Osteoporosis affects many postmenopausal women and represents an economic burden. The purpose of the study was to observe the effects of a 1-year strength program on the bone mass at the level of the femur. Twenty-nine women were included in the randomized study, being divided into an exercise group (56±2.9 years old, n = 20) and a control group (56.4±2.1, n = 19). After 12 months of participation in the strength program (twice a week, using intensities of 70% of 1RM and 50% of 1RM) the exercise group showed statistically significant increases in all areas of interest of the femur as follows: femoral neck (+2.05%, p = .001, η_p^2 = .45), trochanteric area (+3.80%, p < .001, η_p^2 = .75), intertrochanteric area (+0.97%, p = .013, η_p^2 = .37), Ward's triangle (+1.77%, p = .023, η_p^2 = .24) and femur's total bone mineral density (+1.97%, p < .001, η_p^2 = .51). After 12 months, at the femoral neck region, the increase in bone density was 7.3 times higher compared to the control group (p = .01, F(1, 36) = 6.62, η_p^2 = .15, 95% CI [0.002, 0.020], at the trochanteric area the increase was 8 times higer compared to the control group (p < .001, F (1, 36) = 16.48, η_p^2 = .31, 95% CI [0.009, 0.027] and at the total level of the femur, the increase in bone density was 8.6 times higher compared to the control group (p = .01, F (1, 36) = 7.09, η_p^2 = .17, 95% CI [0.003, 0.024]. In conclusion, alternating the intensities of 70% of a maximum repetition with those of 50% of a maximum repetition within the same set of 12 repetitions, bone mineral density at the level of the femur can undergo improvements.