Effect of exercise training and detraining on bone mineral density in postmenopausal women with osteoporosis

Effects of exercise based on ACSM recommendations on bone mineral density in individuals with osteoporosis: a systematic review and meta-analyses of randomized controlled trials

Purpose: To analyze the effects of different exercise dose on lumbar spine and femoral neck bone mineral density (BMD) in individuals with osteoporosis (OP). Design: A systematic search was conducted in four electronic databases, namely, PubMed, Embase, Web of Science, and Cochrane, with the topic of the impact of exercise on BMD in individuals with OP. Randomized controlled trials comparing exercise intervention with no intervention were identified, and changes in lumbar spine and femoral neck BMD were reported and evaluated using standardized mean difference (SMD) and 95% confidence interval (95% CI). The intervention measures in the studies were evaluated and categorized as high adherence with the exercise testing and prescription recommendations for individuals with OP developed by the American College of Sports Medicine (ACSM) or low/uncertainty adherence with ACSM recommendations. A random effects model was used to conduct meta-analyses and compare the results between subgroups. Results: A total of 32 studies involving 2005 participants were included in the analyses, with 14 studies categorized as high adherence with ACSM recommendations and 18 studies categorized as low or uncertain adherence. In the analyses of lumbar spine BMD, 27 studies with 1,539 participants were included. The combined SMD for the high adherence group was 0.31, while the combined SMD for the low or uncertain adherence group was 0.04. In the analyses of femoral neck BMD, 23 studies with 1,606 participants were included. The combined SMD for the high adherence group was 0.45, while the combined SMD for the low or uncertain adherence group was 0.28. Within resistance exercise, the subgroup with high ACSM adherence had a greater impact on lumbar spine BMD compared to the subgroup with low or uncertain ACSM adherence (SMD: 0.08 > -0.04). Similarly, for femoral neck BMD, resistance exercise with high ACSM adherence had a higher SMD compared to exercise with low or uncertain ACSM adherence (SMD: 0.49 > 0.13). Conclusion: The results suggest that exercise interventions with high adherence to ACSM recommendations are more effective in improving lumbar spine and femoral neck BMD in individuals with OP compared to interventions with low or uncertain adherence to ACSM recommendations. Systematic Review Registration: PROSPERO, identifier CRD42023427009.

Exercise training and bone mineral density in postmenopausal women: an updated systematic review and meta-analysis of intervention studies with emphasis on potential moderators

The aim of this systematic review and meta-analysis was (1) to determine exercise effects on bone mineral density (BMD) in postmenopausal women and (2) to address the corresponding implication of bone and menopausal status or supervision in postmenopausal women. A comprehensive search of eight electronic databases according to the PRISMA statement up to August 9, 2022, included controlled exercise trials ≥ 6 months. BMD changes (standardized mean differences: SMD) at the lumbar spine (LS), femoral neck (FN), and total hip (TH) were considered as outcomes. Study group comparisons were conducted for osteopenia/osteoporosis versus normal BMD, early versus late postmenopausal women, and predominantly supervised versus predominantly non-supervised study arms. We applied an inverse heterogeneity (IVhet) model. In summary, 80 studies involving 94 training and 80 control groups with a pooled number of 5581 participants were eligible. The IVhet model determined SMDs of 0.29 (95% CI: 0.16-0.42), 0.27 (95% CI: 0.16-0.39), and 0.41 (95% CI: 0.30-0.52) for LS, FN, and THBMD, respectively. Heterogeneity between the trial results varied from low (I2 = 20%, TH BMD) to substantial (I2 = 68%, LS-BMD). Evidence for publication bias/small study effects was negligibly low (FN-, TH-BMD) to high (LSBMD). We observed no significant differences (p > .09) for exercise effects on LS-, FN-, or TH-BMD-LS between studies/study arms with or without osteopenia/osteoporosis, early versus late postmenopausal women, or predominantly supervised versus non-supervised exercise programs. Using robust statistical methods, the present work provides further evidence for a positive effect of exercise on BMD in postmenopausal women. Differences in bone status (osteopenia/osteoporosis versus normal bone), menopausal status (early versus late postmenopausal), and supervision (yes versus no) did not significantly affect the exercise effects on BMD at LS or proximal femur.

Impact of 3 months of detraining after high intensity exercise on menopause-related symptoms in early postmenopausal women - results of the randomized controlled actlife project

Regular exercise might reduce postmenopausal symptoms, however even short-moderate periods of absence from exercise training might significantly reduce these positive effects. The aim of the study was thus to determine detraining effects on postmenopausal symptoms after a 3-month detraining period in early post-menopausal women. After 13 months, the exercise group (EG: n = 27; 54.6 ± 2.0; 23.6 ± 3.3 kg/m²) had to abruptly stop their supervised, facility-based, high intensity aerobic and resistance group exercise conducted three times per week due to the COVID-19 pandemic and the corresponding lockdown of all training facilities in Germany. In parallel, the control group (CG: n = 27; 55.6 ± 1.6 years, 25.2 ± 5.2 kg/m²) had to terminate their low-intensity exercise program performed once per week. Study endpoint as determined after 3 months of detraining was menopausal symptoms as determined by the Menopausal Rating Scale II (MRS II). The intention to treat principle with multiple imputation was applied. After 13 months of intense multicomponent exercise and significant exercise-induced effects on menopausal symptoms, a further 3 months of detraining resulted in non-significant deteriorations (p = .106) in the exercise group, while non-significant improvements were observed in the control group (p = .180). Corresponding group differences were significant (p = .036) after detraining. Of importance, self-reported individual outdoor activities increased by about 40% in both groups during the three-month lock-down period. Three months of absence from a supervised high-intensity group exercise protocol resulted in detraining effects on postmenopausal symptoms even when outdoor physical activity was increased significantly.

Trial registration number

ClinicalTrials.gov: NCT03959995.

Regulation of bone health through physical exercise: Mechanisms and types

Osteoporosis, characterized by bone mineral density reduction, bone mass loss, increased bone fragility, and propensity to fractures, is a common disease in older individuals and one of the most serious health problems worldwide. The imbalance between osteoblasts and osteoclasts results in the predominance of bone resorption and decreased bone formation. In recent years, it has been found that regular and proper exercise not only helps prevent the occurrence of osteoporosis but also adds benefits to osteoporosis therapy; accordingly, bone homeostasis is closely associated with mechanical stress and the intricate crosstalk between osteoblasts and osteoclasts. In this review, we summarize the mechanisms of exercise on osteoporosis and provide new proposals for the prevention and treatment of osteoporosis.

Effects of physical exercise on bone mineral density in older postmenopausal women: a systematic review and meta-analysis of randomized controlled trials

Osteoporosis or decreased bone mineral density (BMD) is the most important risk factor for fractures, especially in older postmenopausal women (PMW). However, the interactions between exercise training and bone mineral density are not completely understood. We evaluated the effects of physical exercise on BMD in women aged ≥ 60 years postmenopausal.

PURPOSE

This systematic review and meta-analysis sets out to determine the effects of physical exercise on BMD in older postmenopausal women.

METHODS

A systematic search was conducted in Medline, Science Direct, Cochrane, PubMed, CINAHL, Google Scholar, Scopus, and ProQuest up to December 25, 2021. Fifty-three studies, which assessed a total of 2896 participants (mean age: between 60 and 82 years), were included and analyzed using a random-effects model to estimate weighted mean differences (WMD) with 95% confidence intervals (CI).

RESULTS

The meta-analysis found that exercise training significantly (p < 0.05) increased femoral neck (WMD: 0.01 g/cm²; 95% CI, 0.00 to 0.01], p = 0.0005; I² = 57%; p < 0.0001), lumbar spine (WMD: 0.01 g/cm², 95% CI, 0.01 to 0.02], I² = 81%; p = 0.0001), and trochanter (WMD: 0.01 g/cm², 95% CI 0.00, 0.02]; p = 0.009; I² = 17%; p = 0.23). There were no significant differences between the intervention and control groups for total body and total hip BMD.

CONCLUSION

Our findings suggest that exercise training may improve bone mineral density in older PMW. This improvement is mediated by increases in the femoral neck, lumbar spine, and trochanter BMD. Further long-term studies are required to confirm these findings.

Effects of non-supervised exercise interventions on bone mineral density in adult women: a systematic review and meta‑analysis

Osteoporosis is a major health issue worldwide. This study analyzes the effects of non-supervised osteoporosis prevention programs on bone mineral density. Non-supervised exercise increases femoral neck and lumbar spine bone mineral density in adult women. Thus, it might be effective for preventing or treating osteoporosis or osteopenia in this population.

INTRODUCTION

Osteoporosis is a major health issue worldwide. Social distancing measures due to COVID-19 have hindered the chances to take part in supervised osteoporosis prevention exercise programs. The purpose of the present study is to systematically review and meta-analyze the effects of non-supervised osteoporosis prevention exercise programs on bone mineral density (BMD) in adult women.

