TY - JOUR AU - Papegaaij, S AU - Baudry, S AU - Négyesi, János AU - Taube, W AU - Hortobágyi, Tibor TI - Intracortical inhibition in the soleus muscle is reduced during the control of upright standing in both young and old adults JF - EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY J2 - EUR J APPL PHYSIOL VL - 116 PY - 2016 IS - 5 SP - 959 EP - 967 PG - 9 SN - 1439-6319 DO - 10.1007/s00421-016-3354-6 UR - https://m2.mtmt.hu/api/publication/3054423 ID - 3054423 AB - PURPOSE: In a previous study, we reported that a short-interval intracortical inhibition (SICI) decreases in old but not in young adults when standing on foam vs. a rigid surface. Here, we examined if such an age by task difficulty interaction in motor cortical excitability also occurs in easier standing tasks. METHODS: Fourteen young (23 +/- 2.7 years) and fourteen old (65 +/- 4.1 years) adults received transcranial magnetic brain stimulation and peripheral nerve stimulation, while they stood with or without support on a force platform. RESULTS: In the soleus, we found that SICI was lower in unsupported (35 % inhibition) vs. supported (50 %) standing (p = 0.007) but similar in young vs. old adults (p = 0.591). In the tibialis anterior, SICI was similar between conditions (p = 0.597) but lower in old (52 %) vs. young (72 %) adults (p = 0.030). Age and standing with or without support did not affect the Hoffmann reflex in the soleus. CONCLUSIONS: The current data suggest that the motor cortex is involved in standing control, and that its role becomes more prominent with an increase in task difficulty. LA - English DB - MTMT ER - TY - JOUR AU - Di Giminiani, R AU - Masedu, F AU - Padulo, J AU - Tihanyi, József AU - Valenti, M TI - The EMG activity-acceleration relationship to quantify the optimal vibration load when applying synchronous whole-body vibration JF - JOURNAL OF ELECTROMYOGRAPHY AND KINESIOLOGY J2 - J ELECTROMYOGR KINES VL - 25 PY - 2015 IS - 6 SP - 853 EP - 859 PG - 7 SN - 1050-6411 DO - 10.1016/j.jelekin.2015.09.004 UR - https://m2.mtmt.hu/api/publication/2990192 ID - 2990192 AB - Purpose: To date are lacking methodological approaches to individualizing whole-body vibration (WBV) intensity. The aim of this study was: (1) to determine the surface-electromyography-root-mean-square (sEMGRMS)-acceleration load relationship in the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), lateral gastrocnemius (LG) muscles during synchronous WBV, and (2) to assess the reliability of the acceleration corresponding to the maximal sEMGRMS. Methods: Twenty-five sportsman voluntarily took part in this study with a single-group, repeated-measures design. All subjects postured themselves in an isometric half-squat during nine trials in the following conditions: no vibrations and random vibrations of different acceleration loads (from 0.12 to 5.72g). Results: The sEMGRMS were dependent on the acceleration loads in the VL (p=0.0001), LG (p=0.0001) and VM (p=0.011) muscles; while RF was not affected by the acceleration loads (p=0.508). The comparisons among the sEMGRMS-accelerations relationships revealed a significant difference between the LG and the others muscles (p=0.001). No significant difference was found between the different thigh muscles (p>0.05). The intra-class correlation coefficient ranged from 0.87 to 0.99 for the measurements performed on the LG, VL and VM. Conclusions: The sEMGRMS-acceleration relationship in the VL, VM and LG is a reliable test to individualize the WBV intervention. © 2015 Elsevier Ltd. LA - English DB - MTMT ER - TY - JOUR AU - Mosaferi Ziaaldini, Mohammad AU - Koltai, Erika AU - Csende, Zsolt AU - Goto, Sataro AU - Boldogh, Istvan AU - Taylor, Albert W AU - Radák, Zsolt TI - Exercise training increases anabolic and attenuates catabolic and apoptotic processes in aged skeletal muscle of male rats JF - EXPERIMENTAL GERONTOLOGY J2 - EXP GERONTOL VL - 67 PY - 2015 SP - 9 EP - 14 PG - 6 SN - 0531-5565 DO - 10.1016/j.exger.2015.04.008 UR - https://m2.mtmt.hu/api/publication/2883904 ID - 2883904 AB - Abstract Aging results in significant loss of mass and function of the skeletal muscle, which negatively impacts the quality of life. In this study we investigated whether aerobic exercise training has the potential to alter anabolic and catabolic pathways in the skeletal muscle. Five and twenty eight month old rats were used in the study. Aging resulted in decreased levels of follistatin/mTOR/Akt/Erk activation and increased myostatin/Murf1/2, proteasome subunits, and protein ubiquitination levels. In addition, TNF-α, reactive oxygen species (ROS), p53, and Bax levels were increased while Bcl-2 levels were decreased in the skeletal muscle of aged rats. Six weeks of exercise training at 60% of VO2max reversed the age-associated activation of catabolic and apoptotic pathways and increased anabolic signaling. The