ABSTRACT
This study examined competitive wheelchairs that facilitate sports participation. They can be moved straight ahead using only one arm. Our designed and developed competitive wheel-chairs have a dual hand-rim system. Their two hand-rims, attached to a drive wheel on one side, can be operated simultaneously for straight-ahead movement. Specifically, based on integrated electromyography (iEMG) data calculated from surface electromyography (sEMG), we examined the wheelchair loading characteristics, posture estimation, and effects on body posture during one-arm propulsion movement. The first experiment yielded insights into arm and shoulder-joint muscle activation from iEMG results obtained for two-hand propulsion and dual hand-rim system propulsion. Results suggest that muscle activation of one arm can produce equal propulsive force to that produced by two arms. The second experiment estimated the movement posture from iEMG during one-arm wheelchair propulsion. The external oblique abdominis is particularly important for one-arm wheelchair propulsion. The iEMG posture estimation validity was verified based on changes in the user body axis and seat pressure distribution. In conclusion, as confirmed by iEMG, which is useful to estimate posture during movement, one-arm wheelchair use requires different muscle activation sites and posture than when using two arms.
Subject(s)
Wheelchairs , Biomechanical Phenomena , Electromyography , Posture/physiology , Shoulder/physiologyABSTRACT
(1) Background: When measuring anaerobic work threshold (AT), the conventional V-slope method includes the subjectivity of the examiner, which cannot be eliminated completely. Therefore, we implemented an engineering method using strucchange to objectively search for the inflection point of AT. (2) Methods: Seventeen subjects (15 men and 2 women) were included in the study. The subjects rode an ergometer and performed a ramp load test for 18 min and 30 s. (3) Results: In VE (Ventilation), 11 out of 12 subjects had the same results with 95% confidence intervals for the AT by the strucchange and respiratory metabolic apparatus. In VCO2 (Carbon dioxide emissions), 9 out of 12 subjects had the same results with 95% confidence intervals for the AT with the strucchange and respiratory metabolic apparatus. In VE, 3 out of 12 subjects showed the same results for respiratory metabolic analysis and the AT by the V-slope method. In VCO2, 3 out of 12 subjects showed the same results for the respiratory metabolic analysis and AT by the V-slope method in VCO2. (4) Conclusions: Strucchange was more objective and significant in identifying the AT than the V-slope method.
Subject(s)
Anaerobic Threshold , Oxygen Consumption , Carbon Dioxide/metabolism , Exercise Test , Female , Humans , Lung , Male , Pulmonary Ventilation , RespirationABSTRACT
In some previous studies, transcutaneous electrical nerve stimulation (TENS) to the back was shown to improve non-verbal short-term and long-term memory as well as verbal fluency in patients in the early stage of Alzheimer's disease (AD). Moreover, the patients' physical, social and affective functions were also improved. In this study, the effects of TENS applied to the face were studied in patients with mild and severe AD. Fourteen patients with probable AD were used as subjects. To evaluate the effects of treatment, the subjects underwent two kinds of neuropsychological tests as well as a pupillary light reflex test. The pupillary light reflex test was chosen because it has been proven to show poorer results in cases of senile dementia. These three tests were carried out before the treatment, immediately after the treatment and 6 months after the treatment. Improvements were seen in subjects in the TENS groups and the effects of treatment were more significant in mild AD patients than in severe AD patients. However, the improvements were not maintained 6 months after the treatment. The possible mechanisms underlying the beneficial effects of TENS in AD patients are discussed in this paper.
