Earticle

Purpose: This study aimed to compare the effects of lower muscle strengthening and balance when vibration foam roll and flossing band exercises were performed for 4 weeks by the elderly. Methods: Twenty elderly participants, aged ≥ 65 years, were selected for this study. The participants were equally divided into two groups. Group A performed vibrating foam roll exercises. Group B performed flossing band exercises. Each group performed the respective exercises two times per week for 4 weeks and underwent measurements during muscle strength and timed up-and-go tests. Data were analyzed using SPSS 21.0. An independent t test was used to determine the statistical differences between the groups, and a paired t-test was used to determine statistical differences within the groups. Statistical significance was determined at α =.05. Results: Both the vibration foam roll and flossing band exercise groups showed significant changes in muscle strength and balance in the knee flexors and extensors, ankle dorsi flexors, and ankle plantar flexors between the pre and post intervention values (p＜.05). However, we found no significant differences between the two groups except for the knee extensor. Conclusion: In this study, both the vibrating foam roll and flossing band exercises were effective for improving various measures regarding muscle strength and balance.

Purpose: This study aimed to investigate the effect of transcranial direct current stimulation (tDCS) on the onset of upper extremity muscle activities during forward reaching performance. Methods: Fifteen healthy men (age, 24.2±1.55y) participated in this randomized double-blind crossover study. Each participant received both a sham and 2-mA stimulation over M1 bilaterally for 20 min, with a minimum washout period of 4 days. Muscle activation was evaluated for all the participants during the task of reaching out for a marked target as fast as possible, using electromyography (EMG) before and immediately after tDCS application. Results: For the within arm-length reaching performance in the 2-mA stimulation session, the muscle activities of the anterior deltoid (AD), posterior deltoid (PD), biceps brachii (BB), and inferior spinatus (IS) were decreased significantly during, immediately after, and 20 min after the tDCS period compared with the baseline values (p for all values ＜0.05). The pectoralis major (Pec) muscle showed a significant decrease only in the 20-min period after tDCS compared with the baseline values (p=0.001). For the beyond arm-length reaching performance, the 2-mA application on the AD, PD, BB, and IS showed significant decreases in onset time in all the periods after tDCS as compared with the baseline (p for all values ＜0.05). The onset of the triceps brachii muscle activity significantly decreased immediately and 20 min after the tDCS periods. For the Pec muscle, the onset time of muscle activation significantly changed only in the 20 min after the tDCS period compared with the baseline values. Conclusion: The present study demonstrated that bilateral tDCS over M1 facilitates muscle activation rapidly during the reaching performance, regardless of the reaching target distance.

Purpose: This study aimed to analyze motion variability according to the target height during roundhouse kick. Methods: Twelve male adults aged 22.9±1.6 years without Taekwondo training participated in this study. Eight motion analysis cameras and optical markers were used. The height of the target was set to 60% (waist) and 85% (head) of the height of the participant. The distance was set using the leg length. Experiments were performed using visual stimulation, and the roundhouse kick motion was performed 12 times in each round. For data analysis, we divided the motion into four events as follows: start, heel-off, toe-off, and impact. The knee joints, hip, pelvis, and trunk of the dominant and non-dominant legs were measured. The coefficient of variation (CV) was used to quantify the variability. Results: The CV of the waist-height target in the dominant-leg knee was greater in the start and impact events. In the heel-off and toe-off phases, the CV of the head-height target was greater. The non-dominant-leg knee joints had greater head-to-head CV in all the events except the impact events. The CV of the waist-height target was greater in the dominant-leg hip at all the stages except the start event. The non-dominant-leg hip showed a greater CV of the waist-height target at all events. In the pelvis, the CV of the waist-height target was greater in the start and impact events, and the CV of the head-height target was greater in the heel-off and toe-off stages. The trunk had greater CV of the head-height target at all steps except at toe-off. Conclusion: Injured persons have high variability. Variability measurements can be used to observe the relationship with the musculoskeletal system. The variability of movement should be analyzed not only for the taekwondo kick motion but also for various sport motions.

Purpose: This study aimed to evaluate the existing studies on injury prevention strategies for elite athletes who participate in major international sports competitions and to examine the comprehensive core strategic factors. Methods: Through preparation for international sporting events and an analysis of injuries and illnesses through a detailed literature review, the foundation of the injury prevention strategy for elite athletes preparing for international sporting events was established. From the perspective of sports physical therapists, we aimed to create an injury prevention plan. Results: The results of this study are as follows: 1) conditioning strategy, 2) sports injury surveillance, 3) factual survey of illnesses and injuries, 4) medical care delivery service and physical therapy, 6) injury prevention program, and 7) illness prevention strategies. On the basis of the characteristics of each event and its environment, an optimal strategy for injury prevention is needed. Conclusion: In addition to this research, research on sports physiotherapy should be continued to maintain the best condition of domestic athletes through prevention of injuries at the time of the 2019 Gwangju World Swimming Championships and 2020 Tokyo Olympics.

Purpose: This study aimed to evaluate the effect of task-oriented training on trunk stabilization, coordination of the lower extremities, and dynamic balance of patients with stroke. Methods: Ten patients with stroke were randomly divided into two groups of five patients each who met the selection criteria. The training was conducted five times a week for 60 minutes. The experimental group received task-oriented training and general physical therapy, while the control group received only general physical therapy. The Mann-Whitney U test was used to compare differences between the groups, and the Wilcoxon signed-rank test was used to compare differences between pre- and post-intervention within each group. Results: Trunk stabilization was measured using the trunk impairment scale. Only the coordination assessment on the trunk impairment scale was statistically significant after intervention in the experimental group (p = 0.046) and between the experimental and control groups (p = 0.029). The LEMOCT, figure-of-8 walk test (F8WT), timed up-and-go (TUG) test results were not statistically significantly different in the group after intervention. However, the F8WT and TUG test results showed a statistically significant difference between the experimental and control groups (p = 0.029). Conclusion: The task-oriented training showed positive effects on the trunk stabilization, coordination of the lower extremities, and dynamic balance of the patients with stroke.

Purpose: This study aimed to investigate the effect of ergometer exercise after performing static stretching and strength exercise on the activity of the quadriceps muscle. In general, the effects of performing both the strength and stretching exercises before ergometer exercises were examined. Methods: The participants were divided into two exercise groups and performed static stretching and strength exercises and then ergometer exercise. Each exercise was performed for 4 weeks, three times a week, by each group to measure changes in the muscle activities of the rectus femoris, vastus lateralis, and vastus medialis. Measurements were made at weeks 0 and 4, and electromyography was used in a static posture. Results: Both the stretching and strength exercise groups showed significant increases in the rectus femoris, vastus lateralis, vastus medialis muscle activities after exercise. Conclusion: Stretching and strength exercises before ergometer exercise helps to increase muscle activities. Stretching is thought to be more effective for gaining muscle activity than muscle strength. However, no significant difference was found between the two groups.

Purpose: This study investigated the effects of the newly-developed high-frequency stimulation over knee on physiological characteristics of quadriceps (QM) and hamstring (HM) muscles. Methods: Ten healthy participants were participated in the study (average age: 49.3). Each participant received the high-frequency stimulation over both knees over three times a week during a total of two weeks. We measured the physiological characteristics of muscle tissue of QM and HM, including muscle tone (F), dynamic stiffness (S), and elasticity (D) by a Myoton device at pre and post-stimulation. Results: As a result, the elasticity of right HM was showed significant differences between pre- and post-stimulation (P=0.006). Conclusion: We conclude that the high-frequency stimulation over both knee may evoke the physiological changes in knee muscles.