiesTendon strainAchilles tendonmedicine.anatomical_structureArchitectural gear ratiokantajännemedicine.symptomGeneral Agricultural and Biological Sciencesbusiness030217 neurology & neurosurgeryPeerJ
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Distinct muscle-tendon interaction during running at different speeds and in different loading conditions

2019

The interaction between the Achilles tendon and the triceps surae muscles seems to be modulated differently with various task configurations. Here we tested the hypothesis that the increased forces and ankle joint work during running under contrasting conditions (altered speed or load) would be met by different, time-dependent adjustments at the muscle-tendon level. Ultrasonography, electromyography, kinematics, and ground reaction force measurements were used to examine Achilles tendon, gastrocnemius, and soleus muscle mechanics in 16 runners in four different running conditions, consisting of a combination of two different speeds (preferred and +20% of preferred speed) and two loading con…

locomotionmuscle architectureachilles tendonload carriagelihaksetbiomekaniikkakantajännemusculoskeletal systemjuoksu
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