METHODS

A comprehensive search of electronic databases (n = 7) was conducted including (a) prospective randomized controlled trials (RCTs) comparing at least one exercise group vs. a control group with sedentary lifestyle or sham exercises; (b) baseline and follow-up BMD values, or BMD changes from baseline, at any skeletal site; (c) women over 30 years old; and (d) non-supervised exercise programs only. Subgroup analyses were performed for menopausal status, intervention duration, type of exercise, and osteopenia/osteoporosis status.

RESULTS

Ten studies were included (n = 668). Random effect analyses showed that unsupervised exercise had beneficial effects on lumbar spine (LS) BMD with standardized mean difference (SMD) = 0.40 (95% confidence interval (CI): 0.03-0.77), and femoral neck (FN) BMD with SMD = 0.51 (95% CI: 0.16-0.85). Unsupervised exercise increased LS (SMD = 0.73 (95% CI: 0.13-1.33)) and FN BMD (SMD = 0.85 (95% CI: 0.33-1.37)) in women with osteopenia/osteoporosis, but not in healthy counterparts.

CONCLUSION

Non-supervised exercise improves FN and LS BMD in adult women. Beneficial effects of exercise on FN and LS BMD might be more pronounced in those with poor bone health compared with healthy counterparts. More RCTs prescribing non-supervised, osteogenic exercise are required in this population. It is necessary to investigate the efficacy of remote/assistive technologies for delivering and monitoring non-supervised exercise interventions.

Regular Exercise Decreases the Risk of Osteoporosis in Postmenopausal Women

Regular exercise can regulate bone maintenance and improve bone health. However, large-scale epidemiological studies on the association between regular exercise and incident osteoporosis in menopausal women are still lacking. We aimed to examine the relationship between exercise and the risk of osteoporosis in menopausal women. In cross-sectional analysis, we enrolled 30,046 postmenopausal women with available information from the database of the Taiwan Biobank (TWB). We divided them into two groups according to their status of regular exercise, i.e., no exercise and regular exercise groups. A t-score of -2.5 or more standard deviations (SDs) below that of a young adult was defined as osteoporosis. Logistic regression after adjusting for confounding factors was used to analyze the association between regular exercise and the prevalence of osteoporosis. Furthermore, the risk of incident osteoporosis development was analyzed in a longitudinal cohort of 6,785 postmenopausal women without osteoporosis at baseline using a Kaplan-Meier analysis and a log-rank test. The mean age of subjects in the cross-sectional cohort was 59 years old. Fifty-six percent of them were exercising regularly. Osteoporosis was observed in 1,886 (14.2%) and 2,254 (13.4%) participants in the no exercise and regular exercise groups. Lower risk of osteoporosis was noted in postmenopausal women with regular exercise when compared with those without regular exercise [odds ratio (OR), 0.76; 95% confidence interval (95% CI), 0.71-0.81]. In the longitudinal cohort, incident osteoporosis was found in 430 (10.5%) women with regular exercise and 299 (11.2%) women without exercise during a mean follow-up of 45 months. Cox regression analysis revealed that the risk for incident osteoporosis was lower in postmenopausal women with regular exercise than those without exercise [hazard ratio (HR), 0.83; 95% CI, 0.71-0.97]. Our study suggests that regular exercise is associated with a reduced risk of osteoporosis in postmenopausal women and strengthens the importance of exercise for the prevention of osteoporosis.

Satisfaction with the walking-related environment during COVID-19 in South Korea

This study aimed to examine the satisfaction level differences between urban and rural areas with regard to their walking environment during the COVID-19 pandemic in South Korea. This online cross-sectional research was conducted using a mobile health application. Overall, 1,032 local residents who participated in the mobile healthcare program of a public health center were classified as being from either urban (n = 481, 46.6%) or rural areas (n = 551, 53.4%) for the purpose of this study. The Walkability Checklist, which includes sociodemographic information, was employed using a Chi-square test and a multivariate logistic regression to investigate whether or not the participants were satisfied with the environmental factors associated with walking. It was found that both urban and rural areas were more likely to be unsatisfied with walking comfort (adjusted OR: 24.472, 95% CI: 14.937-40.096). Regarding the walking comfort aspects of the walking environment, urban residents chose poor landscape ("needed more grass, flowers, or trees"; aOR: 13.561, 95% CI: 3.619-50.823) as their primary dissatisfaction, and rural residents chose messy streets ("dirty, lots of litter or trash"; aOR: 29.045, 95% CI: 6.202-136.015). Compared with urban residents, rural residents were more discontented with the walking environment. Thus, to promote walking activities at the community level, it is necessary to focus on walking comfort, and implement efforts related to environmental beautification.

The Potential Mechanism of Exercise Combined with Natural Extracts to Prevent and Treat Postmenopausal Osteoporosis

Postmenopausal osteoporosis (PMOP) is a systemic chronic bone metabolic disease caused by the imbalance between bone formation and bone resorption mediated by estrogen deficiency. Both exercise and natural extracts are safe and effective means to prevent and control PMOP. The additive effect of exercise synergy extract against PMOP may be no less than that of traditional medicine. However, the mechanism of action of this method has not been clarified in detail. A large number of studies have shown that the pathogenesis of PMOP mainly involves the OPG-RANKL-RANK system, inflammation, and oxidative stress. Based on the abovementioned approaches, the present study reviews the anti-PMOP effects and mechanisms of exercise and natural extracts. Finally, it aims to explore the possibility of the target of the two combined anti-PMOP through this approach, thereby providing a new perspective for joint intervention research and providing a new direction for the treatment strategy of PMOP.

Detraining Effects on Musculoskeletal Parameters in Early Postmenopausal Osteopenic Women: 3-Month Follow-Up of the Randomized Controlled ACTLIFE Study

Periods of absence from supervised group exercise while maintaining physical activity might be a frequent pattern in adults' exercise habits. The aim of the present study was to determine detraining effects on musculoskeletal outcomes after a 3-month detraining period in early post-menopausal, osteopenic women. Due to the COVID-19 pandemic, we terminated the 18-month randomized controlled ACTLIFE exercise intervention immediately after the 13-month follow-up assessment. This put an abrupt stop to the high-intensity aerobic and resistance group exercise sessions undertaken three times per week by the exercise group (EG: n = 27) and the gentle exercise program performed once per week for the attention control group (CG: n = 27); but both groups were permitted to conduct individual outdoor activity for the 3-month lock-down period. Study endpoints were lean body mass (LBM), bone mineral density (BMD) at the lumbar spine (LS), maximum hip-/leg extension strength and power. Detraining-induced reductions of LBM, hip/leg strength and power (but not BMD-LS) were significantly greater (p < 0.001 to p = 0.044) compared with the CG. Significant exercise effects, i.e. differences between EG and CG, present after 13 months of exercise, were lost after 3 months of detraining for LBM (p = 0.157) and BMD-LS (p = 0.065), but not for strength (p < 0.001) and power (p < 0.001). Of note, self-reported individual outdoor activities and exercise increased by about 40% in both groups during the lock-down period. Three months' absence from a supervised group exercise protocol resulted in considerable detraining effects for musculoskeletal parameters. Thus, exercise programs for adults should be continuous rather than intermittent.Trial registration number: ClinicalTrials.gov: NCT04420806, 06.05.2020.

The Effect of Impact Exercise (Alone or Multicomponent Intervention) on Health-Related Outcomes in Individuals at Risk of Fractures: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Exercise is commonly recommended to prevent and manage osteoporosis. High magnitude strains at rapid rate and short bouts should theoretically elicit an osteogenic response; however, the effects of different levels of impact exercises on several outcomes in people at risk of fracture are still unknown.

OBJECTIVE

To report the effect of impact exercise on falls, fractures, adverse events, mortality, bone mineral density (BMD), physical functioning, and health-related quality of life (QoL).

METHODS

We included randomized controlled trials testing the effect of impact exercise compared with a non-exercise control on outcomes in adults ≥ 50 years with low BMD or fragility fractures. Two reviewers selected studies and extracted data. Where possible, we pooled outcomes using mean difference (MD) with a fixed-effects model and 95% confidence interval (CI). We reported risk of bias using Cochrane and certainty of evidence using GRADE.

RESULTS

We included 29 trials; 19 studies evaluated impact exercise alone, and the remaining trials combined impact with resistance or balance training. Impact exercise alone or combined with resistance training improved Timed Up-and-Go values (MD - 0.95 s, 95% CI - 1.09 to - 0.81, low certainty evidence) and lumbar spine (MD 0.04 g/cm², 95% CI 0.02-0.06, low certainty evidence) and femoral neck BMD (MD 0.04 g/cm², 95% CI 0.02-0.07, low certainty evidence). Impact exercise did not improve health-related QoL assessed with QUALEFFO-41 (MD 0.06, 95% CI - 2.18 to 2.30, moderate certainty evidence). The effects of impact exercise on falls, fractures, and mortality are uncertain due to insufficient data. Many trials had a high risk of bias for two or more items.

