• Journal of Korean Clinical Health Science
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• v.5 no.4
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• pp.991-997
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• 2017

Purpose. The purpose of this study was to muscle properties analysis of SCM(sternocleidomastoid) Muscle according to posture type when using smartphone. Methods. This study was conducted on 73 college students who are using smartphone. Subjects were analyzed myotonPRO to confirm, prone posture group, stand posture group, drop head above $45^{\circ}$in sit posture on a chair group and drop head below $45^{\circ}$in sit posture on a chair group were measured SCM muscle. The myotonPRO were measured one measurer, total 3 times. Comparative analysis of the each groups were investigated of SCM muscle properties. Results. We found that Frequency, Stiffness, Creep and Relaxation were appeared difference in each posture. F index was increased at drop head below $45^{\circ}$group than stand posture group. S index was increased at drop head above $45^{\circ}$group than prone posture group. C index was decreased at drop head below $45^{\circ}$group and drop head above $45^{\circ}$group than prone posture group. R index was decreased at drop head above $45^{\circ}$group than prone posture group. Conclusions. The muscle properties were appeared difference in each posture of SCM muscle using smartphone.

• Korean Journal of Poultry Science
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• v.51 no.2
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• pp.97-106
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• 2024

This study utilized the non-invasive MyotonPRO^® device to analyze the stiffness in breast muscles of commercial broilers (Ross 308 and Arbor Acres) and compared these findings with data reported for Ross 708, where Woody Breast (WB) symptoms had been previously documented. The research revealed that Ross 308 and Arbor Acres displayed relatively lower stiffness values compared to Ross 708, suggesting a lack of WB expression. These results indicate differentiation in breast muscle traits across strains and underscore the necessity for further research into factors influencing WB manifestation. The study also measured additional muscle tone characteristics such as Frequency, Decrement, Relaxation, and Creep across various growth stages (2, 4, 6, and 8 weeks), finding significant variations with pronounced severity at weeks 2 and 8. An increase in stiffness was observed as the broilers aged, pointing to potential growth-related or stress-induced changes affecting WB severity. A strong positive correlation was established between increased breast meat weight and WB severity, highlighting that heavier breast meat could exacerbate the condition. This correlation is vital for the poultry industry, suggesting that weight management could help mitigate WB effects. Moreover, the potential for genetic selection and breeding strategies to reduce WB occurrence was emphasized, which could aid in enhancing management practices in commercial poultry production. Collectively, these insights contribute to a deeper understanding of WB in broilers and propose avenues for future research and practical strategies to minimize its impact.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.446-453
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• 2022

Objective: The popularization of smartphones can lead to abnormal cervical alignment in university students. The aim of this study was to investigate the relationship among smartphone screen time, cervical alignment, and muscle function in university students. Design: Cross-sectional study. Methods: Seventy-five university students participated in the study. They completed the evaluation of cervical alignment and muscle function, such as handgrip strength, proprioception, and muscle quality (tone, stiffness, and relaxation time). All participants recorded their general characteristics and individual smartphone screen time before the evaluation. They were evaluated craniovertebral angle (CVA) using smartphone application (angle meter 360) for measuring cervical alignment. The muscle function was assessed using a digital hand-held dynamometer, dual inclinometer, and MyotonPRO device. Results: Of all participants, twenty-five university students had forward head posture (CVA<49°, 33.33%). Independent t-test revealed that there were significant differences on smartphone screen time, muscle stiffness, and muscle relaxation between the participants with and without forward head posture (p<0.05). There were significant correlations between the smartphone screen time and the CVA, muscle tone, and muscle relaxation (r=-0.493, 0.250, and -0.500, respectively). Conclusions: The results indicate that the university students with forward head posture had high smartphone screen time and muscle stiffness compared to the students without forward head posture, and smartphone screen time might be associated with cervical alignment and muscle quality.

• Korean Journal of Applied Biomechanics
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• v.33 no.3
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• pp.101-109
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• 2023

Objective: The aim of this study is to verify the differences in muscle characteristics of elite level swimmers before and after a 2-hour practice session. Method: The study was conducted on 15 elite swimmers. Preliminary measurements for each muscle (Anterior Deltoid, Triceps Brachii, Biceps Brachii, Flexor Carpi Ulnaris) were taken using the MyotonPRO device before training. After approximately 2 hours of training, the same muscle areas were measured again. The collected data was analyzed through descriptive statistics and two-way 2×2 RG·RM ANOVA, and all statistical significance levels were set at α=.05. Results: After analyzing the characteristics of the Flexor Carpi Ulnaris (FCU) before and after training in both proficiency level swimmers (excellent, non-excellent), it was found that the interaction effect of group X repetition in muscle tension (F), muscle stiffness (S), and body recovery time (R) was statistically significant. Secondly, in the analysis of the Biceps Brachii (BB), the main effect of repetition in muscle tension (F), muscle stiffness (S), and body recovery time (R) was statistically significant. Furthermore, the interaction effect of group X repetition in muscle stiffness (S) and body recovery time (R) was statistically significant. Conclusion: The efficient use of FCU and BB suggests that it is an important factor distinguishing the performance of excellent and non-excellent swimmers in swimming. Therefore, if we develop and apply measures to efficiently utilize FCU and BB during training, it can help improve the performance of the athletes.

• Physical Therapy Korea
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• v.25 no.2
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• pp.13-21
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• 2018

Background: After a stroke, the patient may have abnormal muscle tone due to abnormal alignment. Physical therapists have used stretching, neural mobilization other methods to treat patients after stroke. In addition, joint mobilization is also used to stimulation in pathway of cervical segmental region and to normal cervical spine alignment. Objects: The purpose of this study was to determine whether Maitland cervical spine mobilization has an immediate effect on muscle tone and stiffness of upper extremity. Methods: Thirty subjects were divided into a experimental group ($n_1=10$), a placebo group ($n_2=10$), and a control group ($n_3=10$). The Maitland cervical spine mobilization was applied in the supine position. Immediately after the intervention, muscle tone and stiffness of biceps brachii, brachioradialis, deltoid, and pectoralis major were measured using Myoton(R)PRO. In the placebo group, sham mobilization was applied to the fifth and sixth cervical vertebra, and the control group was instructed to control breathing. Results: In the experimental group, significant differences were found in muscle tone and stiffness of biceps brachii and brachioradialis in comparison with the affected side and the non-affected side before the intervention (p<.05), whereas there was no significant difference after the intervention (p>.05). Muscle tone of biceps brachii on the non-affected side and pectoralis major on the affected side was significantly decreased before and after the intervention (p<.05). The placebo and control group showed no changes on the non-affected and affected side, and no significant differences were detected before and after the intervention. All the groups revealed no significant differences in muscle tone and stiffness of upper extremity before and after the intervention. Conclusion: This study suggests that the application of Maitland cervical spine mobilization enhanced muscle tone of upper extremity on the involved side symmetrically, and influenced a decrease in muscle tone.