Javad Nemati; Mahdi Samadi; Vahid Hadidi; Leila Ghodrat
Abstract
Background and Aim: To date, more than 100 types of kinases have been known that one of the most famous of them is the large family of mitochondria -cased kinases (MAPK), which regulated by the out-cell message (ERK). The ERK controls many important cellular functions, but the effect of resistance ...
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Background and Aim: To date, more than 100 types of kinases have been known that one of the most famous of them is the large family of mitochondria -cased kinases (MAPK), which regulated by the out-cell message (ERK). The ERK controls many important cellular functions, but the effect of resistance training on ERK protein has not been clearly revealed. The aim of this study was to investigate the effect of resistance training on the expression of total and phosphorylated ERK proteins in the flexor hallucis longus muscle (FHL) in healthy male rats. Materials and Methods: For this purpose, 12 male Sprague Dawley rats were randomly divided into groups as experimental (n=6) and control (n=6). The experimental groups exerted resistance training including climbing on a ladder during the 8 weeks, 5 sessions per week with a weight hanging on to the tail carried out increased load has been done weekly based on body weight of mice so that the first week was from 30% to 200% in 8 weeks. Fourty eight hours after the last training session, FHL muscle was extracted and the expression of the relevant protein was measured by ELISA. For statistical analysis, one-way ANOVA method was used with a significance level of 0.05. Results: The results showed that resistance exercise significantly increased the total protein content (p=0.01) but had no significantly increased its phosphorylated form (p=0.08). Conclusion: Probably, long-term resistance training is not an appropriate intervention to ERK activation. In order to investigate this exercise induced changes, perhaps it is better to examine other signalling pathways.
farzaneh movaseghi; Heydar Sadeghi; Sobhan Sobhani; Javad Nemati
Abstract
Background and Aim: Eccentric muscle action has more mechanically efficiency, predisposes the muscle to damage due to unique activation strategy. Postural control also is necessarily required for many daily and sport activities. The purpose of this study was to investigate the effect of high velocity ...
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Background and Aim: Eccentric muscle action has more mechanically efficiency, predisposes the muscle to damage due to unique activation strategy. Postural control also is necessarily required for many daily and sport activities. The purpose of this study was to investigate the effect of high velocity acute eccentric exercise-induced muscle damage of dominant knee extensors on muscle damage indices and postural control in trained young females. Materials and methods: Ten young trained females (21.9±1.66 years) voluntarily participated in this study. To analyse muscle damage, subjects performed 300 (20 sets, 15 repetitions) high velocity (240°.s-1) eccentric contractions of dominant knee extensors with a load equal to 150٪ of the maximal voluntary isometric torque (MVC).Muscle damage indices (MVC, perceived pain, thigh circumference) and center of pressure distance and velocity in the antero/posterior (AP) and the medio/lateral (ML) planes of movement were recorded before, 1 and 48 h after eccentric exercise. Statistical analysis was performed with SPSS (version 16.0), and the repeated-measures ANOVA test also were used. Results: All muscle damage indicators changed significantly (p<0.05) following eccentric exercise thats confirmed muscle damage. In contrast, no significant differences was observed for center of pressure distance and velocity in the AP and ML directions between all measured time points (p>0.05). Conclusion: In conclusion, the results of the present study showed that high velocity eccentric exercise that designed to elicit localized muscle damage of dominant knee extensors did not influence postural control during one-legged stance in trained young female.
