INTRAMUSCULAR LIPID CONTENT IN FEMALE ENDURANCE-TRAINED ELDERLY PERSONS BY IN VIVO ¹H-MR SPECTROSCPY / 体力科学

The aim of this study is the evaluation of intramyocellular (IMCL) and extramyocellular lipids (EMCL) in skeletal muscle in elderly female endurance-trained individuals. The subjects comprised endurance-trained elderly persons (END : n=7, age=66.1±2.0) and healthy elderly control subjects (CON : n=7, age=70.1±3.0). All subjects were female and matched by age and lower BMI. We quantified differences in IMCL and EMCL concentrations in the tibialis anterior (TA), soleus (SOL), and medial gastrocnemius (MG) muscles using ¹H-MR spectroscopy. The IMCL and EMCL contents in SOL and MG in END were significantly lower than those in CON (p<0.01). Total lipid content in SOL and MG was lower in END. The IMCL and EMCL contents in TA in END were slightly lower than those in CON. Water contents of all types of muscle in END were higher than those in CON. These results suggest that stored IMCL and EMCL in END are less than in CON.

CHARACTERISTICS OF INTRAMYOCELLULAR LIPID CONTENT IN SKELETAL MUSCLES OF OVERWEIGHT MEN AND ENDURANCE-TRAINED ATHLETES / 体力科学

This study used proton magnetic resonance spectroscopy (¹H-MRS) to investigate differences in muscle group specific intramyocellular lipid (IMCL) storage characteristics associated with elevated muscle lipid storage, and to determine whether IMCL content is associated with maximal aerobic capacity. Seven healthy men [untrained (UT)], four overweight (OW) and six endurance-trained (T) subjects volunteered for this study. Data were acquired, using ¹H-MRS, from the tibialis anterior (TA), medial gastrocnemius (MG) and soleus (SOL) muscles. The IMCL content in TA was approximately twice as high in T subjects than in UT and OW subjects. In MG, IMCL was higher in OW and T subjects compared with UT subjects. A linear relationship existed between the VO₂max and IMCL in TA and a curve of second-degree relationship between the VO₂max and IMCL in MG. These results suggest that elevated IMCL deposits in TA might reflect enhancement of aerobic capacity, whereas the IMCL accretion in MG might reflect not only aerobic capacity but also overweight and obese conditions in men.

<SUP>1</SUP>H-MRS STUDY ON GENDER DIFFERENCES IN INTRAMUSCULAR TRIGLYCERIDES IN HUMAN SKELETAL MUSCLE AND THEIR RELATION TO BODY FAT AND ENDURANCE CAPACITY / 体力科学

Gender differences were measured in the amount of intramyocellular triglyceride (IMCL) and extramyocellular triglyceride (EMCL) in skeletal muscles using<SUP>1</SUP>H-MR spectroscopy and their relation to body fat and peak VO<SUB>2</SUB>was studied. Fourteen apparently healthy subjects were separated into groups by gender. Both the male and female group subjects were selected according to similar ages and BMI (male: n=7, BMI=20.5±0.6 kg/m<SUP>2</SUP>, age=21.1±0.7 years, female: n=7, BMI=20.6±0.5 kg/m<SUP>2</SUP>, age=18.7±0.3 years) . We found a significant correlation between IMCL and EMCL in the soleus (SQL: p<0.01) and medial gastrocnemius (MG: p<0.01) muscles. IMCL values in SQL were significantly higher than IMCL values in MG and tibialis anterior muscle (TA) in both males and females in the order of SQL>MG>TA (p<0.01) .<BR>IMCL and EMCL values in MG and SQL among females were significantly higher (p<0.01) than their corresponding values in males. However, a gender difference in IMCL and EMCL values for TA was not found. There was no correlation between IMCL and EMCL values for each muscle and BMI ; but IMCL (r=0.63 in SQL) and EMCL (r=0.88 and r=0.73 in SQL, and MG, respectively; p< 0.01) values correlated significantly with percent FAT. There was no correlation between IMCL values for each muscle and peak VO<SUB>2</SUB>; but the EMCL values of SQL correlated quite negatively with peak VO<SUB>2</SUB> (r=-0.63, p<0.05) . These results suggest that there are gender differences in intramyocellular and extramyocellular triglyceride contents. Lipids were positively related to percent body fat in SQL and MG; EMCL values may have a negative effect on endurance capacity.