CONCLUSIONS

There is low certainty evidence that impact exercise may improve physical function and BMD in people at risk of fracture. The effect of impact exercises on falls, fractures, and mortality remains unclear. Our findings should be interpreted with caution due to risk of bias and small sample sizes.

TRIAL REGISTRATION

Registered in Prospero (CRD42018115579) on January 30, 2019.

The Effects of Walking or Nordic Walking in Adults 50 Years and Older at Elevated Risk of Fractures: A Systematic Review and Meta-Analysis

Walking is a common activity among older adults. However, the effects of walking on health-related outcomes in people with low bone mineral density (BMD) are unknown. The authors included randomized controlled trials comparing walking to control in individuals aged ≥50 years with low BMD and at risk of fractures. The authors identified 13 randomized controlled trials: nine multicomponent interventions including walking, one that was walking only, and three Nordic walking trials. Most studies had a high risk of bias. Nordic walking may improve the Timed Up-and-Go values (1.39 s, 95% CI [1.00, 1.78], very low certainty). Multicomponent interventions including walking improved the 6-min walk test (39.37 m, 95% CI [21.83, 56.91], very low certainty) and lumbar spine BMD (0.01 g/cm2, 95% CI [0.00, 0.03], low certainty evidence). The effects on quality of life or femoral neck BMD were not significant. There were insufficient data on fractures, falls, or mortality. Nordic walking may improve physical functioning. The effects on other outcomes are less certain; one may need to combine walking with other exercises to be of benefit.

Progressive Resistance Training for Improving Health-Related Outcomes in People at Risk of Fracture: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Osteoporosis clinical practice guidelines recommend exercise to prevent fractures, but the efficacy of exercise depends on the exercise types, population studied, or outcomes of interest. The purpose of this systematic review was to assess the effects of progressive resistance training (PRT) on health-related outcomes in people at risk of fracture.

METHODS

Multiple databases were searched in October 2019. Eligible articles were randomized controlled trials of PRT interventions in men and women ≥50 years with low bone mineral density (BMD) or fracture history. Descriptive information and mean difference (MD) and SD were directly extracted for included trials. A total of 53 studies were included.

RESULTS

The effects of PRT on the total number of falls (incidence rate ratio [IRR] = 1.05; 95% CI = 0.91 - 1.21; 7 studies) and on the risk of falling (risk ratio [RR] = 1.23; 95% CI = 1.00 - 1.51; 5 studies) are uncertain. PRT improved performance on the Timed "Up and Go" test (MD = -0.89 seconds; 95% CI = -1.01 to -0.78; 13 studies) and health-related quality of life (standardized MD = 0.32; 95% CI = 0.22-0.42; 20 studies). PRT may increase femoral neck (MD = 0.02 g/cm2; 95% CI = 0.01-0.03; 521 participants, 5 studies) but not lumbar spine BMD (MD = 0.02 g/cm2; 95% CI = -0.01-0.05; 4 studies), whereas the effects on total hip BMD are uncertain (MD = 0.00 g/cm2; 95% CI = 0.00-0.01; 435 participants, 4 studies). PRT reduced pain (standardized MD = -0.26; 95% CI = -0.37 to -0.16; 17 studies). Sensitivity analyses, including PRT-only studies, confirmed these findings.

CONCLUSION

Individuals at risk of fractures should be encouraged to perform PRT, as it may improve femoral neck BMD, health-related quality of life, and physical functioning. PRT also reduced pain; however, whether PRT increases or decreases the risk of falls, the number of people experiencing a fall, or the risk of fall-related injuries is uncertain.

IMPACT

Individuals at risk of fractures should be encouraged to perform PRT, as it may have positive effects on femoral neck BMD, health-related quality of life, physical functioning, and pain, and adverse events are rare.

LAY SUMMARY

Exercise is recommended for people at risk of osteoporotic fractures. Our study showed that progressive resistance training improves physical functioning, quality of life, and reduces pain. The effects of progressive resistance training on the risk of falling are unclear. Adverse events are rare, and often minor (eg, soreness, pain, musculoskeletal injury). Considering the benefits and safety, people at risk of fractures should engage in progressive resistance training interventions.

Detraining effects after 18 months of high intensity resistance training on osteosarcopenia in older men-Six-month follow-up of the randomized controlled Franconian Osteopenia and Sarcopenia Trial (FrOST)

PURPOSE

Detraining after dedicated exercise programs might be a frequent situation in older people's exercise patterns. The aim of the present study was thus to determine the effects of 6 months of detraining after 18 months of high intensity resistance exercise (HIT-RT) on musculoskeletal outcomes in older men with sarcopenia.

METHODS

Community-dwelling men aged 72 years and older with osteosarcopenia (n = 43) were randomly assigned to an 18-month HIT-RT (EG: n = 21) or a non-training control group (CG, n = 22). After the intervention, participants of the EG stopped HIT-RT for 6 months, but continued their habitual physical activity. Study outcomes were skeletal muscle mass index, bone mineral density (BMD) at the lumbar-spine and total-hip, maximum hip/leg-extensor strength, handgrip strength and gait velocity. We applied an intention-to-treat analysis with multiple imputation.

RESULTS

Changes in the HIT-RT were much more pronounced during the detraining period compared with the CG, although this effect was only significant for skeletal muscle mass index and hip-/leg-extensor strength (p = .002 and p = .013), but not for lumbar-spine BMD (p = .068), total-hip BMD (p = .069), handgrip strength (p = .066) or gait velocity (p = .067). Apart from total-hip BMD (p = .055), handgrip strength (p = .069) and gait velocity (p = .881) values of the HIT-RT group decreased significantly during detraining. However, after 24 months, overall effects (p < .001) were still observed for skeletal muscle mass index and hip-/leg-extensor strength.

CONCLUSION

Although unable to state from which point in time relevant detraining effects emerge, we conclude that health care providers should focus on continuous rather than intermitted exercise programs for older people. Clinical trial number: clinicalTrials.gov: NCT03453463; NCT04444661.

Effects of Different Types of Exercise on Bone Mineral Density in Postmenopausal Women: A Systematic Review and Meta-analysis

In this sub-analysis of a comprehensive meta-analysis, we aimed to determine the effect of different types of exercise on (areal) bone mineral density (BMD) in postmenopausal women. A systematic review of the literature according to the PRISMA statement included (a) controlled trials, (b) with at least one exercise and one control group, (c) intervention ≥ 6 months, (d) BMD assessments at lumbar spine (LS), femoral neck (FN) or total hip (TH), (e) in postmenopausal women. Eight electronic databases were scanned without language restrictions up to March 2019. The present subgroup analysis was conducted as a mixed-effect meta-analysis with "type of exercise" as the moderator. The 84 eligible exercise groups were classified into (a) weight bearing (WB, n = 30) exercise, (b) (dynamic) resistance exercise (DRT, n = 18), (c) mixed WB&DRT interventions (n = 36). Outcome measures were standardized mean differences (SMD) for BMD-changes at LS, FN and TH. All types of exercise significantly affect BMD at LS, FN and TH. SMD for LS average 0.40 (95% CI 0.15-0.65) for DRT, SMD 0.26 (0.03-0.49) for WB and SMD 0.42 (0.23-0.61) for WB&DRT. SMD for FN were 0.27 (0.09-0.45) for DRT, 0.37 (0.12-0.62) for WB and 0.35 (0.19-0.51) for WB&DRT. Lastly, SMD for TH changes were 0.51 (0.28-0.74) for DRT, 0.40 (0.21-0.58) for WB and 0.34 (0.14-0.53) for WB&DRT. In summary, we provided further evidence for the favorable effect of exercise on BMD largely independent of the type of exercise. However, in order to generate dedicated exercise recommendations or exercise guideline, meta-analyses might be a too rough tool.

Rehabilitation of Patients With Osteoporotic Fractures

Osteoporosis is a silent, asymptomatic disease until a fragility fracture is sustained. Fractures greatly affect the physical functioning and health-related quality of life and are associated with increased mortality and morbidity rates. Furthermore, once a fragility fracture occurs, the patient is more susceptible to sustain further fractures. Repeated falls are the main causes of fractures in patients with osteoporosis. The management of osteoporosis postfracture is a combination of medical treatment, nutritional interventions, and rehabilitation in order to improve activities of daily living to prevent falls and increase safety while reducing the loss of bone mass. In this article the principles of fracture prevention and physical rehabilitation of patients with osteoporosis postvertebral and hip fragility fractures will be discussed, as well as the rehabilitation management to prevent further falls and fractures.

