THE STUDY ON THE INFLUENCE OF THE KENDO TRAINING TO THE BODY FUNCTION OF FEMALE / 体力科学

The physical fitness of four well trained female on “Kendo” were tested and the results were as follows.<BR>1) The grip strength grading ability of the subject was excellent than that of untrained female.<BR>2) The reaction time was prolonged at the menstrual flow stage.<BR>3) The grip strength and their grading ability were not influenced by the ovarial cycle.<BR>4) The grip strength grading ability wasn't drop even if the test has been done immediately after the heavy Kendo training.

GRADING ABILITY OF KENDO ATHLETES / 体力科学

Kendo champions were measured in order to study neuromuscular coordination on blow and to examine influence of Kendo athletics on fundamental human grading ability about grading grip and standing broad jump graded. The results were as followes.<BR>1) As subjects were ordered to voluntarily show one-third, one-second and two-thirds of his own maximum grip strength after checking his maximum value, no discrepancy of voluntary grip strength and ordered strength was shown between well trained Kendo champions and beginners. Standard deviation values of ten times grip strength were not much different between them.<BR>2) As subjects were ordered to voluntarily show one-third and two-thirds of his own maximum standing broad jump after checking his maximum, no discrepancy of voluntary value and ordered value was shown between well trained Kendo champions group and weight training group. Standard deviation values of thirty times jump record were not much different between two groups.<BR>3) Well trained Kendo champions and beginners were measured in blowing down with bamboo-sword at three different distances. In spite of beginners showed varied moments of blow and foot touching the floor when distance was changed, well trained Kendo champions showed uniform moment of them.

STUDY ON THE ERROR THAT WAS ACCOMPANIED WITH BODY GIRTH / 体力科学

10 male and 8 female skillful tester on physical fitness measurements were attended. They were measured one another the body girth and blood pressure of themselves. The result obtained on the same person by the different tester were not always coincident. The following issues were obtained.<BR>(1) Mean value of individual error finding on the systolic pressure was about 4mmHg, on the diastolic pressure was about 6mmHg. Mean value of the difference between the maximum and minimum value of the systolic pressure reported on the same person was 15.4mmHg in male group. That of the diastolic value was 21.4mmHg in male group. For the female group, that of the systolic pressure was 17.0mmHg, that of the diastolic pressure was 23.0mmHg.<BR>(2) Mean value of individual error (as under, be showed by“error”) obtained on the chest girth was 1.43cm in male group, 1.05cm in female group. Mean value of the difference between the maximum and minimum value (as under, be showed by“breadth”) was 5.99cm in male, 4.08cm in female.<BR>(3) “Error”observed on the overarm extended girth was 0.73cm in male, 0.79 cm in female, “breadth”was 2.96cm in male, 2.99cm in female.<BR>(4) “Error”finding on the overarm flexed girth was 0.60cm for both sex, “breadth”was 2.81cm in male, 2.43cm in female.<BR>(5) For the forearm girth, “Error”was 0.40cm in male. 0.24cm in female, “breadth”was 1.81cm in male, was 1.35cm in female.<BR>(6) For the thigh girth, “Error”was 0.90cm in male, 0.69cm in female, “breadth”was 3.91cm in male, 2.93cm in female.<BR>(7) On the calf girth measurement, in male and female group, “Error”was 0.44 and 0.40cm, “breadth”was 1.51 and 1.48cm respectively.<BR>From above mentioned findings, we considered that“Error”is possible to regard as unavoidable error, “breadth”might be probable error.

ON SOME INDICATORS OF THE CAPABILITY TO EXERT MUSCLE FORCE OF HUMAN BODY FROM THE STAND POINT OF THE TIME COURSE OF TENSION DEVELOPMENT OF ISOMETRIC TETANUS / 体力科学

