1.STUDY ON HUMAN INTRAGASTRIC PRESSURE DURING EXERCISE
KINJI UCHINO ; SEIJI SATO ; MAKOTO MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1978;27(3):91-99
Intragastric pressure at gastric empty state was measured by radio capsule method during various exercises in three human subjects. The E. I. L. Type. 70. pressure sensitive radio capsule of England make was used in this experiment.
1) The empty intragastric pressure at rest was 30.0-33.0 cmH2O and the gastric peristalsis was 2-3 sec. in frequency and less than 3 cmH2O in amplitude.
2) The resting gastric peristalsis was disappeared immediately after the onset of deep respiration or exercise. The pressure raised to maximum 76.0 cmH2O at the end of deep abdominal inspiration.
3) The intragastric temperature raised during various exercises and increasing grade was showed in Table of the text.
2.PERSONAL SPACE PERCEPTION IN HUMAN SHOULDER ON THE HORIZONTAL PLANE
HIROSHI KURATA ; JUNKO MIYAZAKI ; YOSHINORI OGAWA ; MAKOTO MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1981;30(4):214-219
To examine the personal space perception, measurements were conducted on both arms in 227 young men and women. Each subject, with his eyes closed, was instructed to stop the horizontal swing motion of his arm at the point he considered to be the middle of the range of possible motion on the horizontal plane, and this was repeated ten times.
Mean values of bisected angles were deviated from the middle points in the direction of the horizontal adduction, although there were large differences between the individuals. The deviation was larger in the right arms than that in the left, and it increased with the increasing range of motion of the horizontal abduction.
It was suggested that the gain of the personal space perception is higher in front of the body than in the side on the horizontal plane of the human shoulder.
3.CHANGES IN CHARACTERISTICS OF RECRUITMENT MODES IN HUMAN MOTOR UNITS AT VOLUNTARY MUSCULAR RELAXATION
SHIGERU MORIMOTO ; TOSHIO OHMORI ; HIDESHI HASEGAWA ; HIROSHI KURATA ; MAKOTO MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1977;26(2):59-63
It had been proposed by Kurata that relative threshold value Fth of single motor units depends on the gradient G (kg/sec) of the tension increase of muscle in such a manner as
Fth (≡T.G) =ρGλ
Here T1 is the time interval from the onset of EMG to the moment of recruitment of a motor unit and ρ is a proportional constant. The motor unit with a positive/negative value of λ is characterized to be static/phasic.
Morimoto and Hasegawa reported that the above relation also holds for the relaxation period, provided that Ftn and G are replaced by the tension at the moment of silence and the absolute value of G, respectively. In this case, the motor unit with a positive/ negative value of λ is characterized to be phasic/static.
In order to investigate the characteristics of motor units during relaxation period under the influence of pre-relaxation states, such as the increase of tension up to 4kg at the gradient of 0.5kg/sec and the state sustained at 4.0kg for 30sec. Single motor units of m, vastus medialis were studied by the same method as that of Morimoto and Hasegawa.
The following results were obtained;
1) Both at contraction and relaxation periods, the above relation was confirmed.
2) The motor unit with characteristics of recruitment modes was influenced by the pre-relaxation state, but its tendency was not definite. These results suggest that phasic/static characteristics of motor units are not stationary but fluctuate depending on the pre-relaxation states.
4.RELATIONSHIP BETWEEN THE TWITCH TENSION CURVE AND DISCHARGE PATTERN IN SINGLE HUMAN MOTOR UNITS
HIROSHI KURATA ; HIDESHI HASEGAWA ; SHIGERU MORIMOTO ; YOSHIKI UMAZUME ; MAKOTO MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1977;26(2):70-77
In this study, the relationships between the contractile properties of human motor units and their discharge patterns, characteristics of recruitment and others were examined. Action potentials of single human motor units in m, extensor digiterumwere detected by use of an inserted electrode. Tension curves of single motor units were recorded under the conditions that tension in finger extension was gradually increased, and that the subject relaxed his muscle as soon as he observed a sweep on a Braun tube triggered by the action potential of a single motor unit. About 100 twitch tension curves were summed up to obtain the average tension curve of a single motor unit. The τ-S diagrams were obtained from the mean discharge intervals (τ) of motor units at various sustained tensions and their standard deviations (S) . The λ values were also obtained from the relation Fth (-T1G) =ρGλ.