The Effect of Kinesitherapy on Bone Mineral Density in Primary Osteoporosis: A Systematic Review and Meta-Analysis of Randomized Controlled Trial

Objective

Osteoporosis (OP) is a well-established age-related disease, pathologically characterized by bone microarchitectural deterioration, increased fragility, and low BMD. Primary osteoporosis (POP) is the most common type of OP.

Methods

Publications pertaining to the effectiveness of kinesitherapy on BMD in POP from PubMed, SCI, Cochrane Library, Embase, VIP, CNKI, and Wanfang Database were retrieved from their inception to October 2019.

Results

A total of 21 studies with 1840 participants were included. The results of the meta-analysis revealed that kinesitherapy plus antiosteoporosis medications had a positive effect on lumbar spine BMD when the duration of intervention was 6 months (MD = 0.11 g/cm²; 95% CI: 0.06–0.15; P < 0.0001) or >6 months (MD = 0.04 g/cm²; 95% CI: 0.02–0.06; P < 0.0001) compared with antiosteoporosis medications alone. Additional kinesitherapy plus antiosteoporosis medications were associated with improved femoral neck BMD compared with antiosteoporosis medications alone (MD = 0.09 g/cm²; 95% CI: 0.03–0.16; P=0.004).

Conclusions

Kinesitherapy plus antiosteoporosis medications significantly improved lumbar spine and femoral neck BMD in the current low-quality evidence. Additional high-quality evidence is required to confirm the effect of kinesitherapy on BMD in patients with POP.

Effect of Exercise Training on Bone Mineral Density in Post-menopausal Women: A Systematic Review and Meta-Analysis of Intervention Studies

Osteoporosis is a major health problem in post-menopausal women (PMW). Exercise training is considered a cost-effective strategy to prevent osteoporosis in middle aged-older people. The purpose of this study is to summarize the effect of exercise on BMD among PMW. A comprehensive search of electronic databases was conducted through PubMed, Scopus, Web of Science, Cochrane, Science Direct, Eric, ProQuest, and Primo. BMD changes (standardized mean differences: SMD) of the lumbar spine (LS) femoral neck (FN) and/or total hip were considered as outcome measures. After subgroup categorization, statistical methods were used to combine data and compare subgroups. Seventy-five studies were included. The pooled number of participants was 5,300 (intervention group: n = 2,901, control group: n = 2,399). The pooled estimate of random effect analysis was SMD = 0.37, 95%-CI: 0.25–0.50, SMD = 0.33, 95%-CI: 0.23–0.43, and SMD = 0.40, 95%-CI: 0.28–0.51 for LS, FN, and total Hip-BMD, respectively. In the present meta-analysis, there was a significant (p < 0.001), but rather low effect (SMD = 0.33–0.40) of exercise on BMD at LS and proximal femur. A large variation among the single study findings was observed, with highly effective studies but also studies that trigger significant negative results. These findings can be largely attributed to differences among the exercise protocols of the studies. Findings suggest that the true effect of exercise on BMD is diluted by a considerable amount of studies with inadequate exercise protocols.

Impact of calcium, vitamin D, vitamin K, oestrogen, isoflavone and exercise on bone mineral density for osteoporosis prevention in postmenopausal women: a network meta-analysis

The aim of this network meta-analysis is to compare bone mineral density (BMD) changes among different osteoporosis prevention interventions in postmenopausal women. We searched MEDLINE, Embase and Cochrane Library from inception to 24 February 2019. Included studies were randomised controlled trials (RCT) comparing the effects of different treatments on BMD in postmenopausal women. Studies were independently screened by six authors in three pairs. Data were extracted independently by two authors and synthesised using Bayesian random-effects network meta-analysis. The results were summarised as mean difference in BMD and surface under the cumulative ranking (SUCRA) of different interventions. A total of ninety RCT (10 777 participants) were included. Ca, vitamin D, vitamin K, oestrogen, exercise, Ca + vitamin D, vitamin D + vitamin K and vitamin D + oestrogen were associated with significantly beneficial effects relative to no treatment or placebo for lumbar spine (LS). For femoral neck (FN), Ca, exercise and vitamin D + oestrogen were associated with significantly beneficial intervention effects relative to no treatment. Ranking probabilities indicated that oestrogen + vitamin D is the best strategy in LS, with a SUCRA of 97·29 % (mean difference: +0·072 g/cm2 compared with no treatment, 95 % credible interval (CrI) 0·045, 0·100 g/cm2), and Ca + exercise is the best strategy in FN, with a SUCRA of 79·71 % (mean difference: +0·029 g/cm2 compared with placebo, 95 % CrI –0·00093, 0·060 g/cm2). In conclusion, in postmenopausal women, many interventions are valuable for improving BMD in LS and FN. Different intervention combinations can affect BMD at different sites diversely.

Facilitators and barriers to exercise adherence in patients with osteopenia and osteoporosis: a systematic review

The aim of this study was to categorize the facilitators and barriers of exercise and identify methods to promote exercise adherence in the osteoporosis population. Despite the fair methodological quality of included randomized controlled trials (RCTs), less than 75 % identified facilitators and barriers to exercise. Methods to promote and measure exercise adherence were poorly reported.

INTRODUCTION

Several studies have shown exercise to be successful in maintaining or increasing BMD in individuals with low bone mass. Yet, adherence to exercise is poor, with 50 % of those registered in an exercise program dropping out within the first 6 months, lack of time being the number one barrier in many populations. However, in the osteoporosis population, the main facilitator and barrier to exercise is still unclear. The aim of this study is to examine the extent to which RCTs reported the facilitators and the barriers to exercise and identified methods to promote adherence to an exercise program.

METHODS

PubMed, CINHAL, EMBASE, and the Cochrane Review were queried using a predefined search criterion, and the resulting citations were imported into DistillerSR. Screening was carried out by two independent reviewers, and articles were included in the analysis by consensus. The methodological quality of included studies was assessed using the PEDro scale.

RESULTS

Fifty-four RCTs examining exercise interventions in patients with osteopenia or osteoporosis were included. A spectrum of facilitators and barriers to exercise for osteoporotic patients were identified; however, no one facilitator was more frequently reported than the other. The most commonly reported barriers were lack of time and transportation. In most RCTs, methods to promote and measure exercise adherence were unsatisfactory. Of the 54 papers, 72 % reported an adherence rate to an exercise program; the lowest reported rate was 51.7 %, and the highest 100 %.

CONCLUSIONS

Most RCTs found were of fair quality; however, less than three quarters identified facilitators and barriers to exercise. Reporting of methods to promote and measure exercise adherence were low. Future work should be directed toward identifying major facilitators and barriers to exercise adherence within RCTs. Only then can methods be identified to leverage facilitators and overcome barriers, thus strengthening the evidence for efficacy of optimal interventional exercise programs. This review has been registered in PROSPERO under registration number CRD42016039941.

Metabolomics and Its Application in the Development of Discovering Biomarkers for Osteoporosis Research

Osteoporosis is a progressive skeletal disorder characterized by low bone mass and increased risk of fracture in later life. The incidence and costs associated with treating osteoporosis cause heavy socio-economic burden. Currently, the diagnosis of osteoporosis mainly depends on bone mineral density and bone turnover markers. However, these indexes are not sensitive and accurate enough to reflect the osteoporosis progression. Metabolomics offers the potential for a holistic approach for clinical diagnoses and treatment, as well as understanding of the pathological mechanism of osteoporosis. In this review, we firstly describe the study subjects of osteoporosis and bio-sample preparation procedures for different analytic purposes, followed by illustrating the biomarkers with potentially predictive, diagnosis and pharmaceutical values when applied in osteoporosis research. Then, we summarize the published metabolic pathways related to osteoporosis. Furthermore, we discuss the importance of chronological data and combination of multi-omics in fully understanding osteoporosis. The application of metabolomics in osteoporosis could provide researchers the opportunity to gain new insight into the metabolic profiling and pathophysiological mechanisms. However, there is still much to be done to validate the potential biomarkers responsible for the progression of osteoporosis and there are still many details needed to be further elucidated.

Exercise as medicine - evidence for prescribing exercise as therapy in 26 different chronic diseases

This review provides the reader with the up-to-date evidence-based basis for prescribing exercise as medicine in the treatment of 26 different diseases: psychiatric diseases (depression, anxiety, stress, schizophrenia); neurological diseases (dementia, Parkinson's disease, multiple sclerosis); metabolic diseases (obesity, hyperlipidemia, metabolic syndrome, polycystic ovarian syndrome, type 2 diabetes, type 1 diabetes); cardiovascular diseases (hypertension, coronary heart disease, heart failure, cerebral apoplexy, and claudication intermittent); pulmonary diseases (chronic obstructive pulmonary disease, asthma, cystic fibrosis); musculo-skeletal disorders (osteoarthritis, osteoporosis, back pain, rheumatoid arthritis); and cancer. The effect of exercise therapy on disease pathogenesis and symptoms are given and the possible mechanisms of action are discussed. We have interpreted the scientific literature and for each disease, we provide the reader with our best advice regarding the optimal type and dose for prescription of exercise.

