Effects of power training on muscle structure and neuromuscular performance

Abstract

The present study examines changes in muscle structure and neuromuscular performance induced by 15 weeks of power training with explosive muscle actions. Twenty‐three subjects, including 10 controls, volunteered for the study. Muscle biopsies were obtained from the gastrocnemius muscle before and after the training period, while maximal voluntary isometric contractions (MVC) and drop jump tests were performed once every fifth week. No statistically significant improvements in MVC of the knee extensor (KE) and plantarflexor muscles were observed during the training period. However, the maximal rate of force development (RFD) of KE increased from 18 836±4282 to 25 443±8897 N (P<0.05) during the first 10 weeks of training. In addition, vertical jump height (vertical rise of the center of body mass) in the drop jump test increased significantly (P<0.01). Simultaneously, explosive force production of KE muscles measured as knee moment and power increased significantly; however, there was no significant change (P>0.05) in muscle activity (electromyography) of KE. The mean percentage for myosin heavy chain and titin isoforms, muscle fiber‐type distributions and areas were unchanged. The enhanced performance in jumping as a result of power training can be explained, in part, by some modification in the joint control strategy and/or increased RFD capabilities of the KE.

Elbow Joint Position Sense After Neuromuscular Training With Handheld Vibration

“…[20][21][22][23][24][25][26] The precise mechanisms behind such acute adaptations remain largely unknown; however, researchers have postulated they are similar to the enhanced neuromuscular efficiency observed over the initial 10 weeks of power training. 23,39 Although our JPS measure assessed function of the neuromuscular components proposed to act more efficiently, it is not clear if the enhanced position sense we observed was a result of a similar mechanism. Further investigation is needed to identify whether vibration may enhance SMS function by improving efficiency of the transmission, processing, or integration of afferent or efferent signals.…”

Neuromuscular mechanics and hopping training in elderly

“…Lack of tendon adaptation after plyometric training as compared to that after strength training may suggest that in addition to high loading magnitude, a high loading duration per contraction is required for tendon adaptation, as suggested also by Arampatzis et al (2010) and Kubo et al (2001). In addition, it can be argued that since tendon stiffness is closely related to strength level , calf muscle strength may not have changed much with hopping training (Kyrolainen et al 2005;Piirainen et al 2014) and therefore also the stiffness remains unchanged. On the other hand, it must be noted here that the GaM outer tendon was measured in the present study, whereas most of the studies have measured the combined stiffness of the tendon-aponeurosis structure (e.g.…”

Vitamin B12 Eksikligine Bagli Subakut Kombine Dejenerasyon: Bir Olgu Nedeniyle Gozden Gecirme

“…İntramedüller lezyonu olan olguların ayırıcı tanısında; demiyelinizan hastalıklar, infeksiyöz nedenler, inflamatuvar hastalıklar, neoplazmlar, Vitamin E eksikliği gibi metabolik hastalıklar, karsinömatöz radikülopati, arteriyel veya venöz iskemiler, radyasyon miyeliti yer almaktadır (17,27,28). Demiyelizan hastalıklarda lezyon genellikle iki vertebra aralığını geçmez ve postero-lateral yerleşimli olurken, SKD'deki lezyonlar sıklıkla arka kolumnada görüldüğü ve birkaç vertebra bölümünde uzanabildiği bilinmektedir (29)(30)(31)(32). Olgumuzda kranial MRG'nin normal olması, spinal lezyonun 2 vertebra aralığından uzun olması, semptomatik olmasına rağmen kontrastlanmaması, BOS OKB'ın (-) ve IgG indeksinin normal sınırlarda olması nedeni ile MS tanısından uzaklaşılmıştır.…”