1) The time course of nearly isometrical tension development of human voluntary muscular contraction was analyzed for the purpose of finding some desirable indicators of the capability of human body to exert maximal muscle force as fast as possible.<BR>2) The isometric tension curves of maximal exertion of hand gripping, arm and indexfinger bending recorded, the linear relation between P<SUB>max</SUB>-P, which is a difference between its maximal tension and each value of tension in the time course, and log t, which is the logarithm of time corresponding to each value of tension, was found in each of three portions of a whole curve of time course of tension, the three portions being a range from P<SUB>0</SUB> (log t<SUB>0</SUB>) to P<SUB>1</SUB> (log t<SUB>1</SUB>), from P1 (log t<SUB>1</SUB>) to P<SUB>2</SUB> (log t<SUB>2</SUB>) and from P<SUB>2</SUB> (log t<SUB>2</SUB>) to P<SUB>max</SUB> (log t<SUB>max</SUB>.) respectively.<BR>3) The range from P<SUB>1</SUB> (log t<SUB>1</SUB>) to P<SUB>2</SUB> (log t<SUB>2</SUB>) is a phase in which the tension increases most rapidly from an initial small tension to a large tension and is, therefore, regarded as a most characteristic one with respect to the time course of muscle force development exerted voluntarily as fast as possible.<BR>4) The angles of intersection of the line connecting P<SUB>1</SUB> (t<SUB>1</SUB>) with P<SUB>2</SUB> (t<SUB>2</SUB>) or P<SUB>1</SUB> (log t<SUB>1</SUB>) with P<SUB>2</SUB> (log t<SUB>2</SUB>), with the abscissa in the tension-time or tension-log t curve, which are denoted as or respectively, were found to be able to be adopted as indicators of the capability of human body to exert maximal muscular force for a short period of time.<BR>5) The tension curves were found to be nearly the same each other when they were recorded three or four times in the interval of 30 seconds with one and the same subject. If the difference is small between the first and the second record of the time course of a given subject, either of them may be adopted, but if not so, one have to only record the third curve and adopt either of the two resembling each other among the three records.<BR>6) Concerning the subjects of the same age, the difference between P<SUB>max</SUB> and P<SUB>2</SUB> was small and the tan was large with a subject whose P was large. The tan ψ or tanθ was as a rule smaller with subjects of middle and high ages than with younger ones.<BR>7) The Pmax decreased with lapse of time when the maximal effort of contraction whose duration was one second was repeated in the interval of three seconds for two minutes. Under this condition the tan ψ increased in some cases, but did not in other cases. Also there were some cases in which t<SUB>1</SUB> remained constant in spite of a decrease in the P<SUB>max</SUB> with subjects of middle and high ages, P<SUB>1</SUB> of them decreased with decreasing t<SUB>1</SUB>. In short the change of the characteristics of the tension curves due to fatigue showed some individual variation.<BR>8) The decrease in the P<SUB>max</SUB> during a continuation of maximal effort of contraction was more remarkable than in the case of repeated contraction mentioned above, but the changes of the values of indicators were nearly the same in both cases.<BR>9) The P<SUB>max</SUB> of hand gripping and index-finger bending decreased to some extent when examined immediately after the effort of contraction had been continued under the condition that the blood stream in the fore-arm was stopped by applying the maximal blood pressure by a manchette of sphygnomanometer. The change of the values of the indicators under this condition was nearly the same as under the condition without the application of pressure, but under the former condition there were some cases in which a portion of the tension curve corresponding to P<SUB>1</SUB> (log t<SUB>1</SUB>) deviated from the intersection of the lines, or some cases in which the records of one

ON THE SIGNIFICANCE OF THE REACTION TIME OF AVOIDANCE MOVEMENT FROM THE STANDPOINT OF AN INDICATOR OF THE PHYSICAL FITNESS OF HUMAN BODY / 体力科学

1) The reaction time of the avoidance movement of jumping off toward a given place, which was regarded as an indicator of the quickness of movement of the group of muscles of the lower limbs, was measured and compared with the quickness of these of the upper limbs.<BR>2) The reaction time of movement of placing one's hand from one to the other of the two pushing-plates, by pushing which the electric circuits were closed, was measured. The reaction time of the commencement of the movement was similar to the simple reaction time, and its correlation with age was not high. The time taken to place one's hand on the other plate tended to be a little longer with subject of middle and high ages.<BR>3) The dispersion of the values of reaction time of both the commencement and the termination of movement when measured repeatedly was similar to that of the simple reaction time, but the dispersion of the difference between these two kinds of reaction times, that is, that of the time taken to move one's hand was smaller than that of the simple reaction time.<BR>4) Concerning one-step jumping aside to the right hand side, the reaction time of the commencement of movement under the condition that the legs were moved one by one was longer than the simple reaction time, and was also longer than that of the simultaneous movement of the both legs. The reaction time of both the commencement and the termination of movement was longer with higher ages, and was longer with women than with men. This relation was more evident in the successive movement of each legs than in the simultaneous one. The frequency distribution curve obtaind by repeating the measurement of the reaction time of jumping off showed a nearly normal distribution curve. The correlation between the reaction time of hand movement and that of jumping off was not so high.<BR>5) The scattering of the landing position of one-step jumping aside to the right hand side did not show any correlation with the values of the time taken to move one's legs.There was, however, a high correlation (r=+0.96) between the scattering of the landing position and that of the reaction time.<BR>6) There was no large difference between the reaction time of one-step jumping aside to the right hand side and that to the left hand side. With respect to forward jumping, the period of time during which the pressure at the first pushing-plate remained equal to the body weight was longer when the both legs were not simultaneously moved. There was no large difference between forward and backward jumping.<BR>7) The variation of the reaction time of two-steps jumping with respect to age was similar to that of one-step jumping.<BR>8) The results mentioned above indicate that one-step jumping aside is to be adopted as an indicator of the quickness of movement of the group of muscles of the lower limbs, and that it is practically useful to measure the time taken for one's one leg to tread on the second pushing-plate.

ON THE VOLUNTARY CONTROL OF MUSCLE FORCE / 体力科学

The pressure exerted by the index finger tip was continuously recorded while the human subject was trying to maintain the pressure at the level of a given pressure (this pressure is named ‘target pressure’, 0.5-500g) with optical information for ten minutes, and the results obtained under various conditions were analysed.<BR>1) The errors tended to be minimal in the range between 40 and 50g target pressure, and increased approximately in proportion to the target pressure above 50g.<BR>2) When the subject relaxed his index finger, the errors decreased with decreasing target pressure in the range of less than 50g.<BR>3) The errors were increased by excluding optical information. In target pressure less than 50g, the increment of the errors due to a decrease in the skin pressure intensity was further increased by exclusion of optical information.<BR>4) In small target pressures, the errors tended to decrease transiently in evening, while in large target pressures the errors showed a gradual increase from morning toward evening.<BR>5) The errors showed generally minimal values 2 or 3 minutes after the beginning of the measurement, and thereafter increased more remarkably in large target pressures than small ones.