results suggest that the age-associated loss of muscle mass and cachexia could be due to the orchestrated down-regulation of anabolic and up-regulation of catabolic and pro-apoptotic processes. These metabolic changes can be attenuated by exercise training. LA - English DB - MTMT ER - TY - JOUR AU - Padulo, J AU - Filingeri, D AU - Chamari, K AU - Migliaccio, GM AU - Calcagno, G AU - Bosco, G AU - Annino, G AU - Tihanyi, József AU - Pizzolato, F TI - Acute effects of whole-body vibration on running gait in marathon runners JF - JOURNAL OF SPORTS SCIENCES J2 - J SPORT SCI VL - 32 PY - 2014 IS - 12 SP - 1120 EP - 1126 PG - 7 SN - 0264-0414 DO - 10.1080/02640414.2014.889840 UR - https://m2.mtmt.hu/api/publication/2824867 ID - 2824867 AB - The aim of this study was to investigate the effects of a single bout of whole-body vibration (WBV) on running gait. The running kinematic of sixteen male marathon runners was assessed on a treadmill at iso-efficiency speed after 10 min of WBV and SHAM (i.e. no WBV) conditions. A high-speed camera (210 Hz) was used for the video analysis and heart rate (HR) was also monitored. The following parameters were investigated: step length (SL), flight time (FT), step frequency (SF), contact time (CT), HR and the internal work (WINT). Full-within one-way analysis of variance (ANOVA) of the randomised crossover design indicated that when compared to SHAM conditions, WBV decreased the SL and the FT by ~4% (P < 0.0001) and ~7.2% (P < 0.001), respectively, and increased the SF ~4% (P < 0.0001) while the CT was not changed. This effect occurred during the first minute of running: the SL decreased ~3.5% (P < 0.001) and SF increased ~3.3% (P < 0.001). During the second minute the SL decreased ~1.2% (P = 0.017) and the SF increased ~1.1% (P = 0.02). From the third minute onwards, there was a return to the pre-vibration condition. The WINT was increased by ~4% (P < 0.0001) during the WBV condition. Ten minutes of WBV produced a significant alteration of the running kinematics during the first minutes post exposure. These results provide insights on the effects of WBV on the central components controlling muscle function. LA - English DB - MTMT ER - TY - JOUR AU - Di Giminiani, R AU - Fabiani, L AU - Baldini, G AU - Cardelli, G AU - Giovannelli, A AU - Tihanyi, József TI - Hormonal and neuromuscular responses to mechanical vibration applied to upper extremity muscles JF - PLOS ONE J2 - PLOS ONE VL - 9 PY - 2014 IS - 11 SP - e111521 SN - 1932-6203 DO - 10.1371/journal.pone.0111521 UR - https://m2.mtmt.hu/api/publication/2824863 ID - 2824863 AB - OBJECTIVE: To investigate the acute residual hormonal and neuromuscular responses exhibited following a single session of mechanical vibration applied to the upper extremities among different acceleration loads. METHODS: Thirty male students were randomly assigned to a high vibration group (HVG), a low vibration group (LVG), or a control group (CG). A randomized double-blind, controlled-parallel study design was employed. The measurements and interventions were performed at the Laboratory of Biomechanics of the University of L'Aquila. The HVG and LVG participants were exposed to a series of 20 trials x10 s of synchronous whole-body vibration (WBV) with a 10-s pause between each trial and a 4-min pause after the first 10 trials. The CG participants assumed an isometric push-up position without WBV. The outcome measures were growth hormone (GH), testosterone, maximal voluntary isometric contraction during bench-press, maximal voluntary isometric contraction during handgrip, and electromyography root-mean-square (EMGrms) muscle activity (pectoralis major [PM], triceps brachii [TB], anterior deltoid [DE], and flexor carpi radialis [FCR]). RESULTS: The GH increased significantly over time only in the HVG (P = 0.003). Additionally, the testosterone levels changed significantly over time in the LVG (P = 0.011) and the HVG (P = 0.001). MVC during bench press decreased significantly in the LVG (P = 0.001) and the HVG (P = 0.002). In the HVG, the EMGrms decreased significantly in the TB (P = 0.006) muscle. In the LVG, the EMGrms decreased significantly in the DE (P = 0.009) and FCR (P = 0.006) muscles. CONCLUSION: Synchronous WBV acutely increased GH and testosterone serum concentrations and decreased the MVC and their respective maximal EMGrms activities, which indicated a possible central fatigue effect. Interestingly, only the GH response was dependent on the acceleration with respect to the subjects' responsiveness. LA - English DB - MTMT ER - TY - JOUR AU - Schuth, Gábor AU - Hegyi, A AU - Péter, A AU - Cronin, N AU - Tihanyi, József TI - Funkcionális és explozív térdhajlító-térdfeszítő arány 11-16 éves férfi labdarúgóknál JF - SPORTORVOSI SZEMLE J2 - SPORTORV SZLE VL - 55 PY - 2014 IS - 1 SP - 7 EP - 8 PG - 2 SN - 0209-682X UR - https://m2.mtmt.hu/api/publication/2597086 ID - 2597086 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Ureczky, Dóra AU - Vácz, Gabriella AU - Costa, A AU - Kopper, Bence AU - Lacza, Zsombor AU - Hortobágyi, Tibor AU - Tihanyi, József TI - The effects of short-term exercise training on peak-torque are time- and fiber-type dependent JF - JOURNAL OF STRENGTH AND CONDITIONING RESEARCH J2 - J STRENGTH CONDIT RES VL - 28 PY - 2014 IS - 8 SP - 2204 EP - 2213 PG - 10 SN - 1064-8011 DO - 10.1519/JSC.0000000000000414 UR - https://m2.mtmt.hu/api/publication/2565422 ID - 2565422 AB - We examined the susceptibility of fast and slow twitch muscle fibers in the quadriceps muscle to eccentric exercise induced muscle damage. Nine healthy males (age: 22.5+/-1.6 years) performed maximal eccentric quadriceps contractions at 120 degrees /s over a 120 degrees of knee joint range of motion for six consecutive days. Biopsies were taken from the vastus lateralis muscle before repeated bouts of eccentric exercise, on the third and seventh day. Immunohistochemical procedures were used to determine fibre composition and fibronectin activity. Creatine kinase (CK) and lactate dehydrogenise (LDH) were determined in serum. Average torque was calculated in each day for each subject. Relative to baseline, average torque decreased 37.4% till day 3 and increased 43.0% from the day 3 to day 6 (p<0.001). CK and LGH were 70.6 and 1.5 times higher on day 3 and 75.5 and 1.4 times higher on day 6. Fibronectin was found in fast fibres in subjects with high CK level on Day 3 and 7 after exercise, but on Day 7 fibronectin appeared in both slow and fast fibres except in muscles of two subjects with high fast fiber percentage. Peak torque and muscle fiber type composition measured at baseline showed a strong positive association on Day 3 (r = 0.76 p < 0.02) and strong negative association during recovery between Day 3 to Day 6 (r = -0.76, p < 0.02) and Day 1 to Day 6(r = 0.84 p < 0.001). We conclude that damage of fast fibers preceded the damage of slow fibers and muscles with slow fiber dominance were more susceptible to repeated bouts of eccentric exercise than fast fiber dominance muscles. The data suggest the responses to repeated bouts of eccentric exercise are fiber type-dependent in the quadriceps muscle which can be the basis for the design of individualized strength training protocols. LA - English DB - MTMT ER - TY - JOUR AU - Kopper, Bence AU - Csende, Zsolt AU - Trzaskoma, Lukasz AU - Tihanyi, József TI - Stretch-shortening cycle characteristics during vertical jumps carried out with small and large range of motion. JF - JOURNAL OF ELECTROMYOGRAPHY AND KINESIOLOGY J2 - J ELECTROMYOGR KINES VL - 24 PY - 2014 IS - 2 SP - 233 EP - 239 PG - 7 SN - 1050-6411 DO - 10.1016/j.jelekin.2014.01.001 UR - https://m2.mtmt.hu/api/publication/2530023 ID - 2530023 AB - In the present study we investigated kinematical characteristics of the knee and ankle extensors to estimate the length change properties of the contractile and the passive elements in countermovement jumps (CMJ) and drop jumps (DJ) performed with small (40 degrees ) and large (80 degrees ) range of joint motion (SRM and LRM). At SRM the accelerations at maximal muscle lengths compared with the last phase of joint flexion were greater for the gastrocnemius and the soleus (124.9% and 79.4%) and also were greater than at the beginning of joint extension, while no difference was measured at LRM. The differences suggest that at LRM the length change of the serial passive elements from the end of joint flexion to the beginning of joint extension is minimal and simultaneously the length change of the contractile elements is significant, but at SRM - especially in the plantar flexors - the length change of the contractile elements is minimal while in the passive elements significant. It can be presumed that for SRM at the end of joint flexion significant elastic energy is stored and at the beginning of joint extension reused, while for LRM elastic energy storage is not dominant. LA - English DB - MTMT ER - TY - JOUR AU - Biernat, R AU - Trzaskoma, Z AU - Trzaskoma, Lukasz AU - Czaprowski, D TI - Rehabilitation protocol for patellar tendinopathy applied amongst 16- to 19-year old volleyball players JF - JOURNAL OF STRENGTH AND CONDITIONING RESEARCH J2 - J STRENGTH CONDIT RES VL - 28 PY - 2014 IS - 1 SP - 43 EP - 52 PG - 10 SN - 1064-8011 DO - 10.1519/JSC.0b013e31829797b4 UR - https://m2.mtmt.hu/api/publication/2335033 ID - 2335033 LA - English DB - MTMT ER - TY - JOUR AU - Trzaskoma, Z AU - Trzaskoma, Lukasz AU - Krzesicka, A TI - Strength Training in elderly people JF - ADVANCES IN REHABILITATION J2 - ADV REHAB VL - 27 PY - 2013 IS - 1 SP - 49 EP - 61 PG - 13 SN - 0860-6161 DO - 10.2478/rehab-2014-0006 UR - https://m2.mtmt.hu/api/publication/2554107 ID - 2554107 LA - Polish DB - MTMT ER -