RELATIONSHIP BETWEEN TRAINING VOLUME AND BONE MINERAL DENSITY CHANGES IN ELDERLY WOMEN

ABSTRACT Introduction: Several studies have analyzed the relationship between physical activity and bone density. However, the prescription of exercise is not entirely clear as to the type, quantity and intensity. Objective: The objective of this study was to determine if there is a relationship between the amount of exercise and changes in bone mineral density. Methods: Fifty-two women, members of the Municipal Program of Physical Activity for Seniors, voluntarily underwent two ultrasonographies of the calcaneus within a 6-month interval. During this period, all physical activity was recorded. Afterwards, a lineal correlation study was carried out between the amount of exercise and bone changes, expressed as T-Score variation, first in total number of participants and then in groups. Considering the average body weight obtained for all women, two groups were created ("light" < 69 kg and "heavy" > 69 kg). Later, women who had participated in less than 72% of the targeted program were excluded from both groups, and the differences between the groups "light and trained" and "heavy and trained" were analyzed. To do so, the nonparametric Mann-Whitney U test was used. Results: A significant relationship of r= -0.59 was found between the total amount of exercise and the T-Score variation in the group of women above 69 kg. Significant differences were found between the "light and trained" group and the "heavy and trained" group with respect to the variation of T-Score. Conclusion: The effect of exercise on bone mineral density is determined, somehow, by body weight. This interaction is due, possibly, to mechanical demands difference.

Long-Term Exercise and Bone Mineral Density Changes in Postmenopausal Women--Are There Periods of Reduced Effectiveness?

There is increasing evidence that physical exercise can prevent fractures in postmenopausal women. However, even with careful adaptation of the exercise program to subjects' changing bone, health, and fitness status, effectivity may still decrease over the time. This could be specifically the case where the limitations of higher age collide with the specification of the exercise program. Thus, the aim of this study was to monitor bone mineral density (BMD) changes over a 16-year period of supervised exercise. Our hypothesis was that BMD differences at lumbar spine (LS) and femoral neck (FN) between exercisers (EG) and nontraining controls (CG) increased throughout the intervention with significant differences for each of the four 4-year observation periods. Sixty-seven (EG, n = 39 versus CG, n = 28) initially early-postmenopausal osteopenic women of the Erlangen Fitness and Osteoporosis Prevention Study (EFOPS) with complete BMD data sets for baseline (1998) and 4-, 8-, 12-, and 16-year follow-up were included in the analysis. The exercise protocol initially focused on a high-intensity strategy that addressed bone but increasingly shifted to a more comprehensive intervention. LS-BMD differences between the EG and CG continuously increased (year 4: 2.4% (95%- Confidence Interval 1.0% to 3.8%), year 8: 3.1% (1.6% to 4.7%), year 12: 3.9% (1.9% to 5.8), year 16: 4.5% (2.5% to 6.6%). Correspondingly, rising differences for FN-BMD (0.9% (-0.2% to 2.1%) versus 1.9% (0.4% to 3.3%) versus 2.0% (0.5% to 3.8%) versus 3.0% (1.0% to 5.0%)) were observed. However, in contrast to our hypothesis, group differences within the four 4-year periods were not consistently significant (LS, p = 0.001 to 0.097; FN, p = 0.026 to 0.673); further, BMD kinetics among the groups varied between LS and FN. Of particular importance, significant differences (p ≤ 0.030) for both regions were still found in the final period. We conclude that exercise-even when adapted for subjects' decreasing bone, health, and fitness status-is consistently effective in favorably affecting BMD in (initially) early-postmenopausal osteopenic women without any leveling-off effect after 16 years of exercise.

Atividade física na vida diária e densidade mineral óssea em mulheres idosas

INTRODUÇÃO: o rápido envelhecimento da população contemporânea tem influenciado no desenvolvimento de estratégias para a prevenção da osteoporose em idosos. A atividade física diária é vista como uma possível estratégia para aumentar a massa óssea e ajudar a prevenir a perda óssea em pessoas idosas. No entanto, é essencial saber a quantidade mínima ou a intensidade adequada de atividade física que produza o aumento da massa óssea em mulheres idosas.OBJETIVO: analisar, durante uma semana, a relação entre a quantidade e a intensidade da atividade física diária com a densidade mineral óssea (DMO) da mão, por meio da quantificação de atividade física diária em idosas.MÉTODOS: a amostra do estudo foi composta por 24 mulheres (idade 66-78 anos), que realizaram atividade física, durante 7 dias, com um gravador da aceleração dos movimentos do corpo em seu pulso, para uma quantificação individual da atividade física. Para medir a densidade mineral óssea da mão direita foi utilizada a técnica de dupla absorção de raios-X (DXA).RESULTADOS: uma relação significativa entre a prática semanal e o T-score (r = 0,99) e a prática semanal horizontal e o T-score (r = 0,99) foi encontrada no osso normal e no grupo ósseo com osteoporose, respectivamente. A relação entre T-score e a quantidade de atividade física não era clara em ambos os grupos.CONCLUSÃO: na amostra analisada, foi encontrada uma associação positiva entre a maior qualidade do osso da mão e a intensidade mais elevada de atividade física. A combinação de absorciometria acelerometria e de raios-X na mão obteve resultados semelhantes ao encontrados com outros métodos menos acessíveis.

Muscle strength, power and cardiorespiratory fitness are associated with bone mineral density in men aged 31-60 years

BACKGROUND

Osteoporotic fractures represent a growing economical burden to society, not only because of fractures in women, but also because of an increasing number of fractures in men.

AIMS

In this cross-sectional study we aimed to investigate the association of muscular and cardio-respiratory fitness with BMD at the spine and hip in men.

RESULTS

The association between independent variables maximal aerobic capacity (VO(2max)), leg power and hand grip strength, and dependent variables BMD at the spine and total hip was explored in a series of linear regression models successively adjusted for age, weight and height, smoking, alcohol intake and leisure time physical activity level. In the fully adjusted model we found a significant association of VO(2max) with BMD at the lumbar spine, p<0.0089. Furthermore, we observed significant associations of VO(2max) (p<0.0022) and leg power (p<0.011) with BMD at total hip.

CONCLUSIONS

We found that cardiorespiratory fitness was associated with BMD in men. Furthermore, hand grip strength and leg power were associated with increasing BMD at the lumbar spine and total hip in men, respectively. Further prospective studies are needed to further investigate the association between physical activity and BMD in men.

Moderate intensity resistive exercise improves metaphyseal cancellous bone recovery following an initial disuse period, but does not mitigate decrements during a subsequent disuse period in adult rats

Spaceflight provides a unique environment for skeletal tissue causing decrements in structural and densitometric properties of bone. Previously, we used the adult hindlimb unloaded (HU) rat model to show that previous exposure to HU had minimal effects on bone structure after a second HU exposure followed by recovery. Furthermore, we found that the decrements during second HU exposure were milder than the initial HU cycle. In this study, we used a moderate intensity resistance exercise protocol as an anabolic stimulus during recovery to test the hypothesis that resistance exercise following an exposure to HU will significantly enhance recovery of densitometric, structural, and, more importantly, mechanical properties of trabecular and cortical bone. We also hypothesized that resistance exercise during recovery, and prior to the second unloading period, will mitigate the losses during the second exposure. The hypothesis that exercise during recovery following hindlimb unloading will improve bone quality was supported by our data, as total BMC, total vBMD, and cancellous bone formation at the proximal tibia metaphysis increased significantly during exercise period, and total BMC/vBMD exceeded age-matched control and non-exercised values significantly by the end of recovery. However, our results did not support the hypothesis that resistance exercise prior to a subsequent unloading period will mitigate the detrimental effects of the second exposure, as the losses during the second exposure in total BMC, total vBMD, and cortical area at the proximal tibia metaphysis for the exercised animals were similar to those of the non-exercised group. Therefore, exercise did not mitigate effects of the second HU exposure in terms of pre-to-post HU changes in these variables, but it did produce beneficial effects in a broader sense.

