Background:Individuals with spinal cord injury (SCI) rely on their upper limbs for body-lifting activity (BLA). While studies have examined the electromyography (EMG) and kinematics of the shoulder joints during BLA, no studies have considered foot position during BLA.Objects:This study compared the effects of different foot positions during BLA on the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion in individuals with SCI.Methods:The study enrolled 13 mens with motor-complete paraplegic SCI, ASIA (American Spinal Injury Association) A or B. All subjects performed BLA with the feet positioned on the wheelchair footrest and on the floor independently. Surface EMG was used to collect data from the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii. The peak plantar pressure was measured using pedar-X and the knee flexion angle with Image J. Borg’s rating perceived exertion scale was used to measure the physical activity intensity level. The paired t-test was used to compare the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion between the two feet positions during BLA.Results:The activity of the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii and rating perceived exertion decreased significantly and the peak plantar pressure and knee flexion angle increased significantly when performing BLA with the feet positioned on the wheelchair footrest compared with on the floor (p<.05).Conclusion:These findings suggest that individuals with SCI may perform BLA with the feet positioned on the wheelchair footrest for weight-relief lifting to decrease the shoulder muscle activities and the rating perceived exertion and to increase the peak plantar pressure and the knee flexion angle.

The difficulties in opening and closing a sport utility vehicle (SUV) tailgate is important aspect of JD (James David) power’s Initial Quality Survey (IQS) assessment, and affective quality has a big impact on the the success of thesedays products. The purpose of this study is to evaluate the perceived difficulty and satisfaction of customers by the opening and closing of the tailgate and to grasp the relationship between them and the opening and closing reaction force. The mechanical force required to open and close 42 domestic and overseas SUV tailgates was measured with the help of an auto company. In the experiment, 100 male drivers in their 20s to 50s evaluated perceived difficulty and satisfaction with opening and closing the tailgate. The results of the analysis showed that perceived difficulty and satisfaction were statistically different depending on the vehicle, but did not depend on the personal characteristics of the participants. The perceived difficulty and satisfaction regression model of tailgate opening and closing was developed by mechanical force variables and had a relatively high adjusted R2 ranging from 0.62 to 0.73. The models showed that the the initial close and open force, the difference between initial and maximum close force and the difference between initial and auto-fall angle should be small for the low perceived exertion and high satisfaction. In addition, the correlation analysis between IQS score of tailages and perceived difficulty and satisfaction showed that the IQS scores were more related to the perceived difficulty and satisfaction of closing than those of opening. The results of the study will be helpful to design and test mechanical open and close structure of SUV tailgates.

This study aimed to evaluate the perceived exertion and satisfaction in opening and closing SUV tailgates and explain them with the mechanical force. The study measured the mechanical open and close force for 42 SUV tailgates and evaluated perceived exertion and satisfaction of opening and closing with 100 male participants from 20’s to 50’s. The regression models of perceived exertion and satisfaction showed that small initial closing and opening force, difference between initial and maximum closing force and difference between initial and auto-fall angle have positive effect. The results of the study will be helpful to design and test mechanical open and close structure of SUV tailgates.

This study has been conducted on the subjects of eight undergradu˗ ate students with abdominal obesity and eight undergraduate stu˗ dents with normal weight to find out correlation between substantial fatigue and Ratings of perceived exertion through analysis of their blood components when they took exercises to strengthen their abdominal muscular power. Comparatively analyzing HDL-C, LDL-C and lactic acid before and after they took sit-up at level of RPE 19-20, no statistically significant differences in HDL, LDL, lactic acid meas˗ ures were observed between groups, but a significant difference in RPE was noted between groups(p<0.05) Our findings suggest that control group showed no significant differ˗ ence in increase of fatigue material whereas the obese group showed a lower frequency of sit-up, though both groups took the same abdominal exercise. Additionally, the lower frequency of sit-up in obese group results from relatively higher Ratings of perceived exer˗ tion rather than increase of substantial fatigue material. This study invites future research that examines the effect of a comprehensive obesity exercise program combined with dietetic

이 연구는 울트라마라토너들의 초장거리 달리기 동안의 심리적 상태를 평가하기 위해 수행되었다. 이러 한 연구 목적에 부합하기 위하여 100km 울트라마라톤 대회에 참여한 주자들(n=44)을 대상으로 총 4회에 걸쳐 각각의 체크포인트 지점(23-,54-,83-100km)에서 자각적 운동강도를 측정하였으며 이와 더불어 기분 상태 측정을 3차례(경기 직전, 54-,100km)에 걸쳐 실시하였다. 분석 결과, 울트라마라토너들은 100km의 경기에서 거리의 증가에 따라 심리적 피로의 증가를 나타냈으나 마지막 100km지점에서는 오히려 자각 적 운동강도 지수가 급격히 감소되는 것으로 확인되었다. 또한 100km 레이스의 중반지점인 54km에서 측정한 기분상태 변화에서 우울, 긴장, 분노와 같은 부정적 감정수준은 경기전에 비해 감소되었고, 100km 완주지점까지 유지됐으며, 각 구간별 기분상태 프로화일 결과 빙산형 프로화일이 나타났다. 결론 적으로 울트라마라토너들은 100km 완주과정에서 심리적 피로의 증가에도 불구하고 긍정적 기분상태를 유지한다는 것을 알 수 있었다. 이러한 긍정적인 기분상태의 경험은 초장거리 운동수행에서의 심리적 효과로서 중요하게 작용할 수 있다는 것을 시사한다.