1H-MRS STUDY ON GENDER DIFFERENCES IN INTRAMUSCULAR TRIGLYCERIDES IN HUMAN SKELETAL MUSCLE AND THEIR RELATION TO BODY FAT AND ENDURANCE CAPACITY / 体力科学

Gender differences were measured in the amount of intramyocellular triglyceride (IMCL) and extramyocellular triglyceride (EMCL) in skeletal muscles using<SUP>1</SUP>H-MR spectroscopy and their relation to body fat and peak VO<SUB>2</SUB>was studied. Fourteen apparently healthy subjects were separated into groups by gender. Both the male and female group subjects were selected according to similar ages and BMI (male: n=7, BMI=20.5±0.6 kg/m<SUP>2</SUP>, age=21.1±0.7 years, female: n=7, BMI=20.6±0.5 kg/m<SUP>2</SUP>, age=18.7±0.3 years) . We found a significant correlation between IMCL and EMCL in the soleus (SQL: p<0.01) and medial gastrocnemius (MG: p<0.01) muscles. IMCL values in SQL were significantly higher than IMCL values in MG and tibialis anterior muscle (TA) in both males and females in the order of SQL>MG>TA (p<0.01) .<BR>IMCL and EMCL values in MG and SQL among females were significantly higher (p<0.01) than their corresponding values in males. However, a gender difference in IMCL and EMCL values for TA was not found. There was no correlation between IMCL and EMCL values for each muscle and BMI ; but IMCL (r=0.63 in SQL) and EMCL (r=0.88 and r=0.73 in SQL, and MG, respectively; p< 0.01) values correlated significantly with percent FAT. There was no correlation between IMCL values for each muscle and peak VO<SUB>2</SUB>; but the EMCL values of SQL correlated quite negatively with peak VO<SUB>2</SUB> (r=-0.63, p<0.05) . These results suggest that there are gender differences in intramyocellular and extramyocellular triglyceride contents. Lipids were positively related to percent body fat in SQL and MG; EMCL values may have a negative effect on endurance capacity.

MORPHOLOGICAL CHARACTERISTICS OF TRUNK MUSCLE GROUPS IN JAPANESE FEMALE ELITE JUDO ATHLETES / 体力科学

Using three-dimensional (3 D) imaging, we investigated the morphological characteristics of the M, latissiums dorsi (LD) and M, erector spinae (ES) of the dorsal trunk in judo athletes employing a computer graphics system on magnetic resonance imaging (MRI) . The subjects were five healthy untrained women (HUW) without lower back pain syndrome, and five Japanese female elite judo athletes (EJA) . There was no significant difference in height or weight between the HUW and EJA. Three-dimensional imaging of the LD and ES was reconstructed visually, based on MRI consecutive slice data taken from the first thoracic vertebra to the symphysis pubis along the trunk. Then the volume of the LD and ES was determined using a surface reconstruction algorithm.<BR>The morphological characteristics of the LD in the EJA appeared to indicate enlargment compared with those in the HUW, whereas the characteristics of the ES in both groups were similar. The volume of the LD was significantly different between the HUW (226.6±33.18 m<I>l</I>) and EJA (438.1±107.8 m<I>l</I>), whereas that of the ES showed no difference (HUW; 257.4±78.8 m<I>l</I>, EJA ; 284.0±74.82 m<I>l</I>) . In the EJA, but not in the HUW, there was a significant positive correlation between the volume of the LD and weight, and differences were noted between the two regression slopes. There was also a positive correlation between the volume of the ES and weight in both the HUW and EJA, which showed the same simple linear regression slope. These results suggest that the muscle hypertrophy evident in the LD, but not in the ES, is related to the effects of Judo training.

