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John A Burne - One of the best experts on this subject based on the ideXlab platform.
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Golgi Tendon Organ reflex inhibition following manually applied acute static stretching
Journal of Sports Sciences, 2014Co-Authors: Kevin C Miller, John A BurneAbstract:AbstractGolgi Tendon Organ disinhibition may contribute to exercise-associated muscle cramp (henceforth referred to as “cramps”) genesis. Static stretching pre-exercise is prescribed to prevent cramps based on the assumption Golgi Tendon Organ inhibition remains elevated post-stretching. We determined whether stretching increased gastrocnemius Golgi Tendon Organ inhibition and, if so, the time course of this inhibition post-stretching. Twelve participants’ dominant limb medial gastrocnemius inhibition was measured before, and at 1, 5, 10, 15 and 30 min after investigators applied three, 1-min duration stretches. Participants maintained voluntary contraction intensities of 5% of their maximum while the Achilles Tendon was stimulated transcutaneously 50 times. Five-hundred millisecond epochs of raw electromyographic activity were band-pass filtered, full-wave rectified and averaged. An algorithm identified inhibitory points and calculated the area, maximum and duration of inhibition. Area of inhibition (F1,...
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acute static stretching does not affect Golgi Tendon Organ reflex inhibition
2013Co-Authors: Kevin C Miller, John A BurneAbstract:Clinical Significance Context: Golgi Tendon Organ (GTO) disinhibition is thought to contribute to exercise-associated muscle cramp (EAMC) genesis. Despite limited evidence of efficacy, acute static stretching is often prescribed to prevent EAMC based on the belief that stretching activates GTOs. Gastrocnemius GTO inhibition is highest when the gastrocnemius is in a lengthened position, but no research has examined the effect of acute stretching on GTO inhibition. Objectives: We asked: Does a single bout of acute static stretching increase gastrocnemius GTO inhibition? If so, how long does GTO inhibition stay elevated post-stretching? We hypothesized GTO inhibition would increase post-stretching but would return to pre-stretching levels within 5 minutes. Design: Repeated measures, cross-sectional. Setting: Laboratory. Patients or Other Participants: Six men (age=26±3 y; ht=179.5±4.1 cm; mass=81.8±13.4 kg) and six women (age=27±7 y; ht=163.4±4.9 cm; mass=64.4±9.6 kg). Interventions: Subjects’ dominant limb medial gastrocnemius GTO inhibition was tested before, immediately after, and 5, 10, 15, and 30 minutes post-stretching. With subjects long sitting, the investigators applied three, 1-minute bouts (1 minute of rest separating each bout) of static stretching to the gastrocnemius by placing the ankle into maximum dorsiflexion. To measure inhibition at each selected time interval, subjects maintained medial gastrocnemius contraction intensity at 5% of their maximum voluntary contraction EMG activity. While contracting, the Achilles Tendon was stimulated 50 times (rectangular pulses, 75 mA, 100 μs duration, 2-s interpulse interval). Pre, during, and post-stimulus EMG activity for the 50 trials at each measurement time were filtered, full-wave rectified, and averaged. An algorithm (implemented using MatLab software) identified inhibitory points and calculated the main outcome measures. Main Outcome Measures: Inhibition area (mV*ms-1), inhibition maximum (mV), and inhibition duration (ms). Outcome measures were normalized using 100 ms of pre-stimulus EMG activity. Repeated measures ANOVAs with Geisser-Greenhouse corrections were used to analyze data (α=0.05, NCSS v. 2007). Data are reported as means ± SD. Results: Inhibition area was unaffected by stretching at any time (F1,14=1.5, P=0.25; pre-stretch=0.07±0.09 mV*ms-1, immediately poststretching=0.07±0.10 mV*ms-1, 5 min post-stretching=0.06±0.08 mV*ms-1, 10 min poststretching=0.05±0.04 mV*ms-1, 15 minutes post-stretching=0.05±0.04 mV*ms-1, 30 minutes post-stretching=0.05±0.05 mV*ms-1). Inhibition maximum was also unaffected by stretching over time (F1,14=0.2, P=0.72; pre-stretch=0.0008±0.0009 mV, immediately poststretching=0.0008±0.0008 mV, 5 min post-stretching=0.0008±0.0007 mV, 10 min poststretching=0.0008±0.0007 mV, 15 minutes post-stretching=0.0008±0.0007 mV, 30 minutes poststretching=0.0008±0.0008 mV). Stretching also did not affect inhibition duration over time (F1,14=1.5, P=0.24; pre-stretch=3.5±2.8 ms, immediately post-stretching=3.3±2.8 ms, 5 min post-stretching=3.3±2.5 ms, 10 min post-stretching=2.8±1.6 ms, 15 minutes poststretching=2.7±1.7 ms, 30 minutes post-stretching=2.7±1.8 ms). Conclusions: A single bout of static stretching had no impact on GTO inhibition. Single bouts of static stretching are unlikely to prevent EAMC assuming the theory that GTO disinhibition contributes to EAMC genesis. The effect of chronic stretching programs on GTO inhibition warrants future examination. Experimental Design • Cross-sectional, laboratory study
Joriene C De Nooij - One of the best experts on this subject based on the ideXlab platform.
