***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: PURPOSE The purpose of this study was to determine the effects of 6 months of whole-body resistive training ( RT ) on total and regional bone mineral density ( BMD ) and bone mineral content ( BMC ) by age and gender in young and older men and women . METHODS Younger men ( n=10 ) and women ( n=7 ) aged 20 - 29 years ( 25+/-1 years ) and older men ( n=10 ) and women ( n=10 ) aged 65 - 74 years ( 69+/-1 years ) participated in 6 months of progressive whole-body RT .  Upper- and lower-body strength was assessed by the one repetition maximum ( 1RM ) test , and total body fat , lean tissue mass , femoral neck BMD , Ward 's triangle BMD , greater trochanter BMD , total-body BMD , and L2-L4 spine BMD were determined by dual-energy X-ray absorptiometry before and after 6 months of RT . RESULTS Percent body fat decreased only in the young men ( P<0.05 ) . Lean tissue mass increased after training in young men and women and older men ( P<0.05 ) but did not change significantly in older women . Upper- and lower-body 1RM strength increased in all groups ( P<0.01 ) . Overall , there was a significant increase in BMD at the femoral neck , ward 's triangle and greater trochanter BMD , as well as total body BMC and leg BMC ( P<0.05 ) . Total-body BMD and L2-L4 spine BMD did not change with RT . There were no gender differences in the training response between men and women for any of the BMD regions and no age differences in the training response , except for a trend between young and older subjects for femoral neck ( P<0.08 ) . CONCLUSION A 6-month RT program increases muscle mass and improves BMD of the femoral region in young and healthy older men and women as a group , with a trend for this to be greater in young subjects STUDY OBJECTIVE To assess the effect of weight-bearing exercise training and subsequent detraining on lumbar bone mineral content in postmenopausal women . DESIGN Non-r and omized , controlled , short-term ( 9 months ) trial and long-term ( 22 months ) exercise training and detraining ( 13 months ) . SETTING Section of applied physiology at a university school of medicine . PATIENTS Thirty-five healthy , sedentary postmenopausal women , 55 to 70 years old . All women completed the study . There was 90 % compliance with exercise training . INTERVENTIONS All women were given calcium , 1500 mg daily . The exercise group did weight-bearing exercise ( walking , jogging , stair climbing ) at 70 % to 90 % of maximal oxygen uptake capacity for 50 to 60 min , 3 times weekly . MEASUREMENTS AND MAIN RESULTS Bone mineral content increased 5.2 % ( 95 % confidence interval [ CI ] , 2.0 % to 8.4 % ; P = 0.0037 ) above baseline after short-term training whereas there was no change ( -1.4 % ) in the control group . After 22 months of exercise , bone mineral content was 6.1 % ( 95 % CI , 3.9 % to 8.3 % above baseline ; P = 0.0001 ) in the long-term training group . After 13 months of decreased activity , bone mass was 1.1 % above baseline in the detraining group . CONCLUSIONS Weight-bearing exercise led to significant increases above baseline in bone mineral content which were maintained with continued training in older , postmenopausal women . With reduced weight-bearing exercise , bone mass reverted to baseline levels . Further studies are needed to determine the threshold exercise prescription that will produce significant increases in bone mass Abstract . There is evidence that high intensity resistance training promotes bone maintenance in older women , however , the effect of high intensity free weight training has not been investigated in older men or women . Furthermore , little is known about the chronic effect of weight training on serum insulin growth factor-I ( IGF-I ) in this population . We compared the effects of a moderate intensity seated resistance-training program with a high intensity st and ing free weight exercise program on bone mass and serum levels of IGF-I and IGFBP3 in healthy older men and women . Twenty-eight men ( 54.6 ± 3.2 years ) and 26 nonestrogen-replaced women ( 52.8 ± 3.3 years ) served as their own controls for 12 weeks , then were r and omly assigned to a moderate or high intensity training group and trained three times/week for 24 