It was observed that the contraction time of the twitch tension curve of single human motor unit in a muscle was nearly proportional to τs (the τ values at a constant S value) . We presume that the regularity of discharging of motor unit affects the contraction speed in human muscle, because the motor unit with more regular discharging has longer contraction time of twitch.
5.HEART RATE AND R-R INTERVAL DURING SLEEP
MAMORU NISHIMUTA ; MAKOTO MASUDA ; KINJI UCHINO ; TOSHIO OOMORI
Japanese Journal of Physical Fitness and Sports Medicine 1978;27(1):25-30
Heart rate and R-R intervals of ECG during sleep were examined in healthy young men. Heart rate per minute were gradually decreased when the subject fell asleep. Whole through one night sleep data there were two typical heart rate variation patterns, namely stable stage and fluctuating stage. Sleep stages determined by EEG, EOG and EMG of chin corresponded with these two patterns; slow wave stage (Stage III/IV) showed the stable pattern, REM Stage and Stage I showed the fluctuating pattern, Stage II both patterns. The fluctuating pattern showed higher heart rate level.
Further studies computed R-R intervals and its variations of ECG revealed 4 typical patterns on the variations, and well corresponded with sleep patterns determined by the above methods. R-R interval varied from 1.39 to 0.67 sec during sleep. R-R interval variation befor onset of sleep showed lightly rythmical periodicity (20-40 sec) and small fluctuation (0.1 sec) (awaking pattern) . R-R intervals after onset of sleep extended gradually, fluctuating midly (0.1 sec) and did not show any periodicity (transient pattern) . R-R interval reached its maximum level then. At slow wave stage (S-III/IV) R-R interval showed mild fluctuation as the transient strage, and did not show any periodicity (stable pattern) . At REM stage and S-I it showed large fluctuation (more than 0.2 sec) and significant periodicity (10-30 sec) . At S-2 if the stage was in the course of deepening the sleep, it showed stable pattern and if it was in the course of lightening the sleep it showed fluctuating pattern.
6.Difference in effects between "power-up type" and "bulk-up type" strength training exercise. (2). With special reference to muscle histochemical properties and capillary supply.
JOYEON CHOI ; KAZUMI MASUDA ; MAKOTO MURAOKA ; HITOSHI SHIMOJO ; KAORU TAKAMATSU
Japanese Journal of Physical Fitness and Sports Medicine 1998;47(2):189-197
A training experiment was carried out to investigate the difference in training effects between power-up type and bulk-up type strength training exercises from the aspects of muscle histochemical properties and capillary supply. The subjects were eleven healthy males. The power-up type group (five males) performed knee extension exercise for 5 sets at 90% of 1 RM (one repetition maximum) with a 3-min rest between sets (repetition method) . The bulk-up type group (six males) performed the same exercise for 9 sets at 80-40% of 1RM with a 30-s or 3-min rest between sets (interval method, multi-poundage system) . Both programs were carried out twice a week for 8 weeks.
The main results were as follows ;
1. Percentages of fiber types showed no recognizable changes in either group.
2. Fiber area was significantly increased for all fiber types (Type I, Type IIA, Type JIB) in both groups. However, the rate of increase was greatest for type IIA fiber, followed by type JIB fiber and then type I fiber. Moreover, the rate of increase for all fiber types in the bulk-up group was higher than that in the power-up group.
3. Percentage of fiber area showed no recognizable changes for any fiber types in the powerup group. However, the percentage area of type II fibers, especially type IIB fiber, was significantly decreased in the bulk-up group.
4. CC (Type I), CC (Type IIA) and CC (Type IIB) (number of capillaries in contact with each fiber type) were significantly increased in both groups. However, in comparison with CC (Type I), CC (Type IIA · Type IIB) showed a higher rate of increase in the power-up group. On the other hand, in comparison with CC (Type IIA · Type JIB), CC (Type I) showed a higher rate of increase in the bulk-up group. Also, compared with the power-up group, the bulk-up group showed a signifi-cantly higher rate of increase of CC (Type I) .
