Abstract: ObjectiveTo evaluate the effects of exercise training on bone histomorphometry of ovariectomized rats.Methods46 SD rats were randomly divided into the normal control group (group A), ovariectomized group (group B) , estrogen supplement group (group C) and exercise training group (group D). The rats of group A had a sham operation, while that of other groups was ovariectomized. 3 months after operation, the rats had been treated for 3 months. The rats of group C were given estradiol, and the rats of group D were trained by exercise. The tibia sections were studied by histomorphometric analysis.ResultsThe values of the trabeclar area, trabeclar area%, trabeclar perimeter and trabeclar number of group D were significantly higher than that of group B. The values of the trabeclar separation, osteoclast number/mm² and osteoclast number/mm of group D were the least in all groups, which had been ovariectomized. The values of the labeled perimeter % mineral apposition rate, bone formation rate of group D were superior to that of all groups.ConclusionThe exercise training can increase bone mass of ovariectomized rats, which had double effects of promoting bone formation and restraining bone absorption.

Key words: osteoporosis, bone histomorphometry, exercise training, ovariectomized rats