weeks . Prior to and after the control period and at the end of training , bone mass and body composition were assessed by dual energy X-ray absorptiometry ( DXA ) , muscle strength by isokinetic dynamometry , muscular power by Wingate Anaerobic Power Test , and IGF-I by radioimmunoassay ( RIA ) . A repeated measures analysis of covariance ( ANCOVA ) revealed that high intensity training result ed in a gain in spine BMD in men ( 1.9 % ) , P < 0.05 , but not in women , whereas moderate intensity training produced no changes in either gender at this site . Increases were observed at the greater trochanter , P < 0.03 , in men regardless of training intensity , but not in women at any hip site . However , when compared with zero , both men and women in the high intensity group demonstrated significant increases in trochanteric BMD ( 1.3 % and 2.0 % , respectively ) and a decrease in femoral BMD ( −1.8 % ) . Neither circulating serum IGF-I nor IGFBP3 were altered by either training regimen , but both training programs result ed in improvements in total body strength ( 37.62 % ) and lean mass ( males 4.1 % , females 3.1 % ) . We conclude that although resistance training of moderate to high intensity produced similar muscle changes in older adults , a higher magnitude is necessary to stimulate osteogenesis at the spine . However , at the spine , intensity was not sufficient to offset low levels of estrogen in early postmenopausal women . Furthermore , bone changes were not accompanied by changes in circulating serum levels of IGF-I or IGFBP3 The effects of weighted vest walking and strength-training exercises on bone mineral density ( BMD ) , balance , strength , and self-efficacy were tested in older women . Eighteen women , age 69.2 ± 3.5 years , were r and omly assigned to an exercise group ( EG ) ( n = 9 ) , or a sedentary control group ( CG ) ( n = 9 ) . The EG participated in 32 weeks ( three 1-h sessions/week ) of supervised strength training and walking , stair climbing , and balance exercises while wearing weighted vests . The CG did not exercise . All women  took Ca²+ and vitamin D during the study period . Measures included 1 ) BMD of the hip and lumbar spine measured by dual-energy X-ray absorptiometry , 2 ) strength , 3 ) balance , and 4 ) scores on a self-efficacy instrument . The EG had significant improvements in bone density of the femoral neck and balance and a significant weight loss ( P < 0.05 ) . There were no changes in self-efficacy in either group The purpose of this study was to determine the effects of 12 months of weight bearing and resistance exercise on bone mineral density ( BMD ) and bone remodeling ( bone formation and bone resorption ) in 2 groups of postmenopausal women either with or without hormone replacement therapy ( HRT ) .  Secondary aims were to characterize the changes in insulin-like growth factors-1 and -2 ( IGF-1 and -2 ) and IGF binding protein 3 ( IGFBP3 ) in response to exercise training .  Women who were 3–10 years postmenopausal ( aged 40–65 years ) were included in the study . Women in the HRT and no HRT groups were r and omized into the exercise intervention , result ing in four groups : ( 1 ) women not taking HRT , not exercising ; ( 2 ) those taking HRT , not exercising ; ( 3 ) those exercising , not taking HRT ; and ( 4 ) women exercising , taking HRT . The number of subjects per group after 1 year was 27 , 21 , 25 , and 17 , respectively . HRT  increased BMD at most sites whereas the combination of exercise and HRT produced increases in BMD greater than either treatment alone . Exercise training alone result ed in modest site-specific increases in BMD . Bone remodeling was suppressed in the groups taking HRT regardless of exercise status . The bone remodeling response to exercise training in women not taking HRT was not significantly different from those not exercising . However , the direction of change suggests an elevation in bone remodeling in response to exercise training , a phenomenon usually associated with bone loss . No training-induced differences in IGF-1 , IGF-2 , IGF-l : IGF-2 ( IGF-1 : IGF-2 ) , and IGFBP3 were detected This study compared the effects of two exercise training programs , 11 months in duration , on bone mineral density ( BMD ) in older , sedentary women . Thirty-nine women , aged 60 - 74 years , were assigned to the following groups : ( a ) a group that performed exercises that introduced stress to the skeleton through ground-reaction forces ( GRF ) ( i.e. , walking , jogging , stairs ) ; ( b ) a group that performed exercises that introduced stress to the skeleton through joint-reaction forces ( JRF ) ( i.e. , weight lifting , rowing ) ; or ( c ) a no-exercise control group .  