1.STUDY OF CHARACTERISTICS OF WAVING MOVEMENTS IN UPPER EXTREMITIES
KUNIATSU NAGAMI ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1977;26(3):103-113
The purpose of this study is to investigate the characteristics of the waving move-ments of upper extremities in gymnastics.
First, a photograph of the waving movements of a trained female was taken with 16 mm cinecamera. The following results energed from the motion analysis
1. The elbow joint moved within a range of about 10 degrees in the horizontal direction, and within a range of 60 to 70 degrees in the vertical direcion.
Therefore, the width of movement was remarkably extensive in the vertical direction. Accordingly, four trained and four untrained females who were to discuss the above characteristics, the movements were recorded using an electrogoniogram for the elbow joint, and an electromyogram for the m. deltoideus, m. triceps brachii and m. biceps brachii, respectively.
The electrogoniogram readings were analysed as follows
Calculations were made of the time of extension (TE) and flexion (TF), and the angle of extension (θE) and flexion (θF) of the elbow joint
2. There did not appear to be a significant relationship between θE and θF in either group.
3. In the trained group, TE was longer than TF. However, with the untrained group, TE and TF were much the same. TE/θE and TF/θF of the elbow joint were calculated, indicating the time taken for movement through one degree.
4. It was recognized as significant difference that the trained group moved the elbow joint more slowly than the untrained group.
From the present studied, the properties of the muscular contraction which was activated by the waving movement, were considered to be different for the two groups.
Reaction time of the m. tricepts brachii of all subjects was measured in the various conditions. Reaction time of muscular contraction (CR) was rapidly extended the forearm to horizontal level, and muscular relaxation with (PR) and without (AR) contralateral muscular contraction (m. biceps brachii) was the opposite movement to CR.
5. Comparison between CR and AR : In the trained group, AR was faster than CR, but in the untrained group, the opposite was the case. However, no significant difference was recognized
6. Comparison between CR and PR, AR and PR : For most members of the trained group, PR was significantly faster than CR and AR, but this was not so with the untrained subjects.
Therefore, the differences for each person were considered to be dependent on inhibition in the nervous system. The characteristics may be connected with the activity of the inhibitory system
2.SIGNIFICANCE AND DIFFERENCE OF FLEXOR MUSCULAR RELAXATIONS WITH AND WITHOUT EXTENSOR MUSCULAR CONTRACTION IN ARM MUSCLES
KUNIATSU NAGAMI ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1979;28(2):112-121
In the present report, significances of voluntary muscular relaxations were studied. Pattern of relaxation in elbow flexor muscles was examined in two conditions, with and without relaxation of contralateral muscles (Active Relaxation : AR, Passive Relaxation : PR, respectively) .
EMG patterns of biceps were obtained in various experimental conditions to investigate characteristics of each muscular relaxations. Arm flexor strength was exerted with saw-tooth and square forms produced by Low Frequency Generator, and in other case the strength was voluntarily exerted as fast as possible.
Muscular relaxation time was determined by the difference between begining of tension decrease and vanishing point of biceps spike discharge.
The results were ;
1) PR was faster than AR, but both relaxation times were prolonged following the increment of initial tension. There were no significant differences in the times between left and right arms, and between supine and prone positions of the forearm. Relaxation time in the square form muscular exertion was the fastest in AR.
2) Quickness of the biceps relaxation in PR was significantly correlated with the velocity of extensor muscular contraction. (r=0.41)
3) However, a transient excess tension development over the initial tension was observed at the initiation of relaxation in both conditions (less than 1 kg and 100 msec in most cases) . Both the excess tension produced and its duration were greater when the initial tension was higher. The rate of rise (g/msec) in PR was higher than AR.
These results suggested that each muscular relaxation in this study was conducted by different inhibitory systems. The inhibitory system in Active Relaxation might be localized in higher level of the central nervous system than that of Passive Relaxation
3.EFFECT OF DENERVATION ON SKELETAL MUSCLE DEVELOPMENT OF POSTNATAL RATS
MITSUO NARUSAWA ; TOSHITADA YOSHIOKA ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1982;31(3):196-204
At early stage of rats after birth, each innervation muscle fiber is supplied by two or more motor axones which converge on to a single end-plate and become one single axon in future. And undifferentiated cells frequently observed in the interspace among muscle fibers. About 70% of number of total muscle fibers in soleus developed in 21st day after birth.
