0bjeclive　To　examine　the　innuence　of　daily　physical　activities,,　especially　exercise.　on　bone　mineral　densily　in　women　receiving　treatment　for　postmenopausal　osteoporosis.　
Methods　Physical　strength　(exercise　tolerance,　aerobic　capacity,　and　muscle　strength)　and　daily　physical　activity　levels　(energy　consumption　per　day,　kcal/day)　were　evaluated　in　39　middle-aged　women　with　postmenopausal　osteoporosis　or　osteopenia　who　were　receiving　hormone　replacement　therapy　(HRT).　The　subjects　were　divided　into　three　groups　on　the　basis　of　the　percent　change　in　the　bone　mineral　density　of　the　second　to　fourth　lumbar　vertebrae　(%BMD)　during　6　months　of　HRT:　the　responder　group,　in　which　the　bone　mineraI　density　increased　by　more　than　2%;the　unchanged　group,　in　which　the　change　in　bone　mineral　density　was　within　±2%;　and　the　non-responder　group.　in　which　the　bone　mineral　density　decreased　by　more　than　2%. 
Resuits　Physical　strength　did　not　differ　significantly　among　the　three　groups.　Physical　activity　levels　in terms　of　daily　energy　consumption　and　weight-corrected　energy　consumption　were　signlficanUy　higher　in　the　responder　group　than　in　the　unchanged　group　and　non　responder　group. 
Conclusions　Maintaining　moderate　or　higher　levels　of　physical　activity　helps　to　increase　bone　mineral
density　in　women　receiving　HRT.

原著