Contractile force is transmitted to the skeleton through tendons and aponeuroses, and, although it appreciated that mechanocharacteristics of these tissues play an important role for movement performance with respect energy storage, association between tendon mechanical properties contractile muscle output during high-force tasks remains elusive. The purpose study was investigate relation connective tissue in maximal isometric dynamic actions. Sixteen trained men participated study. vastus...

The mechanical characteristics of the human free tendon and aponeurosis, in vivo, remains largely unknown. present study evaluated longitudinal displacement separate Achilles distal (deep) aponeurosis medial gastrocnemius muscle during voluntary isometric contraction.Ultrasonography-obtained tendon-aponeurosis complex, electromyography gastrocnemius, soleus, dorsiflexor muscles, joint angular rotation were recorded plantarflexion (n = 5). Tendon cross-sectional area, moment arm segment...

The purpose of this study was to examine patellar tendon (PT) size and mechanical properties in subjects with a side-to-side strength difference > or =15% due sport-induced loading. Seven elite fencers badminton players were included. Cross-sectional area (CSA) the PT obtained from MRI ultrasonography-based measurement tibial movement together force during isometric contractions used estimate bilaterally. We found that distal PT, but not mid-tendon, CSA greater on lead extremity compared...

The human triceps surae muscle-tendon complex is a unique structure with three separate muscle compartments that merge via their aponeuroses into the Achilles tendon. mechanical function and properties of these structures during muscular contraction are not well understood. purpose study was to investigate extent which differential displacement occurs between medial gastrocnemius (MG) soleus (Sol) muscles plantar flexion. Eight subjects (mean +/- SD; age 30 7 yr, body mass 76.8 5.5 kg,...

The purpose of this study was to test the hypothesis that remodeling skeletal muscle extracellular matrix (ECM) is involved in protecting human against injury. Biopsies were obtained from medial gastrocnemius muscles after a single bout electrical stimulation (B) or repeated (RB) 30 d later, (RBc). A biopsy collected control leg for comparison with stimulated leg. Satellite cell content, tenascin C, and regeneration assessed by immunohistochemistry; real-time PCR used measure mRNA levels...

Abstract The primary aim of our study was to validate the assessment myonuclear and satellite cell number in biopsies from human skeletal muscle. We found that 25 type I II fibers are sufficient estimate mean myonuclei per fiber. In contrast, cells improved when more were included. Second, we report small differences counting using CD56 Pax7 antibodies can be attributed different staining profiles. Third, provide support for use Ki67 evaluating proportion active cells. observed very few (up...

Background Although differences in mechanical properties between symptomatic and healthy tendons have been observed for the Achilles tendon, impact of tendinopathy on patellar tendon mechanics is not fully documented. The aim present case–control study was to assess jump performance elite athletes with without tendinopathy. Methods We identified 17 male volleyball players 18 matched controls from a 5-year prospective cohort junior players. Outcome variables included three measures maximal...

We examined whether long‐term habitual training (a) was associated with differences in structural and mechanical properties tendon women (b) yielded different men women. Ten male runners, 10 female runners non‐runners were tested. Tendon cross‐sectional area (CSA) length of the patellar Achilles determined MRI. Ultrasonography‐based measurement elongation force during isometric contractions provided properties. Distal CSAs greater than proximal part all three groups ( P <0.05)....

The exact mechanical function of synergist muscles within a human limb in vivo is not well described. Recent studies indicate the existence interaction between muscle actuators that may have functional significance and further play role for injury mechanisms. purpose present study was to investigate if intermuscular force transmission occurs plantarflexor vivo. Seven subjects performed four types either active contractile tasks or passive joint manipulations: knee extension, voluntary...

Fascicle angle (FA) is suggested to increase as a result of fiber hypertrophy and furthermore serve the explanatory link in discrepancy relative adaptations anatomical cross-sectional area (CSA) CSA after resistance training (RT). In contrast RT, effects endurance on FA are unclear. The purpose this study was therefore investigate compare longitudinal either progressive (END, n = 7) or RT (n young untrained men FA, CSA, CSA. Muscle morphological measures included assessment vastus lateralis...

The effect of a period passive movement training on angiogenic factors and capillarization in skeletal muscle was examined. Seven young males were subjected to for 90 min, four times per week motor-driven knee extensor device that extended one passively at 80 cycles min₋₁. other leg used as control. Muscle biopsies obtained from m. v. lateralis both legs before well after 2 4 weeks training. After the period, active exercise performed with legs, interstitial fluid sampled microdialysis...

It is unknown whether muscle damage at the level of sarcomere can be induced without lengthening contractions. To investigate this, we designed a study where seven young, healthy men underwent 30 min repeated electrical stimulated contraction m. gastrocnemius medialis, with ankle and leg locked in fixed position. Two biopsies were collected 48 h later: one from contralateral as control. The analyzed immunohistochemically for inflammatory cell infiltration intermediate filament disruption....

Due to the complexity of movement in cross-country skiing (XCS), muscle activation patterns are not well elucidated. Previous studies have applied surface electromyography (SEMG); however, recent gains three-dimensional (3D) imaging techniques such as positron emission tomography (PET) rendered an alternative approach investigate activation. The purpose present study was examine use during double poling (DP) at two work intensities by PET. Eight male subjects performed 20-min DP bouts on...

During human movement, the muscle and tendinous structures interact as a mechanical system in which forces are generated transmitted to bone energy is stored released optimize function economy of movement and/or reduce risk injury. The present review addresses certain aspects how anatomical design material properties force-transmitting tissues contribute muscle-tendon unit thus overall function. force-bearing examined from structural macroscopic point view down nanoscale level collagen...

This study examined the effects of 24 wk daily static stretching plantarflexors (unilateral 4 × 60-s stretching, whereas contralateral leg served as a control; n = 26) on joint range motion (ROM), muscle-tendon unit morphological and mechanical properties, neural activation, contractile function.Torque-angle/velocity was obtained in passive active conditions using isokinetic dynamometry, morphology properties were ultrasonography.After intervention, ROM increased (stretching, +11° ± 7°;...

The mechanical properties of the human vastus lateralis (VL) tendon-aponeurosis complex were investigated in eight male subjects. Knee extensor force, knee joint angle, and corresponding longitudinal VL aponeurosis displacement monitored synchronously during graded (10-s) maximal isometric extension contractions. Displacement observed conditions may be regarded as an expression deformation tissues distal to measurement site. Furthermore, was measured passive (90-75 degrees ), used correct...

The metabolic activity of tendinous tissues has traditionally been considered to be limited magnitude. However, recent studies have suggested that glucose uptake increases in the force-transmitting as a response contractile loading, which turn indicates an elevated tissue metabolism. purpose present study was investigate whether such mechanism could observed for human Achilles tendon following tensile loading. Six subjects participated study. Unilateral loading applied by 25-min intermittent...