Japanese Journal of Physical Fitness and Sports Medicine
Online ISSN : 1881-4751
Print ISSN : 0039-906X
ISSN-L : 0039-906X
Volume 32 , Issue 5
Showing 1-6 articles out of 6 articles from the selected issue
    1983 Volume 32 Issue 5 Pages 259-268
    Published: October 01, 1983
    Released: September 30, 2010
    Preliminary studies on the blood composition were carried out with 40- to 82-year-old runners when they were at rest. 790 male subjects who had kept the routine training of running over a year were examined. And the results were compared those with the corresponding control groups who had no particular routine training.
    The results were as follows:
    1. Runners' values for Red blood cell count and Hematocrit were decreased with age.
    2. Runners' values for Red blood cell count, Hemoglobin and Hematocrit were approximately 10%, 9% and 4% lower than those of the corresponding control groups of almost all age groups. On the other hand runners' values for MCH (Mean Corpuscular Hemoglobin) were approximately 8% higher than the control group values for all age groups.
    3. Runners' values for reticulocyte count and osmotic fragility of the blood were within normal range.
    4. Comparison between runners of 10 km group and 25 km group of blood composition was made; the age group of forties of 25 km group of both Red blood cell count and Hematocrit were significantly lower than the corresponding 10 km group.
    5. Dailly training programs of 25 km runners were significantly longer than those of 10 km runners for all age groups.
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    1983 Volume 32 Issue 5 Pages 269-277
    Published: October 01, 1983
    Released: September 30, 2010
    Physiological characteristics of middle-aged and old runners, who competed in the international 10km or 25 km race, were investigated. All of 2260 runners were aged 40 to 86 years. They have been trained for at least one years. Body composition, resting blood pressure, blood composition, serum metabolites, serum enzymes and pulmonary function were measured. The runners who competed in 10 km race were compared with those competed in 25 km race. Relation between running performance and physioloigical parameters were discussed.
    1) Average running speed was faster in 25 km group than in 10 km group, although 25 km group ran a longer distance. In daily training, 25 km group also showed longer running distance than in 10 km group.
    2) Body weight averaged 55.9±6.82 kg in a whole group of 2260 runners. Skinfold thickness averaged 6.1±2.50 mm in triceps, and 10.9±3.78 mm in subscuplar. These values were remarkably lower than normal values of corresponding age of the Japanese. 25 km group showed significantly lower values in these parameters than 10 km group. The runner who made better performance also showed lower values in these parameters.
    3) Resting blood pressure of the runners averaged 144.3±17.0 mmHg in systole, and 86.2±11.0 mmHg in diastole. No difference were found between 10 km group and 25 km group in blood pressure.
    4) RBC, Ht, Hb of 645 runners averaged 411.8±37.4×104/mm3, 40.3±3.70%, 14.5 ±1.25g/dl, respectively. These values were lower than in normals. Among age group of 40-49yrs, negative correlation between running speed and these heamatological parameters were found. Better runner showed lower values in these parameters.
    5) Blood glucose, serum choresterol, LDH and CPK were not different from normal values.
    6) Pulmonary function were not different from normal values. Remarkable decrease with increasing age were found in pulmonary function.
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    1983 Volume 32 Issue 5 Pages 278-284
    Published: October 01, 1983
    Released: September 30, 2010
    Many studies have been conducted on the monosynaptic reflex (H-reflex) changes which occur before a voluntary movement in man. Especially, it has been shown that there were the changes of H-reflex prior to the rapid plantarflexion movement which was called the premotor inhibition.
    In the present study, the changes in soleus H-reflex prior to a choice reaction time (RT) were studied, giving the special attention to the possible functional difference of motor patterns to generate the premotor inhibition during a period when the physiological mechanisms involved in the movement.
    The changes of H-reflex were measured in choice RT experiment in 9 and 6 male subjects under the different two conditions : (a) selection of the response sides (left or right plantarflexion) -the movement pattern was known before the presentation of a response signal ; and (b) selection of the movement patterns (plantar or dorsiflexion) -the responce side was known before.
    The premotor inhibition was observed only in case of (a), and was dependent on a prerequisite for movement patterns. Moreover, the physiological significance of this phenomenon was indeed related to a presynaptic inhibition, and was related to a modulation of alpha-motoneurone excitability by the pyramidal system. Thus, the premotor inhibition might be related to central motor preprogram controlling presynaptic inhibition on the reflex pathways.
