ABSTRACT
<p><b>OBJECTIVE</b>The purpose of this study was to clarify the relationship between forearm bone mineral density (BMD), body mass index (BMI), and body composition focusing on body fat percentage (BF%) in Japanese females 18 to 40 years old.</p><p><b>METHODS</b>Subjects were 2,280 females 18-40 years old. Anthropometric measurements were taken, and a medical history was obtained by questionnaire, including age at the time of the study and age at menarche. BF% was measured by bioelectrical impedance analysis. Forearm BMD was measured using dual-energy X-ray absorptiometry (DXA). The correlations of BMD with BMI and BF% were analyzed using a structural equation model.</p><p><b>RESULTS</b>The standardized regression coefficients for the path from BMI to BMD and the path from BF% to BMD were 0.538 and -0.184 respectively. The squared multiple correlation of BMD was 0.146. In addition, the standardized regression coefficient for the path from BMI to BF% was 0.896.</p><p><b>CONCLUSION</b>The results showed a positive correlation between BMD and BMI and an inverse correlation between BMD and BF%. At the same time, it was noted that BF% increased with BMI. This indicated that BMD is dependant on BF% in subjects who have a similar BMI. Therefore, this study concluded that it is necessary to take body composition measurements into account when examining the relationship between BMI and BMD, especially in young females.</p>
ABSTRACT
Objective: The purpose of this study was to clarify the relationship between forearm bone mineral density (BMD), body mass index (BMI), and body composition focusing on body fat percentage (BF%) in Japanese females 18 to 40 years old. Methods: Subjects were 2,280 females 18–40 years old. Anthropometric measurements were taken, and a medical history was obtained by questionnaire, including age at the time of the study and age at menarche. BF% was measured by bioelectrical impedance analysis. Forearm BMD was measured using dual-energy X-ray absorptiometry (DXA). The correlations of BMD with BMI and BF% were analyzed using a structural equation model. Results: The standardized regression coefficients for the path from BMI to BMD and the path from BF% to BMD were 0.538 and −0.184 respectively. The squared multiple correlation of BMD was 0.146. In addition, the standardized regression coefficient for the path from BMI to BF% was 0.896. Conclusion: The results showed a positive correlation between BMD and BMI and an inverse correlation between BMD and BF%. At the same time, it was noted that BF% increased with BMI. This indicated that BMD is dependant on BF% in subjects who have a similar BMI. Therefore, this study concluded that it is necessary to take body composition measurements into account when examining the relationship between BMI and BMD, especially in young females.
Subject(s)
Body Mass Index , Body Composition , Bone DensityABSTRACT
To examine the work load of recent mechanized forestry work, energy expenditure, serum sarcoplasmic enzyme and urinary catecholamine were measured during engagement in the production of trees among twelve lumberjacks. Energy expenditure was relatively high in the works of debranching by a hatchet and hanging trees on carring wire cables. At least, the debranching work by a hatchet must be changed to more safety and lighter works. It was suggested that much more attention must be paid to the physiologic character of forestry work still now on the results of the changing pattern in serum sarcoplasmic enzyme and urinary catecholamine during these working process.
ABSTRACT
This study was designed to examine the relationship between exercise diuresis and running load, following seven types of running events by five male athletes, aged 19 to 25 years. None had a history of renal disease.<BR>Informed written consent was obtained from all subjects prior to the study.<BR>1. Compared to the resting levels, significant increases in the urinary volume were observed thirty minutes after performing a 400-meter dash, but not after the other exercises.<BR>2. The changes in creatinine concentration (30 min after exercise/after warm-up) were inversely proportional to the changes in urinary volume, indicating that exercise diuresis depends on the depressed reabsorption of water in the renal tubules.<BR>3. The absence of diuresis after 60 and 100-meter sprints, indicates that the phosphagen system is mainly employed for energy supply.<BR>4. The urinary volumes after 200, 300 and 400-meter dashs highly correlated with the changes in the excretion rate of pyruvate. This suggests that exercise diuresis is related to the lactic system in energy metabolism.<BR>5. The decreased excretion rate of creatinine after 800 and 1, 500-meter runs indicates that GFR is reduced by these exercises. Furthermore, the lactic energy system caused the diuretic effect. Thus, even though secretion of antidiuretic hormones is increased following exercise, their effectiveness is reduced by lactic oxygen deficit.
