Osteoporosis is a major public health concern. The combination of exercise, hormone replacement therapy, and calcium supplementation may have added benefits for improving bone mineral density compared to a single intervention. To test this notion, 320 healthy, non-smoking postmenopausal women, who did or did not use hormone replacement therapy (HRT), were randomized within groups to exercise or no exercise and followed for 12 months. All women received 800 mg calcium citrate supplements daily. Women who exercised performed supervised aerobic, weight-bearing and weight-lifting exercise, three times per week in community-based exercise facilities. Regional bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry. Women who used HRT, calcium, and exercised increased femoral neck, trochanteric and lumbar spine bone mineral density by approximately 1-2%. Trochanteric BMD was also significantly increased by approximately 1.0% in women who exercised and used calcium without HRT compared to a negligible change in women who used HRT and did not exercise. The results demonstrate that regional BMD can be improved with aerobic, weight-bearing activity combined with weight lifting at clinically relevant sites in postmenopausal women. The response was significant at more sites in women who used HRT, suggesting a greater benefit with hormone replacement and exercise compared to HRT alone.

2 ; 3 to 10 years postmenopausal) participated in the study. Height, weight, BMI, and %Fat, as assessed by DXA, were measured. Receiver operating characteristic analysis was performed to evaluate the ability of BMI to discriminate obesity from non-obesity using 38%Fat as the criterion value. Results: A moderately high relationship was observed between BMI and %Fat (r ϭ 0.81; y ϭ 1.41x ϩ 2.65) with a SE of estimate of 3.9%. Eighty-one percent of other studies examined fell within 1 SE of estimate as derived from our study. Receiver operating characteristic analysis showed that BMI is a good diagnostic test for obesity. The cutoff for BMI corresponding to the criterion value of 38%Fat that maximized the sum of the sensitivity and specificity was 24.9 kg/m 2 . The truepositive (sensitivity) and false-positive (1 Ϫ specificity) rates were 84.4% and 14.6%, respectively. The area under the curve estimate for BMI was 0.914. Discussion: There is a strong association between %Fat and BMI in postmenopausal women. Current NIH BMI-based classifications for obesity may be misleading based on currently proposed %Fat standards. BMI Ͼ25 kg/m 2 rather than BMI Ͼ30 kg/m 2 may be superior for diagnosing obesity in postmenopausal women.

Despite the widespread use of and acceptance of muscular fitness field tests in national youth fitness test batteries, little is known about how these field tests compare to 1 repetition maximum (1RM) strength in children. Therefore, the aim of this study was to characterize and identify correlates of muscular strength in children 7 to 12 years of age. Ninety children (39 girls and 51 boys) between the ages of 6.7 and 12.3 years volunteered to participate in this study. Children were tested on 1RM chest press (CP) strength, 1RM leg press (LP) strength, handgrip strength, vertical jump, long jump, sit and reach flexibility, and height and weight (used to determine body mass index [BMI]). For the combined sample, LP 1RM ranged from 75% to 363% of body weight and CP 1RM ranged from 25% to 103% of body weight. Multiple regression analyses predicting LP 1RM showed that BMI and long jump were significant (R = 44.4% with age and gender not significant) and BMI and vertical jump were significant (R = 40.8% with age and gender not significant). Multiple regression analyses predicting CP 1RM showed that BMI and handgrip strength were significant (R = 58.6% with age and gender not significant). Age and gender alone accounted for 4.6% (not significant) of the variation in LP 1RM and 15.4% (significant) in CP 1RM. In summary, these data indicate that BMI, handgrip strength, long jump, and vertical jump relate to 1RM strength in children and therefore may be useful for assessing muscular fitness in youths.

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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 randomized into the exercise intervention, resulting 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 resulted 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.