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regulating muscle spindle and Golgi Tendon Organ proprioceptor phenotypes
Current Opinion in Physiology, 2021Co-Authors: Niccolo Zampieri, Joriene C De NooijAbstract:Proprioception is an essential part of motor control. The main sensory subclasses that underlie this feedback control system - muscle spindle and Golgi Tendon Organ afferents - have been extensively characterized at a morphological and physiological level. More recent studies are beginning to reveal the molecular foundation for distinct proprioceptor subtypes, offering new insights into their developmental ontogeny and phenotypic diversity. This review intends to highlight some of these new findings.
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molecular development of muscle spindle and Golgi Tendon Organ sensory afferents revealed by single proprioceptor transcriptome analysis
bioRxiv, 2020Co-Authors: Katherine M Oliver, Danny M Florezpaz, Tudor C Badea, George Z Mentis, Vilas Menon, Joriene C De NooijAbstract:Anatomical and physiological analyses have long revealed differences between proprioceptive groups Ia, II, and Ib sensory neurons, yet the molecular correlates of these three muscle afferent subtypes remain unknown. We performed single cell RNA sequencing of genetically identified adult proprioceptors and, using unbiased bioinformatics approaches, detected five molecularly distinct neuronal clusters. Validation of cluster-specific transcripts in dorsal root ganglia (DRG) and skeletal muscle provides evidence these clusters correspond to functionally distinct muscle spindle (MS) or Golgi Tendon Organ (GTO) afferent proprioceptors. Remarkably, while we uncovered just one type of GTO afferents, four of the five clusters represent MS afferents, thus demonstrating a previously unappreciated diversity among these muscle proprioceptors. In vitro electrophysiological recordings reveal just two broadly distinct proprioceptor types, and suggest that the refinement of functional subtype diversity may occur along multiple axes of maturation. Lineage analysis between proprioceptor transcriptomes at different developmental stages show little or no correlation for transcripts that define adult MS or GTO afferents, supporting the idea that proprioceptor subtype identity emerges late in development. Together, our data provide the first comprehensive molecular signature for groups Ia and II MS afferents and group Ib GTO afferents, and offer new strategies for genetic interrogation of the role of these individual proprioceptor subtypes in regulating voluntary motor behavior.
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a role for sensory end Organ derived signals in regulating muscle spindle proprioceptor phenotype
The Journal of Neuroscience, 2019Co-Authors: Dawei Wu, Ira Schieren, Yingzhi Qian, Thomas M Jessell, Chaolin Zhang, Joriene C De NooijAbstract:Proprioceptive feedback from Group Ia/II muscle spindle afferents and Group Ib Golgi Tendon afferents is critical for the normal execution of most motor tasks, yet how these distinct proprioceptor subtypes emerge during development remains poorly understood. Using molecular genetic approaches in mice of either sex, we identified 24 transcripts that have not previously been associated with a proprioceptor identity. Combinatorial expression analyses of these markers reveal at least three molecularly distinct proprioceptor subtypes. In addition, we find that 12 of these transcripts are expressed well after proprioceptors innervate their respective sensory receptors, and expression of three of these markers, including the heart development molecule Heg1 , is significantly reduced in mice that lack muscle spindles. These data reveal Heg1 as a putative marker for proprioceptive muscle spindle afferents. Moreover, they suggest that the phenotypic specialization of functionally distinct proprioceptor subtypes depends, in part, on extrinsic sensory receptor Organ-derived signals. SIGNIFICANCE STATEMENT Sensory feedback from muscle spindle (MS) and Golgi Tendon Organ (GTO) sensory end Organs is critical for normal motor control, but how distinct MS and GTO afferent sensory neurons emerge during development remains poorly understood. Using (bulk) transcriptome analysis of genetically identified proprioceptors, this work reveals molecular markers for distinct proprioceptor subsets, including some that appear selectively expressed in MS afferents. Detailed analysis of the expression of these transcripts provides evidence that MS/GTO afferent subtype phenotypes may, at least in part, emerge through extrinsic, sensory end Organ-derived signals.