Running exercise alleviates trabecular bone loss and osteopenia in hemizygous β-globin knockout thalassemic mice

A marked decrease in β-globin production led to β-thalassemia, a hereditary anemic disease associated with bone marrow expansion, bone erosion, and osteoporosis. Herein, we aimed to investigate changes in bone mineral density (BMD) and trabecular microstructure in hemizygous β-globin knockout thalassemic (BKO) mice and to determine whether endurance running (60 min/day, 5 days/wk for 12 wk in running wheels) could effectively alleviate bone loss in BKO mice. Both male and female BKO mice (1-2 mo old) showed growth retardation as indicated by smaller body weight and femoral length than their wild-type littermates. A decrease in BMD was more severe in female than in male BKO mice. Bone histomorphometry revealed that BKO mice had decreases in trabecular bone volume, trabecular number, and trabecular thickness, presumably due to suppression of osteoblast-mediated bone formation and activation of osteoclast-mediated bone resorption, the latter of which was consistent with elevated serum levels of osteoclastogenic cytokines IL-1α and -1β. As determined by peripheral quantitative computed tomography, running increased cortical density and thickness in the femoral and tibial diaphyses of BKO mice compared with those of sedentary BKO mice. Several histomorphometric parameters suggested an enhancement of bone formation (e.g., increased mineral apposition rate) and suppression of bone resorption (e.g., decreased osteoclast surface), which led to increases in trabecular bone volume and trabecular thickness in running BKO mice. In conclusion, BKO mice exhibited pervasive osteopenia and impaired bone microstructure, whereas running exercise appeared to be an effective intervention in alleviating bone microstructural defect in β-thalassemia.

Effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone and N-terminal telopeptide in the postmenopausal women

Menopause is characterized by rapid decreases in bone mineral density, aerobic fitness, muscle strength, and balance. In the present study, we investigated the effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone (FSH) and N-terminal telopeptide (NTX) in the postmenopausal women. Subjects were consisted of 20 postmenopausal women, who had not menstruated for at least 1 yr and had follicle-stimulating hormone levels > 35 mIU/L, estradiol levels< 40 pg/mL. The subjects were randomly divided into two groups: control group (n= 10), new sports tennis type exercise group (n= 10). New sports tennis type exercise was consisted of warm up (10 min), new sports tennis type exercise (40 min), cool down (10 min) 3 days a per week for 12 weeks. The aerobic capacities were increased by 12 weeks new sports tennis type exercise. New sports tennis type exercise significantly increased FSH and NTx levels, indicating biochemical markers of bone formation and resorption. These findings indicate that 12 weeks of new sports tennis type exercise can be effective in prevention of bone loss and enhancement of aerobic capacity in postmenopausal women.

Too Fit To Fracture: exercise recommendations for individuals with osteoporosis or osteoporotic vertebral fracture

SUMMARY

A consensus process was conducted to develop exercise recommendations for individuals with osteoporosis or vertebral fractures. A multicomponent exercise program that includes balance and resistance training is recommended.

INTRODUCTION

The aim was to develop consensus on exercise recommendations for older adults: (1) with osteoporosis and (2) with osteoporotic vertebral fracture(s).

METHODS

The Grading of Recommendations Assessment, Development, and Evaluation method was used to evaluate the quality of evidence and develop recommendations. Outcomes important for decision making were nominated by an expert panel and patient advocates. They included falls, fractures, bone mineral density (BMD), and adverse events for individuals with osteoporosis/vertebral fractures, and pain, quality of life, and function for those with vertebral fracture. Meta-analyses evaluating the effects of exercise on the outcomes were reviewed. Observational studies or clinical trials were reviewed when meta-analyses were not available. Quality ratings were generated, and informed the recommendations.

RESULTS

The outcome for which evidence is strongest is falls. Point estimates of the effects of exercise on falls, fractures, and BMD vary according to exercise type. There is not enough evidence to quantify the risks of exercise in those with osteoporosis or vertebral fracture. Few trials of exercise exist in those with vertebral fracture. The exercise recommendations for exercise in individuals with osteoporosis or osteoporotic vertebral fracture are conditional. The panel strongly recommends a multicomponent exercise program including resistance and balance training for individuals with osteoporosis or osteoporotic vertebral fracture. The panel recommends that older adults with osteoporosis or vertebral fracture do not engage in aerobic training to the exclusion of resistance or balance training.

CONCLUSIONS

The consensus of our international panel is that exercise is recommended for older adults with osteoporosis or vertebral fracture, but our recommendations are conditional.

Canadian Academy of Sport and Exercise Medicine position statement: osteoporosis and exercise

The purpose of this paper is to look at the effects of exercise in the treatment and prevention of osteoporosis in athletes of all age groups. Recommendations for exercise programs will be discussed as a tool to improve bone health. Medical management of osteoporosis will be reviewed mainly as it pertains to postmenopausal women.

Mechanical stimulation of polycystin-1 induces human osteoblastic gene expression via potentiation of the calcineurin/NFAT signaling axis

Mechanical forces trigger biological responses in bone cells that ultimately control osteoblastogenesis and bone program. Although several mechanosensors have been postulated, the precise mechanotransduction pathway remains obscure as the initial mechanosensing event has not yet been identified. Studies in kidney cells have shown that polycystin-1 (PC1), via its extracellular N-terminal part, may function as an "antenna-like" protein providing a linkage between environmental cues and their conversion into biochemical responses that regulate various cellular processes via the calcineurin/NFAT pathway. Here we explored the involvement of PC1 in mechanical load (stretching)-induced signaling cascades that control osteoblastogenesis/bone formation. FACS and TransAM Transcription Factor ELISA analyses employing extracts from primary human osteoblast-like, PC1 expressing cells subjected to mechanical stretching (0-6 h) revealed that unphosphorylated/DNA-binding competent NFATc1 increased at 0.5-1 h and returned to normal at 6 h. In accordance with the activation mechanism of NFATc1, stretching of cultured cells pre-treated with cyclosporin A (CsA, a specific inhibitor of the calcineurin/NFAT pathway) abrogated the observed decrease in the abundance of the cytoplasmic pNFATc1 (phosphorylated/inactive) species. Furthermore, stretching of osteoblastic cells pre-treated with an antibody against the mechanosensing N-terminal part of PC1 also abrogated the observed decrease in the cytoplasmic levels of the inactive pNFATc1 species. Importantly, under similar conditions (pre-incubation of stretched cells with the inhibitory anti-PC1 antibody), the expression of the key osteoblastic, NFATc1-target gene runx2 decreased compared to untreated cells. Therefore, PC1 acts as chief mechanosensing molecule that modulates osteoblastic gene transcription and hence bone-cell differentiation through the calcineurin/NFAT signaling cascade.

Effects of ground and joint reaction force exercise on lumbar spine and femoral neck bone mineral density in postmenopausal women: a meta-analysis of randomized controlled trials

Background

Low bone mineral density (BMD) and subsequent fractures are a major public health problem in postmenopausal women. The purpose of this study was to use the aggregate data meta-analytic approach to examine the effects of ground (for example, walking) and/or joint reaction (for example, strength training) exercise on femoral neck (FN) and lumbar spine (LS) BMD in postmenopausal women.

Methods

The a priori inclusion criteria were: (1) randomized controlled trials, (2) exercise intervention ≥ 24 weeks, (3) comparative control group, (4) postmenopausal women, (5) participants not regularly active, i.e., less than 150 minutes of moderate intensity (3.0 to 5.9 metabolic equivalents) weight bearing endurance activity per week, less than 75 minutes of vigorous intensity (> 6.0 metabolic equivalents) weight bearing endurance activity per week, resistance training < 2 times per week, (6) published and unpublished studies in any language since January 1, 1989, (7) BMD data available at the FN and/or LS. Studies were located by searching six electronic databases, cross-referencing, hand searching and expert review. Dual selection of studies and data abstraction were performed. Hedge’s standardized effect size (g) was calculated for each FN and LS BMD result and pooled using random-effects models. Z-score alpha values, 95%confidence intervals (CI) and number-needed-to-treat (NNT) were calculated for pooled results. Heterogeneity was examined using Q and I². Mixed-effects ANOVA and simple meta-regression were used to examine changes in FN and LS BMD according to selected categorical and continuous variables. Statistical significance was set at an alpha value ≤0.05 and a trend at >0.05 to ≤ 0.10.

Results

Small, statistically significant exercise minus control group improvements were found for both FN (28 g’s, 1632 participants, g = 0.288, 95% CI = 0.102, 0.474, p = 0.002, Q = 90.5, p < 0.0001, I² = 70.1%, NNT = 6) and LS (28 g’s, 1504 participants, g = 0.179, 95% CI = −0.003, 0.361, p = 0.05, Q = 77.7, p < 0.0001, I² = 65.3%, NNT = 6) BMD. Clinically, it was estimated that the overall changes in FN and LS would reduce the 20-year relative risk of osteoporotic fracture at any site by approximately 11% and 10%, respectively. None of the mixed-effects ANOVA analyses were statistically significant. Statistically significant, or a trend for statistically significant, associations were observed for changes in FN and LS BMD and 20 different predictors.

Conclusions

The overall findings suggest that exercise may result in clinically relevant benefits to FN and LS BMD in postmenopausal women. Several of the observed associations appear worthy of further investigation in well-designed randomized controlled trials.

