Background: Muscle activities of gluteus maximus (GM) and hamstring (HAM) have important roles in the stability and mobility of the hip joint during various functional activities including bridge and prone hip extension exercises. Objects:The purpose of this study is to investigate muscle activities of GM, multifidus (MF) and HAM during three different bridge exercises in healthy individuals.Methods: Twenty healthy subjects were participated. Electromyography device was used to measure muscle activities of GM, MF and HAM. Each subject was asked to perform three different bridge exercises with hip abduction (0°, 15°, 30°) in random order. One-way repeated measures analysis of the variance and a Bonferroni post hoc test were used. Statistical significance was set at α = 0.01. Results:The muscle activity of GM was significantly different among three conditions (hip abduction 0°, 15°, 30°) (adjusted p-value [Padj] < 0.01). The muscle activity of GM was significantly greater during bridge exercise with hip abduction 30° compared to 0° and 15° (Padj < 0.01). There was no significant difference in the muscle activity of MF and HAM muscle (Padj > 0.01). The ratio of muscle activity (ratio = GM/HAM) during bridge exercise with hip abduction 30° was significant greater compared to the hip abduction angles 0° and 15° (Padj < 0.01). Conclusion:Bridge exercise with hip abduction 30° can be recommended to selectively facilitate the muscle activity of GM and improve the ratio of muscle activity between GM and HAM.

Purpose: Ankle dorsiflexion is an essential element of normal functions, including walking, activities of daily living and sport activities. The tibialis anterior (TA) muscle functioned as a dorsiflexor and as a dynamic stabilizer of the ankle joint during walking and jumping. This study aimed to compare TA muscle thickness using ultrasonography according to the four different toe and ankle postures for the selective TA strengthening exercise. Methods: This study were recruited 26 (males: 15, females: 11) aged 20-30 years, with no injury ankle and calf in the medical history, had normal dorsiflexion and inversion range of motion (ROM). The thickness of the TA muscle was measured by ultrasonography in the four different toe and ankle postures: 1. Ankle dorsiflexion with all toe extension and ankle inversion (ITEDF); 2. Ankle dorsiflexion with all toe flexion and ankle inversion (ITFDF); 3. Ankle dorsiflexion with all toe extension and neutral position (NTEDF); 4. Ankle dorsiflexion with all toe flexion and neutral position (NTFDF). One-way repeated analysis of variance (ANOVA) and Bonferroni correction were used to confirm the significant difference among conditions. The level of statistical significance was set at α= 0.01. Results: TA muscle thickness with ITFDF was significantly greater than in any other ankle positions, including ITEDF, NTFDF, and NTEDF (p< 0.01). Conclusion: Among the four toe and ankle postures, isometric contraction in ITFDF postures showed the greatest increase in thickness of TA rather than ITEDF, NTEDF, and NTFDF postures. Based on these results, ITFDF can be recommended in an efficient way to selectively strengthen TA muscle.

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons. org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Purpose The purpose of this study was to compare muscle activity of SA during three different scapular protraction exercises according to various conditions [Forward flexion with protraction (FFP), FFP with self-resistance (FFPS), FFPS with hand-exerciser (FFPSH)] in healthy individuals in sitting position. Study design Comparative, repeated measures designMethods Twenty subjects were participated. The muscle activity of SA, upper trapezius (UT) and pectoralis major (PM) were measured by using a surface electromyography device. Each subject was asked to perform three different scapular protraction exercises (FFP vs. FFPS vs. FFPSH) in random order. One-way repeated measures analysis of the variance and a Bonferroni post hoc test were used. The level of statistical significance was set at α=0.01. ResultsThe muscle activity of SA and the SA/UT ratio were significantly different among three conditions (FFP vs. FFPS vs. FFPSH) (p<0.01). The muscle activity of SA and the SA/UT ratio during FFPSH were significantly greater compared to those with FFP and FFPS (p<0.01). However, the SA/PM ratio was not significantly different among three conditions (p>0.05).Conclusions FFPSH exercise for facilitation of SA muscle can be recommended.

Purpose: This study investigated the muscle activity of the lower trapezius (LT) during three different shoulder flexion exercises. Methods: Twenty-three subjects between 20 and 25 years of age were enrolled. The subjects were asked to perform three different shoulder flexion exercises: 1) shoulder flexion in prone (SFP), 2) shoulder flexion in push-up with a swiss ball (SFPUS) and 3) shoulder flexion in a quadruped position with a swiss ball (SFQPS) in random order. The muscle activity of LT during each shoulder flexion exercise was measured by using surface electromyography. The muscle activity of LT was compared using one-way analysis of variance (ANOVA) and Bonferroni post hoc test among three different shoulder flexion exercises. The statistical significance level was set at α= 0.01. Results:The muscle activity of LT was significantly different among three different shoulder flexion exercises (SFP, SFPUS, and SFQPS). The LT muscle activity with SFQPS exercise was greater than SFP and SFPUS exercises (p< 0.01). There was no significant difference in LT muscle activity between SFP and SFPUS exercises (p> 0.01). Conclusion:The LT muscle activity was greater during SFQPS than SFP and SFPUS. Therefore, SFQPS exercise can be recommended for selectively activation of LT muscle.

The purpose of the current study was to determine the intra-and inter-rater reliability of muscle thickness measurement of the TA using ultrasonography (US) conducted at different inward pressures of approximately 0.5 kg, 1.0 kg, and no pressure control. Methods: Twenty healthy subjects were recruited for this study. Two different examiners measured the thicknesses of the dominant TA of each subject randomly to assess the intra-and inter-rater reliability. The measurement values were analyzed using the intra-class correlation coefficient (ICC) with a 95% confidence interval, standard error of measurement, minimal detectable change, and coefficient of variance. Results: All intra-rater reliability ICC values showed high reliability above 0.9. Inter-rater reliability ICC values showed high reliability above 0.9 with 0.5 and 1.0 kg of inward pressure. In contrast, Inter-rater reliability ICC values showed poor reliability (0.23) with no pressure control of inward pressure. Conclusion:The findings showed that maintaining consistent inward pressure is essential for reliable results when the muscle thickness of the TA is measured by different examiners in a clinical setting.