5. C/Fiber area (Type I), C/Fiber area (Type IIA) and C/Fiber area (Type IIB) (number of capillaries supplying each fiber area) were decreased in both groups.
The above results show that power-up type exercise leads mainly to hypertrophy of type I, type IIA and type IIB fibers without any change in percentage fiber type or percentage fiber area, whereas bulk-up type exercise leads mainly to hypertrophy of each fiber type with decreases in percentage area of type II fibers, especially type JIB fiber. Also, power-up type exercise leads mainly to an increase in the number of capillaries around type II fibers, whereas bulk-up type exercise leads mainly to an increase in the number of capillaries around type I fiber. However, capillary development around all fiber types did not necessary coincide with muscle hypertrophy in either exercise.
The authors reported previously that power-up type exercise is effective mainly for improving muscular strength and anaerobic power, whereas bulk-up type exercise is effective mainly for induc. ing hypertrophy and anaerobic endurance. The results of this study may help to clarify these effects from the viewpoint of the adaptations of muscle fibers and the capillary supply.
7.Gender differences in body fat distribution of 3- to 6-year-old japanese children.
KODO OTOKI ; SHUICHI KOMIYA ; KEISUKE TERAMOTO ; TAKASHI MASUDA ; MAKOTO UBE
Japanese Journal of Physical Fitness and Sports Medicine 1999;48(5):641-649
A study was conducted to assess gender differences of body fat distribution (i. e., total body fat mass, subcutaneous fat mass, and internal fat mass) in a homogeneous group of Japanese children. Body composition was estimated in 141 boys and 139 girls (aged 3-6 yr) using bioelectrical impedance analysis (BIA) . All subjects were apparently healthy. Determinations of impedance were made using a four-terminal impedance analyzer (TP-95 K, Toyo Physical, Inc., Fukuoka) . The lean body mass (LBM) was calculated using the equation of Kushuner et al. (1992) and Goran et al. (1993) . Total body fat mass (TFM) was calculated as the difference between body weight and LBM. The subcutaneous fat mass (SFM) was calculated using a modification of the equation derived by Skerjl et al. (1953) . The internal fat mass (IFM) was calculated as the difference between TFM and SFM. From ages 3 through 6 years, the mean LBM increased with age in boys and girls, but showed no significant gender differences. There were also no obvious gender differences in TFM and IFM within the same age range. Percentage body fat decreased in both sexes until the age of approximately 5-yr, and then increased again slightly at 6 yr, although it showed no significant differences between the sexes. The gender-specific pattern of fat accumulation during childhood was characterized by an almost steady increase of SFM in girls. These differences were independent of gender differences in physical characteristics.
8.HABITUAL ACTIVITY, FOOD INTAKE AND FATTY MASS
CHIKAKO WAKANA ; MICHIKATSU KONNO ; TETSURO OSAKA ; MAKOTO YASUNAGA ; TOSHIKI CHIWATA ; TAKUJI MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1981;30(5):253-258
Measurement of maximal aerobic power (MAP), food intake and fatty mass (%Fat) were carried out on 104 males aged 20-49 years living in suburban, rural and moun-tainous districts as a basic research for determing successful living conditions in modern society or in future ages. Measurement of MAP was made indirectly follow-ing the method of Margaria et al. Each subject screened medically was given two different intensities of step up and down exercises, and MAP was calculated from heart rates immediately after exercises and the individual's estimated maximal heart rate. Observation of food intake was conducted by a routine qusetioning, however, checks and counterchecks were made by personal interview until reliable figures had satisfactrily been obtained. %Fat was estimated from skinfold thickness according to the method of Nagamine.
No age differences were found in MAP and 2oFat. Significant negative correlations were found between %Fat and caloric intake per kilogram of body weight per day (P<0.01) and between %Fat and MAP per kilogram of body weight per minute (P< 0.01) . A weak negative correlation was found between %Fat and caloric intake per kilogram of lean body mass per day. A significant positive correlation was found between MAP per kilogram of body weight per minute and caloric intake per kilogram of body weight per day (P<0.05) . Therefore, it is said clearly that physical inactivity rather than excessive caloric intake is associated with the development and mainte-nance of obesity.