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    1983 Volume 32 Issue 5 Pages 285-292
    Published: October 01, 1983
    Released: September 30, 2010
    This study was undertaken to examine the mechanical efficiency of stepping exercise on the relations with physical characteristics such as body height, lower limb length, leg length and body weight, and the efficiency was used to estimate the energy metabolism during the stepping exercise. Thirty healthy male students, whose heights ranged from 157.6 cm to 189.0 cm, performed the stepping exercise using a platform from 10 cm to 50 cm. The stepping rate of vertical lifts per minute was fixed to 25 ascents/min., and the height of the platform was increased progressively by 10 cm on every 3 minutes. Oxygen intake during the stepping exercise was measured for the last 1 minute on every stage. Gross, net, work, and delta efficiencies were compited. The results were summarized as follows:
    1. It was suggested that there was slightly exponential relationship between energy metabolism and work rate, which was ascribed to the decrease of work and delta efficiencies with increments in work of the stepping exercise.
    2. The correlation coefficients between the net efficiency and each physical characteristic were not signifficant for all heights of the platform. This result suggests that the physical characteristics have little or no effect on the mechanical efficiency of the stepping exercise.
    3. The mean value and the standard deviation of the net efficiency for heights of the platform above 30 cm were 14.3 and respectively. By using this mean value, energy metabolism during the stepping exercise can be calculated from the equation : Y=0.0163×weight (kg) ×stepping rate (ascents/min.) ×height of the platform (m) +resting energy metabolism (kcal/min.) . The standard error of estimation was ±0.52 kcal. This value was lesser than that calculated from the regression equation between heart rate and oxygen intake during the stepping exercise.
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    1983 Volume 32 Issue 5 Pages 293-301
    Published: October 01, 1983
    Released: September 30, 2010
    It was the purpose of this study to elucidate the difference between endurance runners and normal men in respiratory and circulatory adjustments during prolonged exercise, and to evaluate the relationship between the magnitude of the respiratory and circulatory“drift”and the endurance exercise capacity.
    Ten male endurance runners (runner group), aged 19-23 years, and nine normal men (control group), aged 19-28 years, exercised on a bicycle ergometer for 60 min at a constant work load requiring 60% of Vo2max for each subject.
    In the control group, VE increased approximately 20% from 10th to 60th min of prolonged exercise (P<0.05), with a corresponding decrease in PAco2 (P<0.05), whereas in the runner group VE and PAco2were remained constant throughout prolonged exercise. The above differences of VE and PAco2responses between the control and the runner group could not be accounted for by a rising body temperature and lactic acidosis, because it was found that the magnitude of the rise in rectal temperature (Tre) and the behavior in lactic acid (LA) were not different for the two groups. On the other hand, we failed to find the difference of the pattern in HR and SV responses to prolonged exercise in the runner group as compared with the control group. At each comparable time period during prolonged exercise, however, the percentage changes from the values at the 10th min in HR and SV were less in the runner group than in the control group. In addition, Vo2max (ml/kg/min) correlated significantly with the percentage changes in VE (r=-0.534, P<0.05), HR (r=-0.565, P<0.05), and SV (r=0.588, P<0.01) from 10th to 60th min of prolonged exercise.
    The results of this study suggest that the endurance training may improve the magnitude of the respiratory and circulatory “drift”, which appears to become a limiting factor to endurance performance.
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    1983 Volume 32 Issue 5 Pages 302-309
    Published: October 01, 1983
    Released: September 30, 2010
    Eighty healthy males aged from 26 to 34 years were studied to evaluate the effects of regular physical training on body composition, respiratory functions, circulatory functions, blood constituents, and physical fitness. The physical training consisted of jogging, volleyball, handball, socker, judo, fencing, and others. The combination of these sports were assigned to all the subjects to be performed for 130 minutes every week-day from April, 1979 to January, 1980.
    1) The subjects had, on the average, 518 g of carbohydrate, 125 g of protein including 74 g of animal protein, and 85 g of fat summing up to 3300 kcal a day. These nutrients intake was 30% to 50% excess over the normal value for male Japanese of the corresponding age. Body weight, however, did not change and body fat decreased in spite of large excess food intake. Serum HDL-cholesterol increased and atherogenic index decreased. These facts lead to a conclusion that the noxious effects of overeating can be cancelled by physical activity.
    2) Pulse wave velocity of the aorta which reflects the elasticity of the aortic wall decreased. This means that changes in the physical property of the aorta due to aging process can be reversed through physical training. Decrease in pulse wave velocity dose not always mean the regression of atherosclerosis, but the additional findings such as decrease in body fat and in atherogenic index and increase in HDL-cholesterol support the possibility of regression of aterosclerosis by physical activity.
    3) The results of physical fitness test indicated marked improvement of physical abilities which reflect muscular strength, muscular power, muscular endurance, body flexibility, agility, anaerobic power, and aerobic power.
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