Physical movement is reduced because of convinient life style by advancing of science. People need physical movement and athletes also need more physical training for their health and better records because of reduced movement in modern life style. Some athletes competing in contact sports wear dental mouth guards to reduce the risk of orofacial trauma and to increase the strength of muscle. It has been speculated that the use of mouth guards improves athletic ability such as muscular strength and equilibrium. The purpose of this study was to test the influence of C.M(custom made) mouth guard according to strength of taekwondo athletes. 5 trained subjects participating in taekwondo students in D University were included in this study. Deltoid muscular activity were tested by means of electromyograph (E.M.G) with or without wearing mouth guard. Subjects have pressed with 5 Kg barbell. The data were transferred to computer system as raw and integral data. The data were analysed by computer system, showing wearing mouth guard had higher action potential than non-wearing mouth guard. This meant that wereing mouth guard could enhance the muscle force in deltoid. It suggested that taekwondo athletes could use C.M mouth guard without any negative effect on their muscle strength.

The purpose of this study was to suppose basis data the influence of different chair type and pelvic control on quadriceps muscle activity and strength during knee joint extension isometric exercise in hemiplegic patients. This research were investigated in ten healthy adults and tens hemipelgic patients. Surface electromyography (EMG) and Biodex system were used to collect kinematic data and muscle activity, respectively. Independent t-test, paired t-test and one-way repeated ANOVA were used to determine a statistical significance. The results showed as follows: (1) Posterior pelvic angles in healthy group and hemiplegic group were significantly different on isokinetic equipment (p<.05). (2) Different chair type and pelvic control on quadriceps muscle activity and strength were significantly different in hemiplegic patients (p<.05). From the result of this research, posterior pelvic angle control during knee joint extension isometric exercise in hemiplegic patients on isokinetic equipment is necessary to increase quadriceps muscle strength in hemiplegic patients.

The quadriceps-angle (Q-angle) and the ratio of hamstring/quadriceps (H/Q) are important for the stability of the knee and for protection from excessive stress. The aim of this study was to examine the association between Q-angle and H/Q ratio with and without knee osteoarthritis. We compared knee osteoarthritis patients with symptom-free women. The mean age of the patients in the arthritis group (25 women, osteoarthritis) was 59.7 years. The non-arthritis group consisted of 25 women with a mean age of 55.2 years. Of the 25 women with osteoarthritis, 5 had the condition in their left knee, 5 had it in their right knee, and 15 had it on both sides. There was no significant difference in the knee Q-angle of the left and right knees of the arthritis group and the non-arthritis-group (p>.05). The strength of all the muscles around the involved right knee in the arthritis group was significantly weaker than that of the non-arthritis group (p<.05). However, in the left knee, only the strength of the knee extensors and internal rotators was significantly weaker than that of the non-arthritis group (p<.05). The Q-angle was not associated with the H/Q ratio and internal rotators/external rotators ratio of the involved knee in the arthritis group (p>.05). Neither was the Q-angle associated with the pain level of an involved knee in the arthritis group (p>.05). The knee pain was not associated with the H/Q ratio of the involved knee in the arthritis group (p>.05). The Q-angle was not associated with the ratio of H/Q and pain level of the involved knee in the osteoarthritis women.

This study was designed to develop an objective method of strength measurement of muscles controlling the wrist joint in normal subjects. Forty subjects (20 male, 20 female) with a mean age of 22 years, were tested isokinetically at and . Results were as follows, 1) Peak torque for wrist flexors, extensors were significantly different for both speeds, but wrist ulnar deviator, radial deviator peak torques were not, 2) Mean values for all muscle groups controlling the wrist were not significantly different for both speeds in the female group, 3) All mean values at both and were significantly different between males and females, 4) Means and standard deviations of wrist joint angle of movement at peak torque were determined.

Muscle strength and endurance activities of Korean ginseng (Panax ginseng C. A. Meyer; KG) were compared with those of wild simulated cultivation ginseng (WCG) in mice. Fifty male ICR mice were divided into five groups: A (vehicle); B (WCG 100 mg/kg); C (WCG 500 mg/kg); D (KG 100 mg/kg); E (KG 500 mg/kg). Subsequently, the mice were subjected to the forced swimming test (FST) and treadmill test at the 4th and 7th weeks. The glycogen content in the muscle and blood analysis (levels of glucose, triglyceride (TG), IGF-1) were also performed immediately after the last FST and treadmill test at the 7th week. Immobility times in FST were shorter in WCG- than KG-treated groups, and the results of the treadmill tests were also significant except for KG-treated at 100 mg/kg. The glycogen content was increased in both groups with a peak at 500 mg/kg of WCG groups. Serum concentrations of TG and glucose were decreased by administration of KG and WCG and all treated groups showed increase in the level of IGF-1 in serum. These results suggest that KG and WCG supplementations are effective in escalating the muscle strength and endurance.