Kevin C Miller - One of the best experts on this subject based on the ideXlab platform.
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Golgi Tendon Organ reflex inhibition following manually applied acute static stretching
Journal of Sports Sciences, 2014Co-Authors: Kevin C Miller, John A BurneAbstract:AbstractGolgi Tendon Organ disinhibition may contribute to exercise-associated muscle cramp (henceforth referred to as “cramps”) genesis. Static stretching pre-exercise is prescribed to prevent cramps based on the assumption Golgi Tendon Organ inhibition remains elevated post-stretching. We determined whether stretching increased gastrocnemius Golgi Tendon Organ inhibition and, if so, the time course of this inhibition post-stretching. Twelve participants’ dominant limb medial gastrocnemius inhibition was measured before, and at 1, 5, 10, 15 and 30 min after investigators applied three, 1-min duration stretches. Participants maintained voluntary contraction intensities of 5% of their maximum while the Achilles Tendon was stimulated transcutaneously 50 times. Five-hundred millisecond epochs of raw electromyographic activity were band-pass filtered, full-wave rectified and averaged. An algorithm identified inhibitory points and calculated the area, maximum and duration of inhibition. Area of inhibition (F1,...
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acute static stretching does not affect Golgi Tendon Organ reflex inhibition
2013Co-Authors: Kevin C Miller, John A BurneAbstract:Clinical Significance Context: Golgi Tendon Organ (GTO) disinhibition is thought to contribute to exercise-associated muscle cramp (EAMC) genesis. Despite limited evidence of efficacy, acute static stretching is often prescribed to prevent EAMC based on the belief that stretching activates GTOs. Gastrocnemius GTO inhibition is highest when the gastrocnemius is in a lengthened position, but no research has examined the effect of acute stretching on GTO inhibition. Objectives: We asked: Does a single bout of acute static stretching increase gastrocnemius GTO inhibition? If so, how long does GTO inhibition stay elevated post-stretching? We hypothesized GTO inhibition would increase post-stretching but would return to pre-stretching levels within 5 minutes. Design: Repeated measures, cross-sectional. Setting: Laboratory. Patients or Other Participants: Six men (age=26±3 y; ht=179.5±4.1 cm; mass=81.8±13.4 kg) and six women (age=27±7 y; ht=163.4±4.9 cm; mass=64.4±9.6 kg). Interventions: Subjects’ dominant limb medial gastrocnemius GTO inhibition was tested before, immediately after, and 5, 10, 15, and 30 minutes post-stretching. With subjects long sitting, the investigators applied three, 1-minute bouts (1 minute of rest separating each bout) of static stretching to the gastrocnemius by placing the ankle into maximum dorsiflexion. To measure inhibition at each selected time interval, subjects maintained medial gastrocnemius contraction intensity at 5% of their maximum voluntary contraction EMG activity. While contracting, the Achilles Tendon was stimulated 50 times (rectangular pulses, 75 mA, 100 μs duration, 2-s interpulse interval). Pre, during, and post-stimulus EMG activity for the 50 trials at each measurement time were filtered, full-wave rectified, and averaged. An algorithm (implemented using MatLab software) identified inhibitory points and calculated the main outcome measures. Main Outcome Measures: Inhibition area (mV*ms-1), inhibition maximum (mV), and inhibition duration (ms). Outcome measures were normalized using 100 ms of pre-stimulus EMG activity. Repeated measures ANOVAs with Geisser-Greenhouse corrections were used to analyze data (α=0.05, NCSS v. 2007). Data are reported as means ± SD. Results: Inhibition area was unaffected by stretching at any time (F1,14=1.5, P=0.25; pre-stretch=0.07±0.09 mV*ms-1, immediately poststretching=0.07±0.10 mV*ms-1, 5 min post-stretching=0.06±0.08 mV*ms-1, 10 min poststretching=0.05±0.04 mV*ms-1, 15 minutes post-stretching=0.05±0.04 mV*ms-1, 30 minutes post-stretching=0.05±0.05 mV*ms-1). Inhibition maximum was also unaffected by stretching over time (F1,14=0.2, P=0.72; pre-stretch=0.0008±0.0009 mV, immediately poststretching=0.0008±0.0008 mV, 5 min post-stretching=0.0008±0.0007 mV, 10 min poststretching=0.0008±0.0007 mV, 15 minutes post-stretching=0.0008±0.0007 mV, 30 minutes poststretching=0.0008±0.0008 mV). Stretching also did not affect inhibition duration over time (F1,14=1.5, P=0.24; pre-stretch=3.5±2.8 ms, immediately post-stretching=3.3±2.8 ms, 5 min post-stretching=3.3±2.5 ms, 10 min post-stretching=2.8±1.6 ms, 15 minutes poststretching=2.7±1.7 ms, 30 minutes post-stretching=2.7±1.8 ms). Conclusions: A single bout of static stretching had no impact on GTO inhibition. Single bouts of static stretching are unlikely to prevent EAMC assuming the theory that GTO disinhibition contributes to EAMC genesis. The effect of chronic stretching programs on GTO inhibition warrants future examination. Experimental Design • Cross-sectional, laboratory study
Dinant A Kistemaker - One of the best experts on this subject based on the ideXlab platform.
