{ "types" : { "Bookmark" : { "pluralLabel" : "Bookmarks" }, "Publication" : { "pluralLabel" : "Publications" }, "GoldStandardPublication" : { "pluralLabel" : "GoldStandardPublications" }, "GoldStandardBookmark" : { "pluralLabel" : "GoldStandardBookmarks" }, "Tag" : { "pluralLabel" : "Tags" }, "User" : { "pluralLabel" : "Users" }, "Group" : { "pluralLabel" : "Groups" }, "Sphere" : { "pluralLabel" : "Spheres" } }, "properties" : { "count" : { "valueType" : "number" }, "date" : { "valueType" : "date" }, "changeDate" : { "valueType" : "date" }, "url" : { "valueType" : "url" }, "id" : { "valueType" : "url" }, "tags" : { "valueType" : "item" }, "user" : { "valueType" : "item" } }, "items" : [ { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/213d1c527b422f0c2fbfb26d98885b1f6/inspo5", "tags" : [ "Blebbistatin","damping","Cross-bridge","Mechanosensing","Signaling","Mechanical","Contractile","power","Muscle","behaviour","block","Sarcomere" ], "intraHash" : "13d1c527b422f0c2fbfb26d98885b1f6", "interHash" : "1a1ddb22b3fc4a98ff638b17f957aa71", "label" : "Force re-development after shortening reveals a role for titin in stretch-shortening performance enhancement in skinned muscle fibres", "user" : "inspo5", "description" : "", "date" : "2024-08-28 13:42:24", "changeDate" : "2025-02-11 20:09:58", "count" : 6, "pub-type": "article", "journal": "Journal of Experimental Biology","publisher":"The Company of Biologists", "year": "2024", "url": "http://dx.doi.org/10.1242/jeb.247377", "author": [ "André Tomalka","Sven Weidner","Daniel Hahn","Wolfgang Seiberl","Tobias Siebert" ], "authors": [ {"first" : "André", "last" : "Tomalka"}, {"first" : "Sven", "last" : "Weidner"}, {"first" : "Daniel", "last" : "Hahn"}, {"first" : "Wolfgang", "last" : "Seiberl"}, {"first" : "Tobias", "last" : "Siebert"} ], "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "abstract": "Stretch-shortening cycles (SSCs) involve muscle lengthening (eccentric contractions) instantly followed by shortening (concentric contractions). This combination enhances force, work, and power output compared to pure shortening (SHO), which is known as SSC-effect. Recent evidence indicates both cross-bridge-based (XB) and non-cross-bridge-based (non-XB, e.g., titin) structures contribute to this effect. This study analyzed force re-development following SSCs and SHO to gain further insight into the roles of XB and non-XB structures regarding the SSC-effect. Experiments were conducted on rat soleus muscle fibres (n=16) with different SSC velocities (30%, 60%, 85% of maximum shortening velocity) and constant stretch-shortening magnitudes (18% of optimum length). The XB inhibitor blebbistatin was used to distinguish between XB and non-XB contributions to force generation. Results showed SSCs led to significantly greater (1.02±.15 vs. 0.68±.09 [ΔF/Δt]; t(62)=8.61, p<.001, d=2.79) and faster (75 ms vs. 205 [ms]; t(62) = -6.37, p<.001, d=-1.48) force re-development compared to SHO in the control treatment. In the blebbistatin treatment, SSCs still resulted in greater (.11±.03 vs. .06±.01 [ΔF/Δt]; t(62) = 8.00, p<.001, d=2.24) and faster (3010±1631 vs. 7916±3230 [ms]; t(62) = -8.00, p<.001, d=-1.92) force re-development compared to SHO. These findings deepen our understanding of the SSC-effect, underscoring the involvement of non-XB structures like titin in modulating force production. This modulation likely involves complex mechanosensory coupling from stretch to signal transmission during muscle contraction.", "issn" : "1477-9145", "doi" : "10.1242/jeb.247377", "bibtexKey": "Tomalka_2024" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/20b8a2822ba7baaca10669289c107bd9c/inspo5", "tags" : [ "dynamics","muscle","work","mechanical","damping","intrinsic","stiffness","properties" ], "intraHash" : "0b8a2822ba7baaca10669289c107bd9c", "interHash" : "a826d07e2f8c83bb1b8a903cbbcccde6", "label" : "Muscle preflex response to perturbations in locomotion: In vitro experiments and simulations with realistic boundary conditions", "user" : "inspo5", "description" : "", "date" : "2023-05-16 10:24:04", "changeDate" : "2023-05-16 10:24:04", "count" : 1, "pub-type": "article", "journal": "Frontiers in Bioengineering and Biotechnology", "year": "2023", "url": "https://www.frontiersin.org/articles/10.3389/fbioe.2023.1143926/full", "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "volume": "11","abstract": "Musculoskeletal disorders (MSD) are a widespread problem, often regarding the lumbar region. Exoskeletons designed to support the lower