Effects of training on bone mass in older adults: a systematic review

It is widely recognized that the risk of fractures is closely related to the typical decline in bone mass during the ageing process in both women and men. Exercise has been reported as one of the best non-pharmacological ways to improve bone mass throughout life. However, not all exercise regimens have the same positive effects on bone mass, and the studies that have evaluated the role of exercise programmes on bone-related variables in elderly people have obtained inconclusive results. This systematic review aims to summarize and update present knowledge about the effects of different types of training programmes on bone mass in older adults and elderly people as a starting point for developing future interventions that maintain a healthy bone mass and higher quality of life in people throughout their lifetime. A literature search using MEDLINE and the Cochrane Central Register of Controlled Trials databases was conducted and bibliographies for studies discussing the effect of exercise interventions in older adults published up to August 2011 were examined. Inclusion criteria were met by 59 controlled trials, 7 meta-analyses and 8 reviews. The studies included in this review indicate that bone-related variables can be increased, or at least the common decline in bone mass during ageing attenuated, through following specific training programmes. Walking provides a modest increase in the loads on the skeleton above gravity and, therefore, this type of exercise has proved to be less effective in osteoporosis prevention. Strength exercise seems to be a powerful stimulus to improve and maintain bone mass during the ageing process. Multi-component exercise programmes of strength, aerobic, high impact and/or weight-bearing training, as well as whole-body vibration (WBV) alone or in combination with exercise, may help to increase or at least prevent decline in bone mass with ageing, especially in postmenopausal women. This review provides, therefore, an overview of intervention studies involving training and bone measurements among older adults, especially postmenopausal women. Some novelties are that WBV training is a promising alternative to prevent bone fractures and osteoporosis. Because this type of exercise under prescription is potentially safe, it may be considered as a low impact alternative to current methods combating bone deterioration. In other respects, the ability of peripheral quantitative computed tomography (pQCT) to assess bone strength and geometric properties may prove advantageous in evaluating the effects of training on bone health. As a result of changes in bone mass becoming evident by pQCT even when dual energy X-ray absortiometry (DXA) measurements were unremarkable, pQCT may provide new knowledge about the effects of exercise on bone that could not be elucidated by DXA. Future research is recommended including longest-term exercise training programmes, the addition of pQCT measurements to DXA scanners and more trials among men, including older participants.

Characterizing the role of mechanical signals in gene regulatory networks using Long SAGE

A systems understanding of mechanical regulation is critical for determining how cells proliferate and differentiate. To better understand the biological process in which mechanical signals regulate cells, we globally investigated the gene expression profiling via long serial analysis of gene expression (Long SAGE) in osteoblasts after exposure to mechanical stretching. The analysis showed that the differentially expressed genes were related with many physiological processes, including signal transduction, cell proliferation and apoptosis. Several genes that were seldom or never studied in osteoblasts have been found in this study. We further analyzed the signal pathways and provided gene regulatory networks activated by mechanical signals. Many changed genes in our data were contributed to ECM-integrin-FAK mediated pathway and mainly influenced actin-cytoskeleton dynamic remodeling, cell proliferation and differentiation. We also provided evidence supporting the hypothesis that endoplasmic reticulum and mitochondrion were combined to dedicate to calcium regulation. Taken together, our experiments provided a systemic view on biological processes and mechanotransduction network in osteoblasts, suggesting that mechanical signals regulate osteoblast through a greater diversity of interactions and pathways than previously appreciated.

A systematic review of the effectiveness of lifestyle interventions for improving bone health in women at high risk of osteoporosis

BACKGROUND

Osteoporosis is a disease characterised by low bone mass and microarchitectural deterioration of bone tissue, leading to increased bone fragility and a consequent increase in fracture risk, especially among postmenopausal women. Management strategies for osteoporosis focus on reducing modifiable risk factors such as poor nutrition, insufficient physical activity, smoking, and heavy alcohol consumption.

OBJECTIVE

The aim of this systematic review is to examine the effects of lifestyle interventions on bone health in women at high risk of osteoporosis INCLUSION CRITERIA: We included randomised controlled trials that examined the effectiveness of lifestyle interventions. The participants consisted of adult women who have had osteoporosis, osteopenia, or were at high-risk of developing osteoporosis. Lifestyle interventions included exercise, diet, and education. The outcomes of bone health were bone mineral density, event (fall, fracture), balance, and quality of life.

SEARCH STRATEGY

We conducted a comprehensive search of the published literature using a three-phase approach in English and Korean languages up until September 2009.

METHODOLOGICAL QUALITY

Two independent reviewers appraised all reports using standardised critical appraisal tools from the Joanna Briggs Institute that were specific to experimental research designs.

DATA COLLECTION

Quantitative data was extracted from papers using the standardised data extraction tool from Joanna Briggs Institute.

DATA SYNTHESIS

Quantitative papers were pooled wherever possible to a statistical meta-analysis using the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument.

RESULTS

The search identified 700 unique studies; we appraised 28 studies and included a total of 25 randomised controlled trials in the final study; three studies were excluded because of poor methodological quality. Strength exercises had a positive effect on fracture. Aerobic exercises had a positive impact on lumbar bone mineral density, fall, and balance. Soy protein supplementation was effective for improving lumbar bone mineral density while vitamin K supplementation had a positive effect on of femur bone mineral density. Calcium supplementation had a positive impact on femur and lumbar bone mineral density. The combination of exercise, calcium, and vitamin D supplementation was effective for improving lumbar bone mineral density, risk of fall, and balance. Self-management programs for better bone health had a positive effect on balance and quality of life.

CONCLUSION

The results indicate that lifestyle interventions including exercise and taking daily calcium and vitamin D supplementation are beneficial for improving bone health in women at high risk of osteoporosis. However, additional carefully designed randomised controlled trials studies with larger patient populations are needed to more precisely identify the effects of intervention.

IMPLICATIONS FOR PRACTICE

It is recommended to engage in a combination of regular exercise and daily calcium and vitamin D supplementation with consideration of age, menopausal status, and bone mineral density for women with a high risk of developing osteoporosis.

IMPLICATIONS FOR RESEARCH

Effects of combined intervention of lifestyle components should be evaluated in large, carefully designed randomised controlled trials.

Non-uniform decay in jumping exercise-induced bone gains following 12 and 24 weeks of cessation of exercise in rats

The effects of deconditioning on exercise-induced bone gains in rats were investigated in 12-week-old female WKY rats performing a standard jumping exercise regimen for either 8, 12 or 24 weeks, followed by sedentary periods of either 24, 12 or 0 weeks, respectively. Age-matched controls received no exercise over the same period. At the end of the training/sedentary period, the tibiae were harvested for analyses of bone parameters. Gains in tibial fat-free dry weight decayed within 12 weeks of deconditioning, but gains in tibial ultimate bending force (strength), maximum diameter and cortical area were still present at 12 weeks of deconditioning. With the exception of cortical area, all other exercise-induced bone gains decayed by the 24th week of deconditioning. It appears that the decay in exercise-induced bone gains in strength, physical and morphological properties is not uniform, and that gains in fat-free dry weight seem to decay earlier.

Long-term aerobic exercise and omega-3 supplementation modulate osteoporosis through inflammatory mechanisms in post-menopausal women: a randomized, repeated measures study

BACKGROUND

Evidence indicates that dietary fats and physical activity influence bone health. The purpose of this study was to examine the effects of long-term aerobic exercise and omega-3 (N-3) supplementation on serum inflammatory markers, bone mineral density (BMD), and bone biomarkers in post-menopausal women.

METHODS

Seventy-nine healthy sedentary post-menopausal women aged 58-78 years participated in this study. Subjects were randomized to one of 4 groups: exercise + supplement (E+S, n = 21), exercise (E, n = 20), supplement (S, n = 20), and control (Con, n = 18) groups. The subjects in the E+S and E groups performed aerobic exercise training (walking and jogging) up to 65% of HRmax, three times a week for 24 weeks. Subjects in the E+S and S groups consumed 1000 mg/d N-3 for 24 weeks. The lumbar spine (L2-L4) and femoral neck BMD, serum tumor necrosis factor (TNF) α, interleukin (IL) 6, prostaglandin (PG) E2, estrogen, osteocalcin, 1, 25-dihydroxyvitamin D3 (1, 25 Vit D), C-telopeptide (CTX), parathyroid hormone (PTH) and calcitonin (CT) were measured at baseline, the end of week 12 and 24.

RESULTS

Serum estrogen, osteocalcin, 1, 25 Vit D, CT, L2-L4 and femoral neck BMD measures increased (P < 0.05) and the serum CTX, PTH, TNF-α, IL-6, and PGE2 decreased (P < 0.05) in E + S group after the 24 wk intervention but not in the E or S intervention groups. L2-L4 and femoral neck BMD, estrogen, osteocalcin, and CT were negatively (P < 0.05) correlated with TNF-α and PGE2. PTH and CT were correlated positively and negatively with IL-6, respectively (P < 0.05).

CONCLUSIONS

The present study demonstrates that long-term aerobic exercise training plus N-3 supplementation have a synergistic effect in attenuating inflammation and augmenting BMD in post-menopausal osteoporosis.