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control of position and movement is simplified by combined muscle spindle and Golgi Tendon Organ feedback
Journal of Neurophysiology, 2013Co-Authors: Dinant A Kistemaker, Arthur J Van Soest, Jeremy D Wong, Isaac Kurtzer, Paul L GribbleAbstract:Whereas muscle spindles play a prominent role in current theories of human motor control, Golgi Tendon Organs (GTO) and their associated Tendons are often neglected. This is surprising since there is ample evidence that both Tendons and GTOs contribute importantly to neuromusculoskeletal dynamics. Using detailed musculoskeletal models, we provide evidence that simple feedback using muscle spindles alone results in very poor control of joint position and movement since muscle spindles cannot sense changes in Tendon length that occur with changes in muscle force. We propose that a combination of spindle and GTO afferents can provide an estimate of muscle-Tendon complex length, which can be effectively used for low-level feedback during both postural and movement tasks. The feasibility of the proposed scheme was tested using detailed musculoskeletal models of the human arm. Responses to transient and static perturbations were simulated using a 1-degree-of-freedom (DOF) model of the arm and showed that the combined feedback enabled the system to respond faster, reach steady state faster, and achieve smaller static position errors. Finally, we incorporated the proposed scheme in an optimally controlled 2-DOF model of the arm for fast point-to-point shoulder and elbow movements. Simulations showed that the proposed feedback could be easily incorporated in the optimal control framework without complicating the computation of the optimal control solution, yet greatly enhancing the system's response to perturbations. The theoretical analyses in this study might furthermore provide insight about the strong physiological couplings found between muscle spindle and GTO afferents in the human nervous system.
Richard T Nichols - One of the best experts on this subject based on the ideXlab platform.
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evaluating intermuscular Golgi Tendon Organ feedback with twitch contractions
The Journal of Physiology, 2019Co-Authors: Mark A Lyle, Richard T NicholsAbstract:KEY POINTS Golgi Tendon Organ feedback has been evaluated most frequently using electrical stimulation of peripheral nerves, which is not a physiological or selective stimulus for Golgi Tendon Organs. Golgi Tendon Organs are most responsive to active muscle contractions. This study provides evidence that muscle stimulation evoked twitches - a physiological stimulus for Golgi Tendon Organs - induces intermuscular effects most likely due to mechanical activation of Golgi Tendon Organ feedback and not direct activation of sensory axons. The results demonstrate that twitch contractions are a feasible non-invasive approach that can be used to advance understanding of the functional role of Golgi Tendon Organ feedback. ABSTRACT Force feedback from Golgi Tendon Organs (GTOs) has widespread intermuscular projections mediated by interneurons that share inputs from muscle spindles, among others. Because current methods to study GTO circuitry (nerve stimulation or muscle stretch) also activate muscle spindle afferents, the selective role of GTOs remains uncertain. Here, we tested the hypothesis that intramuscular stimulation evoked twitch contractions could be used to naturally bias activation of GTOs and thus evaluate their intermuscular effects in decerebrate cats. This was achieved by comparing the effects of twitch contractions and stretches as donor inputs onto the motor output of recipient muscles. Donor-recipient pairs evaluated included those already known in the cat to receive donor excitatory muscle spindle feedback only, inhibitory GTO feedback only, and both excitatory spindle and inhibitory GTO effects. Muscle stretch, but not twitch contractions, evoked excitation onto recipient muscles with muscle spindle afferent inputs only. Both donor muscle stretch and twitch contractions inhibited a recipient muscle with GTO projections only. In a recipient muscle that receives both muscle spindle and GTO projections, donor muscle stretch evoked both excitatory and inhibitory effects, whereas twitch contractions evoked inhibitory effects only. These data support the hypothesis that muscle stimulation evoked contractions can induce intermuscular effects most consistent with mechanical GTO receptor activation and not direct activation of sensory axons. We propose this approach can be used to evaluate GTO circuitry more selectively than muscle stretch or nerve stimulation and can be adapted to study GTO feedback non-invasively in freely moving cats and humans.