Effect of denervation on the process of muscle development is studied in this paper. Left saiatic nerve of the rats was cut at 1st, 7th, 14th, and 21st day after birth. After 2 and 4 weeks, soleus and extensor digitorum longus muscle of both legs were dissected. Right side muscles used as control. Each muscle was cut transversely at the muscle belly and quickly frozen. Frozen sections, about 10 pm thick, were stained with hematoxylin eosin and other histochemical agents. Many optical micrographs of 50 or 100 magnifications were obtained from one cross-sectioned specimen. Number of muscle fibers were calculated on combined micrographs.
The results were as follows : (1) At 2 and 4 weeks after denervation, percentage loss of muscle weight was always higher than the loss of muscle cross-sectional area. At 2 and 4 weeks after denervation, the muscle weights were reduced to 45-80% and 70-90% of the control. And denervation muscle weights highly reduced in order that of let, 7th, , 14th and 21st eray rate after birth (2) At 2 and 4 weeks after denervation, number of soleus muscle fibers were reduced to 20-50% and 50-70% of the control. (3) At 2 weeks after denervation the reduction of number of muscle fibers of 1st day old rats was smaller than that of 7 days old rats.
First and second results suggest that muscle development is certainly influenced by neurotrophic foctors. But from third result it is possible to think that muscle development at 1st day old rats is influenced by inheritfactors of the muscle.
4.Effects of partial denervation on the differentiation of muscle fiber types in the rat.
MITSUO NARUSAWA ; TOSHITADA YOSHIOKA ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1984;33(3):130-141
In this study, the rats were subjected to a partial denervation of the soleus muscle at the age of three weeks. After this, histochemical investigations were carried out to establish what kind of changes had occurred in the differentiation of the muscle fiber type as a result of this partial drop in muscle activity.
The partial denervation was performed on the sinistral rat's soleus muscle, roughly 20% of the nerve bundles. After this, the dextral soleus muscle was used as the contralateral control muscle and excised after two, four and eight weeks, respectively. Frozen sections of muscle were stained with HE and myosin ATPase. The cross sectioned specimen were used for determining the muscle fiber count and type II fiber count.
The results thus obtained show that, compared with the contralateral control muscle, the partially denervated muscle have an approximately 5% reduced muscle fiber count two and four weeks after the partial denervation, and the type II fiber count, too, decreased to approximately 2/3 and 1/5, respectively. However, at eight weeks post-operatively, the muscle fiber count for the partially denervated muscle become almost the same as that for the contralateral control muscle, while the type II fiber count has, at this stage, recovered to approximately half its contralateral control muscle.
From these observations, it had been concluded that the reduction in muscle activity due to its partial denervation continues to act as a causal factor in the fiber type transformation untill four weeks after the partial denervation. The muscles evaluted eight weeks postoperatively showed an increase in type II fiber over the count determined four weeks after the partial denervation, and the muscle fiber count had also developed at eight weeks to value identical to that of the contralateral control muscles. Therefore, it has been concluded that the fiber type transformation in the muscle eight weeks after partial denervation is attributable to the reinnervation of the denervated muscle fibers due to the remaining intact motoneurons and to the resulting changes in motor unit size.
5.Changes in the numbers of proliferating cells and muscle fibers in growing rat skeletal muscle.
SHUICHI UCHIYAMA ; TETSURO TAMAKI ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1993;42(2):130-137
Changes in the numbers of muscle fibers and proliferating cells detected by immunohistochemistry were studied in correlation with various growth parameters including changes in body weight, lower hindlimb length, muscle length, muscle weight and age in Wistar-strain rats at various developmental stages. The total fiber number in plantaris (PLA) muscles increased gradually between 2 weeks and 10 weeks of age (about 300g body weight), and then remained constant between 10, 000 and 11, 000 these after. In contrast, proliferating cells labeled by bromodeoxyuridine decreased gradually during the same period, and were hardly evident after 10 weeks. In the growth curves for the body weight, lower hindlimb length, muscle weight, and the length of the extensor digitorum longus (EDL) muscle, turning points were observed at 10 weeks (300 g body weight), respectively, suggesting that the turning point between growth in length and growth in width occurred at this point. Furthermore, the growth curves for the body weight and PLA muscle weight were correlated between 2 and 20 weeks, including the turning point. Therefore it is suggested that the development of muscle weight from 2 to 10 weeks depends mainly on the increment of fiber number (hyperplasia), whereas development after 10 weeks depends on the increment of individual fiber diameter (hypertrophy), in relation to the tendency for an increase in fiber number and a decrease in proliferating cells. These results indicate that maturation of skeletal muscle in male Wistar rats occurs at 10 weeks of age and a body weight of 300g. Accordingly, these facts should be considered when investigating muscle hypertrophy or hyperplasia.