ABSTRACT
An experiment was carried with 15 males (60.2 years old on the average) and 12 females (43.3 years old on the average) who had made it a rule to run regularly for exercise in daily life. The females were before the climacteric stage. Its purpose was to study the serum cholesterol fraction in relation to food intake and distance, duration, and speed of running for exercise.<BR>The following results were obtained.<BR>1) The composite variable of serum lipid synthesis tended to be affected more distinctly by the group with food intake as indicator than by the group with locomotion as indicator. It seemed to be influenced primarily by the amount of food intake to a remarkable extent, and secondarily by the group with locomotion as indicator. In this group an increase in consumption of energy with the practice of running exercises participated in bringing about such influence.<BR>2) It was suggested that great care should be taken for food intake in performing running exercises as a habit, taking energy consumed by running into consideration.
ABSTRACT
For revealing the post exercise proteinuria, the variation of leucine aminopeptidase (LAP) and γ-glutamyltranspeptidase (γ-GTP) activities were observed to know the fluctuation of the substances excreted in the urine and the composition of the urinary protein in 4 college athletes aging from 19 to 21 years before and after 10-mile road race.<BR>The results obtained are as follows:<BR>1) During the race and in the early stage of recovery the excretion of creatinine, uric acid, and urea-nitrogen decreased, and in this term clearance in the kidney reduced. More than 60 minutes after the end of the road race, the excretion of these substances returned to the level before the race.<BR>2) The urinary pH value began to increase just after the race, became alkaline at pH more than 7 and less than 8 in all the subjects 30 to 60 minutes after the race, 90 to 120 minutes after the race it returned to level obtained before the race.<BR>3) In the term when the excretion of the substances decreased, as described in the above 1), protein was much excreted, and it gradually decreased in the urine collected 60 to 90 minutes and later after the race, but the level of the excreted protein was still higher than that obtained before the race.<BR>4) The Albumin/Globulin ratio of the urinary protein was low at rest, but in the early stage of recovery it was higher than 1, but in the later stage of recovery it decreased.<BR>5) LAP and γ-GTP activities were also high in the term when protein was much excreted, but gradually decreased following the progress of recovery. LAP activity in the urine collected 120 to 150 minutes after the race recovered nearly to the level before the race, but γ-GTP remained still at a rather high level, and indicated the difference in the composition of the post exercise proteinuria.<BR>6) It was estimated that the post exercise proteinuria would include not only the leaked plasma component caused by increase of the permeability but also some part derived from the renal tissue.
ABSTRACT
Fourteen female handball players who were candidates for Olympic representative team were asked to run 12 minutes, and the relationship between the variation of the urinary components and the variations of the running speed and the heart beats was researched.<BR>The obtained results in short are in the following:<BR>1) The covered distance of the 12-minute running was from 2, 385 meters to 3, 050 meters, and the average was 2, 830±196.6 meters.<BR>2) The heart beat rate quickly recovered for about 5 minutes after running, and then gradually reduced; after 30 minutes the rate was considerably higher than the level before the running in many cases.<BR>3) The urinary volume was obviously less after the running than that before it.<BR>4) The 1-hour after urine including the running time contained much pyruvates and lactates exhausted therein, and then the excretion amount reduced to the previous level. The ratios of Pyruvic acid/Creatinine and Lactic acid/Creatinine showed similar tendencies. The ratio of Pyruvic acid/Creatinine before the running against that after the running showed positive correlation with the running speed more than 230m/min., but showed a negative correlation clearly with the recovering rate of the heart beat after 30 minutes being higher than 60%. It suggests that the excretion of urinary pyruvate increase with more anaerobic factors for energy production under the conditions of the higher speed running and the larger oxygen debt.<BR>5) The urinary citrate obviously decreased just after the running, but in recovered considerably in the urine obtained after 2 hours. The ratio of Citric acid/Creatinine was low just after the running. The variations appears not to be simply due to the reduction of renal clearance.<BR>6) The urinary creatinine tended to reduce in the urine obtained 1-hour after the running, and particularly with the urinary pyruvate more than 50μg/ml there was observed clear negative correlation with creatinine which showed lower concentration with more anaerobic factors; it suggests some reduction of renal clearance.