THREE DIMENSIONAL RECONSTRUCTION OF THIGH MUSCLE GROUPS BY COMPUTER GRAPHICS / 体力科学

The purpose of this study is to develop the non-invesive method for three dimensional analysis of knee extensor and knee flexor muscle groups of the thigh part in human subjects. Our system consisted of magnetic resonance imaging (MRI) to get cross-sectional images of muscle and a computer graphics system which reconstructs three dimensional image of each muscle. The subjects chosen for this study were four healthy male adults, aged from 21 to 30 years. MRI scan was carried out from head of the femur to the upper border of the patella along thigh. Three dimensional (3D) muscular image was reconstructed based on the data from MRI. Referring to the anatomic feature, contour information of knee extensor muscles (KEM) and knee flexor muscles (KFM) was identified on MRI and those muscles were reconstructed to 3 D images using the computer graphics system. This system also provided information on the quantitative volume and cross-sectional area (CSA) of each muscle.<BR>The structure of each muscle of KEM and KFM was displayed by a wireframe model or a surface model on the CRT. It was revealed that 3D muscular images of the surface model using coloring and shadowing were highly effective to understand their shapes and relative location of muscles. CSA and volume of KEM were 86.84±8.38cm<SUP>2</SUP>and 2044.25±168.28cm<SUP>3</SUP> and those of KFM were 38.48±5.90cm<SUP>2</SUP> and 751.95±50.56cm<SUP>3</SUP> respectively.<BR>These results indicate that not only the anatomical information but also the volume and maximum CSAs of KEM and KFM can be measured quantitatively by this method using three dimensional analysis.

CARDIO-VASCULAR FUNCTIONS AND PHYSICAL FITNESS OF PREADOLESCENTS AND ADOLESCENTS / 体力科学

Orthostatic Disregulation (OD, a kind of dysautonomia) is a syndrome which indicates disfunction of vessel contraction reflex during static standing. OD patients often show some symptoms of fainting, dizziness, headache and the like or syncope when they are holding orthostatic posture. OD is more recognized especially in preadolescence and adolescence periods (9-15 yrs.) . Brück & Oltmann (1957), Okuni (1958) etc, have reported details about OD.<BR>The purpose of this study was to obtain and discuss details relating to recent appearance of OD, physique, growth characteristics, cardio-vascular functions and physical fitness on OD children by the questionnaire method and some experiments.<BR>2, 227 children in elementary and junior high school in Yokohama and Kamakura cities as sub jectswere first screened by the questionnaire. And 165 subjects out of 2, 227 were at random selected for data on Schellong standing test, passive head-up tilt and distance running.<BR>The value of 9-29%, which was the ratio of false OD (+) appearance by the questionnaire method in this study, was recognized higher than the value of 5-20% by previous studies'. Physique on false OD (+) children was somewhat lean in comparison with the normal. And they had more height increase than the normal.<BR>In physical fitness, distance running, 50 m dash, broad jump, ball throw, chinning exercise and back pull-over tests, OD children were inferior than the normal.<BR>A concrete datum in syncope for standing was got in this study. When an OD child exhibited syncope, systolic blood pressure became 78 mmHg (rest 120-130 mmHg) and heart rate became 76 beats per minute (standing before syncope 100-110 beats per minute) . T wave in II, <SUB>a</SUB>V<SUB>F</SUB> and P wave in II, III (depression, negative waves etc.) of ECG varied from resting ECG. Judging from these data about ECG and blood pressure on standing test, passive head-up tilt, it was indicated that a reflex system of vessel contraction on OD child didn't work well, and that the heart of OD child was much stressed by gravity in orthostatic posture and changing posture than the normal.<BR>In addition, a fact was proven that false OD (+) children (39.1% boys and 48.2% girls) didn't like sports and physical activities comparing with the normal (16.4% boys and 23.5% girls), It was statistically significant. Therefore, it is estimated that there is a relationship between appearance of OD and physical activities in daily life.