6.METABOLIC ADAPTATIONS TO ENDURANCE TRAINING MONITORED BY BLOOD LACTATE CONCENTRATION IN MALE RATS
NAN ZHANG ; TAMOTSU TERAO ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 1995;44(1):127-135
We studied the effects of 8 weeks of endurance training on the metabolism in rats. Different treadmill speeds, which corresponded to 2 mM and 4 mM blood lactate concentrations, were used to vary the intensity of the endurance training. After 8 weeks of training, blood lactate concentrations had decreased whereas β-hydroxyacyl-CoA dehydrogenase activity had increased. Citrate synthase activity in the m.extensor digitorum longus (EDL), and m.tibialis anterior (TA) of rats trained at the 4 mM level was higher than in rats trained at the 2 mM level and in control rats. In addition, muscle glycogen content in the hindlimb was higher and muscle TG content in the m.soleus (SOL) was lower in trained rats. These results suggest that training at 4 mM level significantly increases muscle mitochondrial oxidative capacity, and fatty acids are utilized as an energy source regardless of exercise intensity at least in the 2 to 4 mM intensity range. We concludes that an intensity of 4 mM is a useful level with which to elucidate the various adaptations to endurance training.
7.Magnetic Resonance Imaging as an Index of Muscle Activation During Uphill and Downhill Running.
KAZUYA YASHIRO ; TOMOHO ISHII ; KAZUHIRO SUZUKAWA ; HIROSHI KIYOTA ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 2001;50(2):201-210
The purpose of this study was to investigate the usage of the lower limb muscles (quadriceps femoris : QF, m. vastus lateralis : VL, m. rectus lemons : RF, m. vastus medialis : VM, m. vastus intermidialis : VI, hamstring : HM, m. gastrocnemius : UN, tihialis anterior : TA) and blood lactic acid concentration during uphill ( : UR +5 %) and downhill running ( : DR - 5 %) . We used magnetic resonance imaging (MRI) as one of the major indices. Seven healthy male volunteers participated in this study. T 2-weighted MR imaging, muscle surface temperature and blood lactic acid concentration were measured before and after UR and DR. In MRI imaging, the T2 value was defined as the area in which a high signal appeared after exercise.
The value of the blood lactic acid concentration of UR was higher than that of DR (p<0.001) . After DR, the muscle surface temperature of RF was lower in comparison with other muscles (p< 0.05) . After UR, the T2 value of RF (p<0.05), HM (p<0.01) and UN (p<0.05) was higher than after DR exercise. During UR, a positive correlation (r=0.818) existed between the T 2 value of GN and blood lactic acid concentration (P<0.05) . During DR, a positive correlation (r=0.739) was also observed between the T 2 value of QF and blood lactic acid concentration (p<0.05) .
From these results, we conclude that (1) the pattern of usage of lower limb muscles differs during UR and DR, (2) the most mobilized muscles in the lower limbs for UR are GN and HM, and (3) the most mobilized muscle in the lower limbs for DR is QF, respectively. These findings show that different exercises affect the blood lactic acid concentration differently.
8.DOPPLER ECHOCARDIOGRAPHIC ANALYSIS OF EXERCISE-INDUCED ADAPTATION OF LEFT VENTRICULAR MUSCLE MASS AND ARTERIAL VESSELS IN YOUNG COMPETITIVE ATHLETES OF VARIOUS SPORTS
HEFENG DAI ; TATEHIRO TOYOSHIMA ; HIROSHI KIYOTA ; MAKOTO YAMATO ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 2002;51(5):457-463
The purpose of this study was to analyze morphological and functional changes in the left ventricular muscle mass and vessel diameters of the arteries in young competitive athletes of various sports and evaluate the correlation between the heart and arterial vessel under the training environment in this latter half of the growth period. The subjects were 51 male college student athletes (mean age, 19.6±0.4 years) of 6 competitive sports (archery, weight lifting, swimming, short-distance races, middle-distance races, and long-distance races) . The diameters of the right and left common carotid arteries, right and left radial arteries, right and left foot dorsal arteries, and the aorta and the left ventricular muscle mass (LVM) were measured by Doppler echocardiography. To minimize the influences of the physique and body weight associated with growth and sport types, all data obtained by measurement were corrected by body surface area. The sum of the diameters of all the above arteries (total arterial diameter : TAD) was obtained to evaluate its correlation with the left ventricular muscle mass. The diameter of the foot dorsal artery was significantly higher in the long-distance runners than in the sprinters (P<0.05) . The diameter of the radial artery according to the 6 types of sport was the highest for weight lifting, followed in order by archery, longdistance races, middle-distance races, swimming, and short-distance races, showing a significant difference between weight lifting and short-distance races (P<0.05 ) . TAD was high for generalized endurance sports and correlated with the left ventricular muscle mass (r=0.893) . Thus, the arterial diameters significantly differed among competitive sports and were particularly increased for endurance exercise. The diameters of the local arteries used for local exercise were also increased. When TAD as a new parameter and its ratio per body surface area were calculated, there was a high correlation between the heart (left ventricular muscle mass) and the arterial diameter. These results suggest that exercise adaptation can he evaluated in the arterial system in svstemic circulation as well as the nervous and muscular systems.
