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Introduction: Asymmetrical gait mechanics after anterior cruciate ligament reconstruction (ACLR) are associated with the development of post-traumatic knee osteoarthritis. Current measures of gait mechanics have focused on peak magnitudes of knee kinematics, kinetics, and joint contact forces; nonetheless, they have seldom considered the plantar pressure and muscular frequency content in individuals with ACLR and pronate feet (PF). The present study aimed to compare ACLR and PF with healthy controls during walking. Material & Methods: The present study was conducted based on a quasi-experimental and laboratory design. The sample of this study comprised 13 people with ACLR and PF and 13 subjects from the healthy group. The mean age scores of patients in the two groups of healthy and sick participants were 22.9±4.1 and 23.2±4.5 years, respectively. During the test, subjects walked barefoot on an 18-m runway. Peak plantar pressure variables in both groups were recorded by a foot scan system (sampling rate: 300 Hz). The electromyography activity of the tibialis anterior, gastrocnemius medialis, vastus lateralis, vastus medialis, rectus femoris, biceps femoris, semitendinosus, and gluteus medius were recorded during walking. Results:The results demonstrated that the peak midfoot region plantar pressure values (P=0.018) were higher in the ACLR/PF group than in the healthy group during walking. In addition, the results highlighted a significant difference in the muscle frequency content of the rectus femoris (P=0.012, d=0.68) and vastus latelarlis (P=0.042) during the loading response and push-off phase in the ACLR/PF group compared to the healthy group during walking. Discussion & Conclusion: Peak plantar pressure values at the midfoot region and rectus femoris and vastus lateralis muscular frequency content in the ACLR/PF group differed from that of the healthy group during walking. [ABSTRACT FROM AUTHOR]

Background Exercise and physical activity improve damage and destructive changes in the peripheral nervous system. Objective This study aims to investigate the effects of resistance aerobic training on the expression of SEMA3A and NCAM genes and proteins of soleus muscle in male rats of different age groups. Methods A total of 30 male Wistar rats in three groups of 2-week-old (infant) (n=10), 6-week-old (young) (n=10), and 96-week-old (elderly) (n=10) were divided into two groups of training and control. The training program included 6 days of resistance and aerobic training one day in between. The rats were euthanized and the soleus muscle was extracted 48 h after the last training session. A fluorescent microscope was used to measure SEMA3A and NCAM proteins in muscle fibers. Gene expressions were measured by real-time polymerase chain reaction. Results The results showed that SEMA3A gene expression was not significantly different between exercise and control groups in all three age groups; however, SEMA3A protein expression was significantly reduced in infant and young exercise groups (P≤0.001). Also, NCAM gene expression was not significantly different between training and control groups in all three age groups; while there was a significant decrease in NCAM protein expression in young and old training groups compared to the control group (P≤0.001). Conclusion The results showed that resistance aerobic training can inhibit the process of peripheral nerve damage in infant and young rats, as well as the growth and strength of the neuromuscular junction in young and elderly rats. [ABSTRACT FROM AUTHOR]

Background and Aim Several microRNAs are involved in regulating muscle mass, which plays an essential role in hypertrophy and atrophy of skeletal muscle, The present study examined the expression of some genes as regulators of muscular atrophy following a period of inertia in rats. Methods & Materials For this purpose, 18 male Sprague-Dawley rats were divided into three groups (Control, Exercise+inactivity, and Inactivity). The exercise+inactivity group run on the treadmill for 18 weeks and five times per week. The hindlimb of the animal was immobilized for seven days with the casting method. Soleus muscle was extracted and the expression of the genes was measured by the RT-PCR method. Univariate ANOVA and Tukey post hoc test was used to determine the differences (α=0.05). Ethical Considerations The Ethics Committee of the Tehran University of Medical Sciences Research approved this study (Code: IR.SUMS.REC.1396.S 463). Results Results showed that immobilization in both Exercise+ inactivity and inactivity groups, compare to the control group, increased expression of miR-1 genes (P<0.10), FOXO3a (P<0.001) and decreased expression of miR-206 (P<0.007) and IGF-1 (P<0.001). This difference was statistically significant. Conclusion According to the results of this study, it can be said that changes in the expression of RNAs by chromatography cause changes in the expression of muscle regulating genes, and although endurance exercises have protective effects, they cannot prevent these changes. [ABSTRACT FROM AUTHOR]

Background and Objective: Trophic factor family plays a key role for neuromuscular system healthy. This study was carried out to determine the effect of one session of resistance exercise on protein content and mRNA expression of NT4/5 in rat slow and fast muscles. Methods: In this experimental study, sixteen adult male rats randomly were allocated into resistance exercise (T) and control groups. The resistance training protocol consisted of climbing a 1-meter-long ladder, with a weight attached to a tail sleeve. Quantitative Real time RT-PCR for NT-4/5 expression and ELISA Kit for protein assay were used. Results: Resistance training significantly decreased mRNA expression and increased protein of NT4/5 in soleus muscle (P<0.05). Significant alteration was not detected in flexor hallucis longus muscle. Conclusion: One session of resistance training can alter protein and mRNA of NT-4/5 in skeletal muscle and this alteration was dependent on muscle type. [ABSTRACT FROM AUTHOR]