Twelve-month resistance and impact exercise program or risedronate provides a relative benefit to hip bone structure in postmenopausal women: results from a randomized controlled trial.

Bone strength estimates are important for fracture prevention. This study compared bone strength changes in postmenopausal women with low bone mass who were assigned to 12 months of exercise, a bone medication, or control. Exercise and bone medications benefited structure at the hip. Structure should be considered in fracture prevention research. PURPOSE: Exercise and bisphosphonates reduce fracture risk, but their impact on estimates of bone strength remains uncertain. This study compared changes in tibial bone strength using peripheral quantitative computed tomography (pQCT) and hip structure analysis (HSA) outcomes from dual-energy X-ray absorptiometry (DXA) scans in postmenopausal women with low bone mass assigned to 12 months of exercise, risedronate, or control. METHODS: In this RCT, 276 postmenopausal women within 6 years of menopause were randomly assigned to three groups: exercise (92), risedronate (91), or control (93). Exercise included weighted jogging and progressive resistance exercises; risedronate treatment was 150 mg monthly; all groups received calcium and vitamin D. pQCT and DXA images were obtained at baseline and 6 and 12 months and compared between groups over time. RESULTS: Participants had a mean (± SD) age of 54.5 (± 3.2) years with an average of 36.7 (± 40.7) months postmenopause. No significant differences were found between groups for the change in pQCT outcomes (volumetric bone mineral density, area, and strength estimates). At 12 months, mean percent differences (95% CI) in HSA measures between exercise and controls were as follows: intertrochanteric, cross-sectional area 2.25% (0.28, 4.12) (p = .03), cross-sectional moment of inertia (CSMI) 5.67% (1.47, 9.87) (p < .01), and section modulus (SM) 4.38% (1.02, 7.74) (p = .01), and narrow neck, average cortical thickness 2.37% (-0.08, 4.83) (p = .031). Mean percent differences (95% CI) in HSA measures between risedronate and control were as follows: intertrochanteric, CSMI 4.28% (-0.24, 8.81) (p = .03) and SM 3.35% (-0.21, 6.91) (p = .03), and shaft, subperiosteal width 0.82% (0.05, 1.58) (p = .047), CSMI 2.53% (0.88, 4.18) (p = .004), and SM 1.57% (0.34, 2.8) (p = .008). Exercise maintained neck-shaft angle compared to both control 1.27% (0.13, 2.41) (p = .04) and risedronate 1.31% (0.23, 2.39) (p = .03). All other differences for changes in HSA outcomes over time were not significantly different between the exercise and risedronate groups. CONCLUSION: Exercise and bisphosphonates may influence structural and strength estimates at the hip, but not at peripheral sites (tibia). Neither exercise nor bisphosphonates were found to be superior in improving estimates of hip bone strength.

Examining effects of habitual physical activity and body composition on bone structure in early post-menopausal women: a pQCT analysis.

After menopause, bones decline in structure and can break more easily. Physical activity can strengthen bones. This study investigated how activity and body composition can impact bone structure in post-menopausal women. Higher levels of physical activity were positively associated with bone structure at the lower leg. PURPOSE: The menopausal transition is characterized by dramatic bone loss, leading to an increased risk of fracture. Few studies have examined how modifiable risk factors influence bone structure. Thus, the objective of this cross-sectional study was to examine the relationship between habitual physical activity (PA), body composition, and bone structure in post-menopausal women with low bone mass. METHODS: Data was analyzed from 276 post-menopausal women with low bone mass enrolled in the Heartland Osteoporosis Prevention Study. Body composition and bone structure measures were collected using dual X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) at the tibia. Habitual PA was collected using the Human Activity Profile questionnaire. Multiple regression analysis was used to determine the relative impact of habitual PA and body composition on bone structure measures (density, area, and strength). Direct and/or indirect effects of PA on bone outcomes were assessed by path analysis. RESULTS: Mean (± SD) age of participants was 54.5 (± 3.2) years and average BMI was 25.7 (± 4.7). Mean T-score of the total lumber spine and hip were - 1.5 (± .6) and - 0.8 (± .59), respectively, with all women classified with low bone mass. Habitual PA had a significant positive effect on bone area and strength measures at the 66% site, and trend effects at the 4% site. Lean mass had a significant positive effect on area and strength at the 66% site and 4% site. Fat mass showed no effect at the 66% site, with a positive effect on density and strength at the 4% site. CONCLUSION: Increased habitual activity was related to improved bone structure of the tibia. Our results in post-menopausal women emphasize that PA and lean mass preservation are important for maintaining bone structure in the years following menopause.