BMD of the whole body , lumbar spine , proximal femur , and distal forearm was assessed five times at approximately 3-month intervals . The GRF and JRF exercise programs result ed in significant and similar increases in BMD of the whole body ( 2.0 + /- 0.8 % and 1.6 + /- 0.4 % , respectively ) , lumbar spine ( 1.8 + /- 0.7 % and 1.5 + /- 0.5 % , respectively ) , and Ward 's triangle region of the proximal femur ( 6.1 + /- 1.5 % and 5.1 + /- 2.1 % , respectively ) . There was a significant in BMD of the femoral neck only in response to the GRF exercise program ( GRF , 3.5 + /- 0.8 % ; JRF , -0.2 + /- 0.7 % ) . There were no significant changes in BMD in control subjects . Among all exercisers , there was a significant inverse ( r = -0.52 , p < 0.01 ) relationship between increases in whole body BMD and reductions in fat mass , suggesting a dose response effect of exercise on bone mass . Although femoral neck BMD was responsive only to the GRF exercise program , some adaptations ( i.e. , increase in lean body mass and strength ) that were specific to the JRF exercise program may be important in preventing osteoporotic fractures by reducing the risk for falls . It remains to be determined whether all of these benefits can be gained through a training program that combines the different types of exercises employed in this study PURPOSE The purpose of this study was to compare the effects of a high-load ( 80 % , 1-repetition maximum ( RM ) , 8 reps ) and a high-repetition ( 40 % , 1-RM , 16 reps ) resistance training protocol on muscular strength and bone mineral density ( BMD ) in early postmenopausal , estrogen-deficient women . The 6-month programs were matched initially for training volume ( 3 sets , 3 d x wk(-1 ) ) for 12 exercises selected to specifically load the spine and hip . METHODS Subjects included 25 women ( 41 - 60 yr ) who were matched by spine BMD then r and omly assigned to either the high-load ( HL , N = 10 ) , high-repetition ( HR , N = 7 ) , or control ( C , N = 8) groups . Dietary calcium intakes were supplemented to approximately 1500 mg x d(-1 ) . Total body , spine , and hip BMD ( DXA , Lunar Model DPX-IQ ) , upper and lower body muscular strength , and biochemical markers of bone turnover were measured at baseline and after 6 months of training . RESULTS There were no group differences in the baseline measures . Both training groups showed similar increases in biceps ( 20 % ) and rectus femoris ( 28 - 33 % ) cross-sectional areas , in lower body strength ( approximately 30 % ) and in hip strength ( 37 - 40 % ) . HL showed greater improvements in upper body strength ( HL 25 % , HR 16 % ) . Neither training group experienced significant increases in spine or hip BMD , although the HL total body BMD tended to decrease ( -1.1%+/-0.4 , P = 0.054 ) after training . Osteocalcin tended to increase ( P = 0.08 ) in all groups after training , and the % change in osteocalcin was positively related to % changes in the total hip ( r = 0.41 , P = 0.048 ) and the trochanter ( r = 0.42 , P = 0.04 ) BMD . CONCLUSION The high-load and high-repetition resistance training protocol s were both effective in improving muscular strength and size in postmenopausal women , indicating low-intensity resistance training can be beneficial for the muscular fitness in women for whom high-intensity exercise is contraindicated Osteoporosis is a bone disease associated with reduced bone mineral density result ing in debilitating bone fractures . According to the National Institutes 
    Output:
    
RESULTS The review revealed evidence to support the effectiveness of  weight training exercises  to increase BMD in postmenopausal women .
Weighted exercises can help in maintaining BMD in postmenopausal women and increasing BMD of the spine and hip in women with osteopenia and osteoporosis .