Differences in the effects of BMI on bone microstructure between loaded and unloaded bones assessed by HR-pQCT in Japanese postmenopausal women

Objectives@#The relationship between weight-related load and bone mineral density (BMD)/bone microstructure under normal load conditions using high-resolution peripheral quantitative computed tomography (HR-pQCT) remains unconfirmed. The study aims to investigate the differences in effect of body mass index (BMI) on BMD/bone microstructure of loaded and unloaded bones, respectively, in Japanese postmenopausal women. @*Methods@#Fifty-seven postmenopausal women underwent HR-pQCT on the tibia and radius. Correlation analysis, principal component (PC) analysis, and hierarchical multiple regression were performed to examine the relationship between BMI and HR-pQCT parameters. @*Results@#Several microstructural parameters of the tibia and radius correlated with BMI through a simple correlation analysis, and these relationships remained unchanged even with an age-adjusted partial correlation analysis. PC analysis was conducted using seven bone microstructure parameters. The first PC (PC1) reflected all parameters of trabecular and cortical bone microstructures, except for cortical porosity, whereas the second PC (PC2) reflected only cortical bone microstructure. Hierarchical multiple regression analysis indicated that BMI was more strongly related to BMD/bone microstructure in the tibia than in the radius. Furthermore, BMI was associated with trabecular/cortical BMD, and PC1 (not PC2) of the tibia and radius. Thus, BMI was strongly related to the trabecular bone microstructure rather than the cortical bone microstructure. @*Conclusions@#Our data confirmed that BMI is associated with volumetric BMD and trabecular bone microstructure parameters in the tibia and radius. However, although BMI may be more related to HRpQCT parameters in the tibia than in the radius, the magnitude of association is modest.

Differences in the effects of BMI on bone microstructure between loaded and unloaded bones assessed by HR-pQCT in Japanese postmenopausal women

Objectives@#The relationship between weight-related load and bone mineral density (BMD)/bone microstructure under normal load conditions using high-resolution peripheral quantitative computed tomography (HR-pQCT) remains unconfirmed. The study aims to investigate the differences in effect of body mass index (BMI) on BMD/bone microstructure of loaded and unloaded bones, respectively, in Japanese postmenopausal women. @*Methods@#Fifty-seven postmenopausal women underwent HR-pQCT on the tibia and radius. Correlation analysis, principal component (PC) analysis, and hierarchical multiple regression were performed to examine the relationship between BMI and HR-pQCT parameters. @*Results@#Several microstructural parameters of the tibia and radius correlated with BMI through a simple correlation analysis, and these relationships remained unchanged even with an age-adjusted partial correlation analysis. PC analysis was conducted using seven bone microstructure parameters. The first PC (PC1) reflected all parameters of trabecular and cortical bone microstructures, except for cortical porosity, whereas the second PC (PC2) reflected only cortical bone microstructure. Hierarchical multiple regression analysis indicated that BMI was more strongly related to BMD/bone microstructure in the tibia than in the radius. Furthermore, BMI was associated with trabecular/cortical BMD, and PC1 (not PC2) of the tibia and radius. Thus, BMI was strongly related to the trabecular bone microstructure rather than the cortical bone microstructure. @*Conclusions@#Our data confirmed that BMI is associated with volumetric BMD and trabecular bone microstructure parameters in the tibia and radius. However, although BMI may be more related to HRpQCT parameters in the tibia than in the radius, the magnitude of association is modest.

Exercise physical characteristics and laboratory findings in Japanese elite Judo athletes / 体力科学

A study was performed to evaluate the physical exercise characteristics of 29 Japanese elite judo athletes by treadmill exercise test. Functional aerobic impairment (FAI), heart rate impairment (HRI) and peripheral circulatory impairment (PCI) in the judo athletes were not significantly different from those of normal sedentary subjects. However, myocardial aerobic impairment (MAI) was lower than in normal sedentary subjects. %VO<SUB>2</SUB>max at the anaerobic threshold (AT) was 57.5±3.3% in male, and 57.0±4.3% in female judo athletes. %HRmax at AT was 72.4±3.8% in males, and 75.2±5.3% in females.<BR>These findings suggest that functional aerobic capacity and peripheral circulatory function in Japanese elite judo athletes are not significantly different from those of normal sedentary subjects, but that judo athletes have high left ventricular function.<BR>The blood biochemical profile and urinalysis date revealed that values of muscle injury enzymes, plasma uric acid and cholesterol were increased with relatively high freqency in elite judo athletes. Similar data were also obtained in individuals with suspected diabetic nephropathy and rhabdomyolysis.