9.Penetration of Different Kinds of Peptides or Collagen Through the Intestinal Membrane.
KAZUHIRO SUZUKAWA ; HIROMITSU TANI ; HIROKAZU OSANAI ; MINAYUKI SHIRATO ; SHOICHI NAKANO
Japanese Journal of Physical Fitness and Sports Medicine 2003;52(1):99-110
Penetration of different kinds of peptides or collagen peptide through the intestinal membrane was studied in two experiments using anin vitrorat everted intestine penetration model. In Study 1, twelve 11-wk-old rats (Wistar strain) were randomly divided into two groups and penetration of whey peptide (n=6) and soy peptide (n=6) through the intestinal membrane was compared. In Study 2, fourteen 11-wk-old rats (Wistar strain) were divided into a control group (n=7) and a training group (treadmill running at a speed of 20-35 m/min for 15 mm day, 5 days wk for 4 wk n=7), and penetration of collagen peptide through the intestinal membrane was investigated in the two groups. In Study 1, the quantity of whey peptide that penetrated through the intestinal membrane was significantly greater than that of soy peptide (P<0.01) . In Study 2, body weight was significantly lower in the training group than in the control group except during 12 and 12.5 wk of age (13.5 wk ; P<0.01, others; P<0.05) . The weights of heart, kidney, and spleen were significantly increased, and the weight of fat was significantly decreased in the training group compared to the control group (P<0.05, P<0.05, P<0.01, P<0.05, respectively) . In both groups, a portion of collagen peptide penetrated through the intestinal membrane; but there was no significant difference in quantity between the two groups. In conclusion, the inhibition of weight gain in the training group was possibly caused by decreased feeding from lack of appetite with enforced exercise. These findings suggest that whey peptide penetrated through the intestinal membrane in greater quantities than soy peptide, and collagen peptide is not affected by enforced exercise.
10.RELATION BETWEEN BODY COMPOSITION AND PHYSICAL ATHLETIC PERFORMANCE OF LONG DISTANCE RELAY RUNNERS PRODUCED BY A FOUR WEEK WEIGHT LOSS PROGRAM
TATEHIRO TOYOSHIMA ; KAORI INOSHITA ; TOMOHO ISHII ; SHOICHI NAKANO ; TAKASHI ITO
Japanese Journal of Physical Fitness and Sports Medicine 2005;54(1):87-97
The purpose of this study was to examine the relation between body composition and athletic performance of long distance relay runners in a four week weight reduction program. Six male collegiate runners, aged 19.0 ± 0.9 years, participated in this study. Body water content and fat free mass (FFM) were measured by bioelectrical impedance spectroscopy.The weight loss by 4.1% of the initial body weight consisted of decreases in FFM and fat mass (54% and 46% respectively). Percentage of body fat did not change significantly by the end of the fourth week. The total body water (TBW) loss comprised of intracellular water (ICW) and extracellular water (ECW) at the end of the fourth week, and TBW loss and FFM loss were nearly the same values. Isokinetic muscular strength of right thigh, maximal oxygen intake (VO2max) and total treadmill running time (maximal workout time) measured did not show any significant change. These results indicate (1) half of the weight loss consisted of decrease in FFM, (2) TBW loss was due to the reduction of ICW and ECW, (3) the content of FFM loss was considered to be body water, and (4) there was no impact on muscular strength of right thigh, VO2max or maximal workout time.