Caloric intake and each nutrient intake of UO (Unfit Obese, MAP below 40m1/kg/ min & %Fat above 15%) group and UN (Unfit Non-obese, MAP below 40 ml/kg/min & %Fat below 15%) group were less than those of FN (Fit Non-obese, MAP above 40 ml/kg/min & %Fat below 150) group, respectively, and differences of those intakes between UO group and UN group were not significant. Mean calcium intake of UO group and UN group were less than the recommended allowance value of 10 mg/kg/ day. Both of MAP per kilogram of body weight per minute and per kilogram of lean body mass per minute of FN group were higher than those of UO group and UN group (P<0.01, respectively) . However, differences of mean MAP were not found significantly between UO group and UN group. It is considered that physical inac-tivity is not always associated with obesity, however, it is said from the health scien-tific point of view that fit non-obese man is more desirable than unfit non-obese one.
9.A COMPALATIVE STUDY OF MAXIMAL AEROBIC POWER BETWEEN SEDENTARY GROUP IN MODERN SOCIETY AND ACTIVE GROUP IN PRISTINE SOCIETY
TETSURO OSAKA ; MICHIKATSU KONNO ; NORIKO WADA ; MAKOTO YASUNAGA ; YUTAKA YOSHIMIZU ; TAKUJI MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1982;31(3):172-177
A compalative study of maximal aerobic power (MAP) with special reference to age were carried out as a basic study for determing the optimal physical load for successful living in modern society or in future ages. 169 males who have a sedentary living style profoundly affected by the motorization, 10-69 years of age, in suburban district of Fukuoka City (JAPAN) and 54 males who have a natural living style, 16-55 years of age, in rural districts of Nepal were selected as subjects. Measurement of MAP was made indirectly following to the method of Margaria et al.. Each subject were given two different intensity step up and down exercises, and MAP was calculated from heart rates immediately after exercises and individual's estimated maximal heart rate. % Fat was estimated from skinfold thickness according to the method of Nagamine.
Statistically significant correlations were found both of Japanese group (r= -0.554, P<0.001) and Nepalese group (r=0.561, P<0.001), and each regression equation etween MAP (ml/kg/min) and Age (yr) were as follows :
MAP=-0.350 Age +52.121 in the case of Japanese group.
MAP=-0.446 Age +63.395 in the case of Nepalese group.
However, difference of the regression coefficient was not significant.
Mean MAP per kilogram of body weight or per kilogram of lean body mass of every Japanese age groups wese lower than those of Nepalese groups with coincidental age, respectively. Generally, it is said that the socio-economical condition of Nepal today is a similar to that of Japan in the Meiji era. Therefore, it may be considered that modernization or urbanization have lowerd the system of Japanese people.
According to the review of literatures concerning to the living style and MAP in a evolutional and comparative point of view, it may be considerd that human races have maintained the relatively high MAP like Nepalese group today. Therefore, it is said conclusionally that the maintenance of mean MAP like Nepalese group is desirable in modern society or in future ages to prevent the degeneration of functions attributing the new health problem of modern society.
10.PERSONAL SPACE PERCEPTION IN HUMAN ELBOW JOINT
JUNKO MIYAZAKI ; HIROSHI KURATA ; YOSHINORI OGAWA ; YOSHIHIRO SAITO ; ATSUSHI TOKIOKA ; KUNIHIKO HARADA ; SOTOYUKI USUI ; MAKOTO MASUDA
Japanese Journal of Physical Fitness and Sports Medicine 1982;31(4):242-250
In order to examine the personal space perception, measurements were conducted on both elbows in 14 men and 46 women. Each subject, with his (or her) eyes closed and with his upper arm fixed horizontally, was instructed to stop the vertical and horizontal swing motion of his lower arm at the point he considered to be the middle of the range of possible motion on the front and side of plane at his shoulder, and this was repeated ten times. In various conditions, similar measurements were also done to study factors affecting the personal space perception in 14 men.
Mean values of bisected angles in percentage against range of motion were deviated from the middle points in the direction of the elbow extension, although there were large differences between the individuals. The deviation was smallest in the vertical. side of plane, and was larger in the horizontal plane than that in the vertical plane. The deviation was not so much affected by the various conditions.
It was suggested that the gain of the personal space perception is higher in the elbow extension than in the elbow flexion and its difference is larger in the horizontal plane than in vertical plane of the human elbow joint.