Efficacy of resistance exercise on lumbar spine and femoral neck bone mineral density in premenopausal women: a meta-analysis of individual patient data.

BACKGROUND: Osteoporosis and osteopenia are major public health problems. The purpose of this study was to conduct an individual patient data (IPD) meta-analysis to examine the efficacy of resistance exercise on lumbar spine and femoral neck bone mineral density (BMD) in premenopausal women.
METHODS: Studies were retrieved via (1). computerized literature searches, (2). review of reference lists from previous studies, (3). hand searching selected journals, and (4). expert review of the reference list. Two x two analysis of covariance (ANCOVA) tests with repeated measures on one factor (time) and study as a covariate were used to analyze changes in BMD.
RESULTS: One hundred forty-three subjects (74 exercise, 69 control) were included in the analysis. Changes in lumbar spine BMD averaged 0.006 +/- 0.035 g/cm(2) (0.64 +/- 2.99%) in the exercise group and 0.008 +/- 0.091 g/cm(2) (0.74 +/- 7.58%) in the control group, and changes in femoral neck BMD averaged 0.005 +/- 0.031 g/cm(2) (0.46 +/- 3.10%) in the exercise group and 0.003 +/- 0.031 g/cm(2) (0.31 +/- 2.97%) in the control group. No statistically significant differences in lumbar spine or femoral neck BMD were found within or between the exercise and control groups (p > 0.05).
CONCLUSIONS: Based on existing evidence, our results do not support the efficacy of resistance exercise for increasing or maintaining lumbar spine and femoral neck BMD in premenopausal women.