Association of habits, triggers, glycaemic control, routines, stress and impulse control among emerging adults with type 1 diabetes.

AIM: Glycaemic control is known to be poor among emerging adults with type 1 diabetes, but the reasons for this are poorly understood. Examination of diabetes self-management-related habits, triggers and daily routines within the context of impulse control and perceived daily stress may provide increased understanding of glycaemic control during this transitional period. This study examined associations among checking blood glucose (CBG) habits, eating a meal (EAM) habits and glycaemic control within the context of CBG triggers, daily routines, impulse control and perceived daily stress, in emerging adults with type 1 diabetes. METHODS: A cross-sectional convenience sample of 100 emerging adults with type 1 diabetes was recruited from an outpatient diabetes care clinic for this age group. Participants self-reported frequency of CBG and EAM habits, CBG triggers, daily routines, perceived daily stress and impulse control. Glycaemic control values were obtained from medical records. Path analysis was performed. RESULTS: Better glycaemic control was positively and significantly associated with greater frequency of CBG and EAM habits. CBG habits were positively and significantly associated with CBG triggers and EAM habits. EAM habits were positively and significantly associated with daily routines. CONCLUSIONS: We suggest interventional research targeting CBG and EAM habits and daily routines to examine the impact on diabetes self-management and glycaemic control.

The effect of weight training on bone mineral density and bone turnover in postmenopausal breast cancer survivors with bone loss: a 24-month randomized controlled trial.

SUMMARY: This study examined whether 24 months of weight training exercises enhanced the effectiveness of risedronate, calcium, and vitamin D in maintaining or improving bone mineral density (BMD) in 223 postmenopausal breast cancer survivors. Subjects who were > or =50% adherent to exercise had no improvement in BMD but were less likely to lose BMD. INTRODUCTION: This study examined whether (1) postmenopausal breast cancer survivors (BCS) with bone loss taking 24 months of risedronate, calcium, and vitamin D had increased bone mineral density (BMD) at the total hip, femoral neck, L1-L4 spine, total radius and 33% radius, and decreased bone turnover; (2) subjects who also participated in strength/weight training (ST) exercises had greater increases in BMD and greater decreases in bone turnover; and (3) subjects who also exercised were more likely to preserve (at least maintain) BMD. METHODS: Postmenopausal BCS (223) were randomly assigned to exercise plus medication or medication only groups. Both groups received 24 months of 1,200 mg of calcium and 400 IU of vitamin D daily and 35 mg of risedronate weekly, and the exercise group additionally had ST exercises twice weekly. RESULTS: After 24 months, women who took medications without exercising had significant improvements in BMD at the total hip (+1.81%) and spine (+2.85%) and significant decreases in Alkphase B (-8.7%) and serum NTx (-16.7%). Women who also exercised had additional increases in BMD at the femoral neck (+0.29%), total hip (+0.34%), spine (+0.23%), total radius (+0.30%), and additional decreases in Alkphase B (-2.4%) and Serum NTx (-6.5%). Additional changes in BMD and bone turnover with exercise were not significant. Subjects who were > or =50% adherent to exercise were less likely to lose BMD at the total hip (chi-square [1] = 4.66, p = 0.03) and femoral neck (chi-square [1] = 4.63, p = 0.03). CONCLUSION: Strength/weight training exercises may prevent loss of BMD in postmenopausal BCS at risk for bone loss.