In “the determination of fatigue in the terms of a single index”which has heretofore been an outstanding theme in the study of fatigue, some simple, method has been eagerly sought for until today for practical applications especially, on the job, not only in the field of sports, but also in the field of industrial labor as well. To meet this demand, the Flicker test has, only recently, come to draw much attention of those who are interested on the subject matter. The author, by making use of such a method, examined the effect of cold and hot stimuli to the skin (the Okuhara method) regarding the results of recovery from fatigue, the persons used for the purpose of this examination being the office clerks engaged in the daily accounting work. Thus, the values obtained by the test conducted on 10 object persons. Some of them were subjected to the stimuli for 5 consecutive days, while other were not. Then, the values of two different kinds were compared and carefully studied. From these test results, the author has reached a conclusion that such a method of giving stimuli to the skin of the daily office workers is an ideal method of restoring the fatigue of such a degree as that of the clerks engaged in the routine office work. In view of the circumstances, the author is strongly of the opinion that the Flicker test has an appreciable practical value, for such purposes mentioned above, and provides an index for a simple method measurement.
A study has been made of the relationship between the mechanical and the electrical response of the nerve muscle preparations of the frog sartorius induced by a single direct and indirect stimulation. The electrical response was recorded from the surface of the muscle, and its area and amplitude were measured. The stimulation parameters were: pulse....square wave; pulse duration....1 msec in direct and 0.01 msec in indirect stimulation; intensity.... from threshold to supramaximal. The combinations of stimulation and lead were as follows: 1) unipolar lead and direct stimulation, 2) unipolar lead and indirect stimulation, 3) bipolar lead and indirect stimulation. The data gained under these three conditions of experiment were analyzed statistically. The correlation coefficients of tension and the action potential area were from 0.896 to 0.995 (p<0.001), and those of tension and amplitude were from 0.831 to 0.996 (p<0.001) . Any significant difference was not found between these two groups of correlation coefficients. The experimental results were disccused in detail.
The subjects at present investigation were selected among people from 64 years of age to 72 (average age: 67.3 years) . For each of them the following three items were investigated and the obtained results were analyzed. 1) Step Test: The used step was 20 cm high and the subjects were made to step up ana down 5-20 times. The changes of pulse rate and blood pressure before during and after above exercise, were observed under the following three conditions. a) Voluntary exercise: No restriction of speed and of stepping number. b) Stepping up and down per one min in accordance with the rhythm of a metronome. c) The subjects were made to step up and down as quick as possible. As the result of the above observation, there was no significant difference in time necessary to step up and down 20 times and in blood pressure after exercise. However, there was found a significant difference in pulse rate during and after exercise, i. e. under the condition of c) the subjects revealed the highest pulse rate and then that under b) was higher than under a) . Under all above three conditions, the more stepping numbers increased, the higher pulse rate was. When pulse rate of 1.5 times as much as that at rest is defined as upper limit of safety10), the pulse rate under the condition of a) reached that limit at 20 times' steppings, that under b) at 15 times, and that under c) 10 times'. 2) Muscular strength of arm flexion: There was found no sigificant difference in it between the right and left arms. The right muscular strength of it was 3.02±0.2 kg in average, which was under the muscular strength of the primary school girls of the 1st grade. 3) Muscular strength of leg extension: There was also found no significant difference in it between the right and left legs. The muscular strength of the right leg was 78.4±0.75 kg in average, which was under the value of the primary school girls of the 3rd grade. It was observed that both the above muscular strengths were remarkably decreased by aging. Therefore, it could be assumed that aged people got harder to step up and down rather due to weakened muscular strength of their legs.