Significance. Resistance training has been considered the standard of care for increasing bone density in many populations. Cross-sectional studies have indicated that power-type training such as in gymnastics yields greater bone density in adolescents. However, longitudinal training studies have not confirmed this theory, especially in premenopausal women. It was the purpose of the present investigation to determine the effects of power and resistance training on bone mineral density (BMD) in a group of premenopausal women. Design. Nineteen women were randomly assigned to either a power or resistance training group. Power training consisted of jumping, skipping, and hopping activities. The resistance training group was prescribed 8-10 whole-body exercises at an intensity of 75% of their one-repetition maximum (1RM). Both groups trained for 48 weeks. Before the training began, all participants had their total-body, lumbar spine, and left femur BMD measured via DEXA. They also completed 1RM testing for the leg and chest press exercises as well as a maximal hand-grip dynamometer test. All participants performed the Margaria-Kalamen stair climb test to determine muscular power. A 2 X 2 repeated measures ANOVA was used to determine differences between the two groups for BMD, muscular strength, and muscular power. Results. No differences existed between the two groups for BMD at any site (Total-body F[1,17] = 2.13, p = .16; lumbar spine F[1,17] = 0.13, p = .73; femoral neck F[1,17] = 2.24, p = .15). No differences were found between the groups for changes in leg press strength (F[1,15] = 1.18, p = .29) or hand-grip strength (F[1,16] = 0.19, p = .67). A significant time effect existed for leg press strength for both groups (F[1] = 6.04, p = .027) and hand-grip strength (F[1] = 46.32, p <.0001). Significant differences in chest press strength existed between the two groups (F[1,15] = 9.44, p = .008). Those in the resistance training group increased chest press strength by 18.45% whereas participants in the power-training group increased by 5.21%. In conclusion, power and resistance training are effective means for maintaining BMD in premenopausal women. Power and resistance training also help to increase various measures of strength. Keyword(s): gender issues, research