TABLE 4.

Multiple linear stepwise regression analysis of the explanatory variables for changes in femoral neck BMD, total body BMD, and tibia cortical thickness¹

Variable	R2	β	P
Femoral neck BMD
Body weight	0.15	0.32	0.01
25(OH)D	0.10	0.42	0.03
Total body BMD
Fat-free soft tissue	0.19	0.44	0.05
Cortical thickness
Free estradiol	0.14	−0.36	0.02

¹Analysis was done for change in variables over 6 mo (n = 38). The final model did not include variables that did not reach significance (physical activity level, total body fat, parathyroid hormone, and total and free testosterone). A separate analysis was conducted for each individual group (not shown in the table). In the WL group, there was a trend for the change in fat-free soft tissue to explain 18% of the change in total body BMD (β = 0.42, P = 0.06), and there were no other significant explanatory variables for the femoral neck BMD or cortical thickness. There were no explanatory variables for the WM group. BMD, bone mineral density; 25(OH)D, 25-hydroxyvitamin D.