ABSTRACT
<p><b>OBJECTIVES</b>To clarify the relationship between bone mineral density (BMD) and body composition in Japanese women aged 18-40 years with low forearm BMD.</p><p><b>METHODS</b>The subjects were Japanese 199 women who had been selected for inclusion in the study based on a low forearm BMD determined at the Annual Women's Health Examination. The subjects' mean (+/- standard deviation) age, body height, body weight, and body mass index (BMI) were 33.5 (+/-4.3) years, 158.1 (+/-5.1) cm, 49.6 (+/-5.7) kg, and 19.8 (+/-2.1), respectively. The BMD of the lumbar spine, total body, and left arm were measured using dual-energy X-ray absorptiometry (DXA). Fat mass (FM), bone-free lean tissue mass (LTM), and body fat percentage (BF%) were measured simultaneously with DXA.</p><p><b>RESULTS</b>In the structural equation model, the standardized regression weights for the path from BMI to BMD of all sites were 0.273-0.434. Conversely, the BF% to BMD of the total body and left arm were -0.192 and -0.296, respectively. In multiple regression analysis, the FM index (FMI) was significantly associated with the BMD of the lumbar spine as a weight-bearing site. The LTM index (LTMI) was significantly associated with the BMD of the total body and left arm as a non-weight-bearing site.</p><p><b>CONCLUSIONS</b>Young females with low forearm BMD had low body weight and BMI. Thinness was shown to be a risk factor for low BMD, in accordance with results reported elsewhere. A gain in body weight may have the effect of increasing BMD, but our results suggest that to increase BMD, the gain in body weight must include increases in LTM, and not FM alone.</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
<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
The objective of this study was to examine the association between body mass index (BMI) and blood pressure. Two sets of cross-sectional data were obtained from annual health examinations for adults aged 40 years and over (n=1,327 in 1993; n=1,302 in 2000) in Tsunagi area of Kumamoto Prefecture, Japan. BMI was associated with mean blood pressure and with prevalence of hypertension both in 1993 and 2000. The association was independent of age, smoking status and alcohol consumption. A significant increase in risk of hypertension was found in most categories of BMI 25.0 and above, and a greater than three fold increase in those with BMI of 27 and above compared with those with BMI of 18.5−22.9. Although mean blood pressure and prevalence of hypertension sharply decreased in 2000 compared with that in 1993, BMI was positively and independently associated with increased blood pressure.
Subject(s)
Body Mass Index , Blood PressureABSTRACT
The objective of this study was to examine the association between body mass index (BMI) and blood pressure. Two sets of cross-sectional data were obtained from annual health examinations for adults aged 40 years and over (n=1,327 in 1993; n=1,302 in 2000) in Tsunagi area of Kumamoto Prefecture, Japan. BMI was associated with mean blood pressure and with prevalence of hypertension both in 1993 and 2000. The association was independent of age, smoking status and alcohol consumption. A significant increase in risk of hypertension was found in most categories of BMI 25.0 and above, and a greater than three fold increase in those with BMI of 27 and above compared with those with BMI of 18.5-22.9. Although mean blood pressure and prevalence of hypertension sharply decreased in 2000 compared with that in 1993, BMI was positively and independently associated with increased blood pressure.
ABSTRACT
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.