back could be used in physically demanding professions with the intention of reducing the strain on the musculoskeletal system, e.g., by lowering task-related muscle activation. The present study aims to investigate the effect of an active exoskeleton on back muscle activity when lifting weights. Within the framework of the study, 14 subjects were asked to lift a 15 kg box with and without an active exoskeleton which allows the adjustment of different levels of support, while the activity of their M. erector spinae (MES) was measured using surface electromyography. Additionally, the subjects were asked about their overall rating of perceived exertion (RPE) during lifting under various conditions. Using the exoskeleton with the maximum level of support, the muscle activity was significantly lower than without exoskeleton. A significant correlation was found between the exoskeleton\u2019s support level and the reduction of MES activity. The higher the support level, the lower the observed muscle activity. Furthermore, when lifting with the maximum level of support, RPE was found to be significantly lower than without exoskeleton too. A reduction in the MES activity indicates actual support for the movement task and might indicate lower compression forces in the lumbar region. It is concluded that the active exoskeleton supports people noticeably when lifting heavy weights. Exoskeletons seem to be a powerful tool for reducing load during physically demanding jobs and thus, their use might be helpful in lowering the risk of MSD.", "language" : "English", "doi" : "10.3389/fbioe.2023.1143926", "bibtexKey": "siebert2023muscle" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/261fedf1d36ba0727ea70b4ebe0ccf080/inspo5", "tags" : [ "contractile","mechanical","damping","enhancement","performance","contractions","stretch","shortening","PN2A-1","muscle","power","eccentric","behavior" ], "intraHash" : "61fedf1d36ba0727ea70b4ebe0ccf080", "interHash" : "2c45e90e696b09a75331acf51aae74e4", "label" : "Power Amplification Increases With Contraction Velocity During Stretch-Shortening Cycles of Skinned Muscle Fibers", "user" : "inspo5", "description" : "", "date" : "2022-07-19 11:10:29", "changeDate" : "2024-07-05 14:53:03", "count" : 7, "pub-type": "article", "journal": "Frontiers in Physiology","publisher":"Frontiers Media SA", "year": "2021", "url": "https://doi.org/10.3389%2Ffphys.2021.644981", "author": [ "André Tomalka","Sven Weidner","Daniel Hahn","Wolfgang Seiberl","Tobias Siebert" ], "authors": [ {"first" : "André", "last" : "Tomalka"}, {"first" : "Sven", "last" : "Weidner"}, {"first" : "Daniel", "last" : "Hahn"}, {"first" : "Wolfgang", "last" : "Seiberl"}, {"first" : "Tobias", "last" : "Siebert"} ], "volume": "12","abstract": "Muscle force, work, and power output during concentric contractions (active muscle shortening) are increased immediately following an eccentric contraction (active muscle lengthening). This increase in performance is known as the stretch-shortening cycle (SSC)-effect. Recent findings demonstrate that the SSC-effect is present in the sarcomere itself. More recently, it has been suggested that cross-bridge (XB) kinetics and non-cross-bridge (non-XB) structures (e.g., titin and nebulin) contribute to the SSC-effect. As XBs and non-XB structures are characterized by a velocity dependence, we investigated the impact of stretch-shortening velocity on the SSC-effect. Accordingly, we performed in vitro isovelocity ramp experiments with varying ramp velocities (30, 60, and 85% of maximum contraction velocity for both stretch and shortening) and constant stretch-shortening magnitudes (17% of the optimum sarcomere length) using single skinned fibers of rat soleus muscles. The different contributions of XB and non-XB structures to force production were identified using the XB-inhibitor Blebbistatin. We show that (i) the SSC-effect is velocity-dependent\u2014since the power output increases with increasing SSC-velocity. (ii) The energy recovery (ratio of elastic energy storage and release in the SSC) is higher in the Blebbistatin condition compared with the control condition. The stored and released energy in the Blebbistatin condition can be explained by the viscoelastic properties of the non-XB structure titin. Consequently, our experimental findings suggest that the energy stored in titin during the eccentric phase contributes to the SSC-effect in a velocity-dependent manner.", "doi" : "https://doi.org/10.3389/fphys.2021.644981", "bibtexKey": "Tomalka_2021" } ] }