Endurance exercise training promotes medullary hematopoiesis

Endurance exercise is a poorly defined yet powerful mediator of hematopoiesis. The purpose of this study was to directly investigate the effects of endurance exercise training on hematopoiesis and to identify potential mechanisms responsible for any observed changes. Four-week-old male C57Bl/6 mice were trained on a treadmill at progressive speeds over a 10-wk period. Tissues were harvested 2 d following the final training session. Flow cytometry, the cobblestone area-forming cell assay, and the methycellulose colony-forming unit assay were used to assess medullary and mobilized hematopoietic stem and progenitor cells. Quantitative real-time PCR and Western blots were used to measure hematopoietic cytokine production. Histochemistry was also used to assess adaptations to exercise in the bone marrow niche. Depending on the cell type, endurance training increased medullary and mobilized hematopoietic stem and progenitor cell content from 50 to 800%. Training also reduced marrow cavity fat by 78%. Skeletal muscle hematopoietic cytokine expression was also increased at least 60% by training. Sedentary mice served as controls for the above experiments. In conclusion, endurance exercise training greatly promotes hematopoiesis and does so through improvements in medullary niche architecture as well as increased skeletal muscle hematopoietic cytokine production.

Exercise for preventing and treating osteoporosis in postmenopausal women

BACKGROUND

Osteoporosis is a condition resulting in an increased risk of skeletal fractures due to a reduction in the density of bone tissue. Treatment of osteoporosis typically involves the use of pharmacological agents. In general it is thought that disuse (prolonged periods of inactivity) and unloading of the skeleton promotes reduced bone mass, whereas mechanical loading through exercise increases bone mass.

OBJECTIVES

To examine the effectiveness of exercise interventions in preventing bone loss and fractures in postmenopausal women.

SEARCH STRATEGY

During the update of this review we updated the original search strategy by searching up to December 2010 the following electronic databases: the Cochrane Musculoskeletal Group's Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2010 Issue 12); MEDLINE; EMBASE; HealthSTAR; Sports Discus; CINAHL; PEDro; Web of Science; Controlled Clinical Trials; and AMED. We attempted to identify other studies by contacting experts, searching reference lists and searching trial registers.

SELECTION CRITERIA

All randomised controlled trials (RCTs) that met our predetermined inclusion criteria.

DATA COLLECTION AND ANALYSIS

Pairs of members of the review team extracted the data and assessed trial quality using predetermined forms. For dichotomous outcomes (fractures), we calculated risk ratios (RRs) using a fixed-effect model. For continuous data, we calculated mean differences (MDs) of the percentage change from baseline. Where heterogeneity existed (determined by the I(2) statistic), we used a random-effects model.

MAIN RESULTS

Forty-three RCTs (27 new in this update) with 4320 participants met the inclusion criteria. The most effective type of exercise intervention on bone mineral density (BMD) for the neck of femur appears to be non-weight bearing high force exercise such as progressive resistance strength training for the lower limbs (MD 1.03; 95% confidence interval (CI) 0.24 to 1.82). The most effective intervention for BMD at the spine was combination exercise programmes (MD 3.22; 95% CI 1.80 to 4.64) compared with control groups. Fractures and falls were reported as adverse events in some studies. There was no effect on numbers of fractures (odds ratio (OR) 0.61; 95% CI 0.23 to 1.64). Overall, the quality of the reporting of studies in the meta-analyses was low, in particular in the areas of sequence generation, allocation concealment, blinding and loss to follow-up.

AUTHORS' CONCLUSIONS

Our results suggest a relatively small statistically significant, but possibly important, effect of exercise on bone density compared with control groups. Exercise has the potential to be a safe and effective way to avert bone loss in postmenopausal women.

Exercise interventions to reduce fall-related fractures and their risk factors in individuals with low bone density: a systematic review of randomized controlled trials

SUMMARY

Exercise can reduce falls and fall-related fractures in healthy individuals; however, evidence for individuals with low BMD is limited. The results from this systematic review indicate that exercise interventions for individuals with low BMD to reduce falls and fractures should include balance, muscle strengthening, and weight-bearing exercises.

INTRODUCTION

The purpose of this systematic review was to investigate which exercise interventions are effective in individuals with low bone mineral density (BMD; osteopenia or osteoporosis) in reducing (1) falls and fractures and (2) risk factors for falls and fractures.

METHODS

Databases were searched for relevant studies between 1996 and June 2008. Methodological quality was assessed with the Jadad score and the PEDro scale.

RESULTS

Of the 1,369 publications found, 23 met the inclusion criteria. Five additional articles were included after checking reference lists and searching author's names and related articles. Interventions with balance exercises reduced falls or fall-related fractures and improved balance in the majority of the studies. Muscle strengthening exercises were effective in improving lower extremity strength and back extensor strength; however, not all RCT's reported positive effects. Bone strength was improved by weight-bearing aerobic exercise with or without muscle strengthening exercise when the duration of the intervention was at least a year.

CONCLUSIONS

Exercise can reduce falls, fall-related fractures, and several risk factors for falls in individuals with low BMD. Exercise interventions for patients with osteoporosis should include weight-bearing activities, balance exercise, and strengthening exercises to reduce fall and fracture risk.

Minimum level of jumping exercise required to maintain exercise-induced bone gains in female rats

SUMMARY

This study determines the minimum level of exercise required to maintain 8 weeks of jumping exercise-induced bone gains in rats. It was found that the minimum level of exercise required for maintaining the different exercise-induced bone gains varied between 11% and 18% of the initial exercise intensity.

INTRODUCTION

This study ascertains the minimum level of follow-up exercise required to maintain bone gains induced by an 8-week jumping exercise in rats.

METHODS

Twelve groups of 12-week old rats (n = 10 rats per group) were given either no exercise for 8 (8S) or 32 weeks (32S), or received 8 weeks of standard training program (8STP) that consisted of 200 jumps per week, given at 40 jumps per day for 5 days per week, followed by 24 weeks of exercise at loads of either 40 or 20 or 10 jumps per day, for either 5, or 3, or 1 day/week. Bone mass, strength, and morphometric properties were measured in the right tibia. Data were analyzed using one-way analyses of variance.

RESULTS

Bone mass, strength, mid-shaft periosteal perimeter and cortical area were significantly (p < 0.05) higher in the rats given 8STP than that in the 8S group. The minimal level of exercise required to maintain the bone gains was 31, 36, 25, and 21 jumps per week for mass, strength, periosteal perimeter and cortical area, respectively.

CONCLUSIONS

Eight weeks of jumping exercise-induced bone gains could be maintained for a period of 24 weeks with follow-up exercise consisting of 11% to 18% of the initial exercise load.

Mechanotransduction in osteoblast regulation and bone disease

Osteoblasts are key components of the bone multicellular unit and have a seminal role in bone remodeling, which is an essential function for the maintenance of the structural integrity and metabolic capacity of the skeleton. The coordinated function of skeletal cells is regulated by several hormones, growth factors and mechanical cues that act via interconnected signaling networks, resulting in the activation of specific transcription factors and, in turn, their target genes. Bone cells are responsive to mechanical stimuli and this is of pivotal importance in developing biomechanical strategies for the treatment of osteodegenerative diseases. Here, we review the molecular pathways and players activated by mechanical stimulation during osteoblastic growth, differentiation and activity in health, and consider the role of mechanostimulatory approaches in treating various bone pathophysiologies.

Maintenance of exercise-induced benefits in physical functioning and bone among elderly women

SUMMARY

This study showed that about a half of the exercise-induced gain in dynamic balance and bone strength was maintained one year after cessation of the supervised high-intensity training of home-dwelling elderly women. However, to maintain exercise-induced gains in lower limb muscle force and physical functioning, continued training seems necessary.

INTRODUCTION

Maintenance of exercise-induced benefits in physical functioning and bone structure was assessed one year after cessation of 12-month randomized controlled exercise intervention.

METHODS

Originally 149 healthy women 70-78 years of age participated in the 12-month exercise RCT and 120 (81%) of them completed the follow-up study. Self-rated physical functioning, dynamic balance, leg extensor force, and bone structure were assessed.

RESULTS

During the intervention, exercise increased dynamic balance by 7% in the combination resistance and balance-jumping training group (COMB). At the follow-up, a 4% (95% CI: 1-8%) gain compared with the controls was still seen, while the exercise-induced isometric leg extension force and self-rated physical functioning benefits had disappeared. During the intervention, at least twice a week trained COMB subjects obtained a significant 2% benefit in tibial shaft bone strength index compared to the controls. A half of this benefit seemed to be maintained at the follow-up.

CONCLUSIONS

Exercise-induced benefits in dynamic balance and rigidity in the tibial shaft may partly be maintained one year after cessation of a supervised 12-month multi-component training in initially healthy elderly women. However, to maintain the achieved gains in muscle force and physical functioning, continued training seems necessary.