Effect of exercise training combined with isoflavone supplementation on bone and lipids in postmenopausal women: a randomized clinical trial

Effects of exercise on bone density and physical performance in postmenopausal women: A systematic review and meta-analysis

BACKGROUND

Postmenopausal bone loss and decreased physical performance are commonly presented issues. This study aimed through systematic review and meta-analysis to examine the benefits of adding exercise to medicine/supplements in postmenopausal women.

METHODS

A systematic search was conducted of four electronic databases for articles published from inception to December 2023. Clinical controlled trials comparing the effect of additional exercise and medicine/supplements alone in postmenopausal women were included. The outcomes studied were bone mineral density (BMD) and physical performance. The quality of evidence was evaluated by the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

RESULTS

Nineteen articles with 1249 participants were included in this study for systematic review and meta-analysis. The results showed that additional exercise was not associated with significantly improved BMD at the lumbar spine and hip joint compared with medicine/supplements only. However, results of subgroup analysis of exercise types showed a significant improvement in lumbar spine BMD by combining multiple types of exercise training (SMD = 0.37; 95% confidence interval [CI] = 0.01-0.72; p = .04). Furthermore, additional exercise significantly improved lower extremity muscle strength (Standard Mean Difference [SMD] = 1.77; 95% CI = 0.56-2.98; p = .004), Berg's Balance Scale (SMD = 0.72; 95% CI = 0.12-1.32; p = .02), Timed Up and Go (SMD = -1.07; 95% CI = -1.35--0.78; p < .001), fear of falling (SMD = 1.32; 95% CI = 0.89-1.75; p < .001), and the quality of life (SMD = 1.39; 95% CI = 0.74-2.05; p < .001). The quality level of the evidence was between low to very low.

CONCLUSIONS

The significant value of the exercise was demonstrated through enhancing physical performance and quality of life. Moreover, combining various exercise training programs has shown a positive effect on BMD at the lumbar spine. Therefore, for postmenopausal women, combining exercise with medicine/supplements is recommended to further improve physical function and specific areas of BMD. (PROSPERO: CRD42023390633).

Effect of soy isoflavone supplementation on blood pressure: a meta-analysis of randomized controlled trials

BACKGROUND

Previous experimental studies have suggested that the consumption of soy isoflavones may have a potential impact on lowering blood pressure. Nevertheless, epidemiological studies have presented conflicting outcomes concerning the correlation between soy isoflavone consumption and blood pressure levels. Consequently, a comprehensive meta-analysis of all eligible randomized controlled trials (RCTs) was conducted to explore the influence of soy isoflavones on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults.

METHODS

A thorough search of PubMed, Embase, and the Cochrane Library for relevant literature up to April 30, 2023 was conducted. RCTs involving adults that compared soy isoflavone supplementation with a placebo (the same matrix devoid of soy isoflavone) were included. The combined effect size was presented as the weighted mean difference (WMD) along with 95% confidence interval (CI), employing a fixed-effects model.

RESULTS

Our meta-analysis included a total of 24 studies involving 1945 participants. The results revealed a significant reduction in both SBP and DBP with soy isoflavone supplementation. Subgroup analyses suggested more pronounced reductions in SBP and DBP for interventions lasting ≥6 months, in individuals receiving mixed-type soy isoflavone, and among patients with metabolic syndrome or prehypertension. However, we did not detect significant nonlinear associations between supplementation dosage and intervention duration concerning both SBP and DBP. The overall quality of evidence was deemed moderate.

CONCLUSIONS

The current meta-analysis revealed that supplementation with soy isoflavones alone effectively reduces blood pressure. Additional high-quality studies are required to investigate the efficacy of blood pressure reduction through supplementation with an optimal quantity and proportion of soy isoflavone.

Isoflavone intervention and its impact on bone mineral density in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials

Due to estrogen deficiency, postmenopausal women may suffer from an imbalance in bone metabolism that leads to bone fractures. Isoflavones, a type of phytoestrogen, have been suggested to improve bone metabolism and increase bone mass. Therefore, isoflavones are increasingly recognized as a promising natural alternative to hormone replacement therapy for postmenopausal women who face a heightened risk of osteoporosis and are susceptible to bone fractures.

PURPOSE

This study aimed to evaluate the efficacy of isoflavone interventions on bone mineral density (BMD) in postmenopausal women by means of systematic review and meta-analysis.

METHODS

The electronic database searches were performed on PubMed, Embase, Scopus, and Cochrane Library databases, covering literature up to April 20, 2023. A random-effects model was used to obtain the main effect estimates, with a mean difference (MD) and its 95% confidence interval (CI) as the effect size summary. The risk of bias assessment was conducted using the Risk of Bias 2 (RoB2) tool.

RESULTS

A total of 63 randomized controlled trials comparing isoflavone interventions (n = 4,754) and placebo (n = 4,272) were included. The results indicated that isoflavone interventions significantly improved BMD at the lumbar spine (MD = 0.0175 g/cm2; 95% CI, 0.0088 to 0.0263, P < 0.0001), femoral neck (MD = 0.0172 g/cm2; 95% CI, 0.0046 to 0.0298, P = 0.0073), and distal radius (MD = 0.0138 g/cm2; 95% CI, 0.0077 to 0.0198, P < 0.0001) in postmenopausal women. Subgroup analysis showed that the isoflavone intervention was effective for improving BMD when the duration was ≥ 12 months and when the intervention contained genistein of at least 50 mg/day.

CONCLUSION

This systematic review and meta-analysis suggests that isoflavone interventions, especially those containing genistein of at least 50 mg/day, can effectively enhance BMD in postmenopausal women.

Effect of Unfermented Soy Product Consumption on Blood Lipids in Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Clinical studies have reported the beneficial effects of unfermented soy product consumption on blood lipids in various populations. However, contradictory results have been reported regarding the influence of unfermented soy product consumption on blood lipids in postmenopausal women.

OBJECTIVE

The aim of this systematic review and meta-analysis was to evaluate the effects of diets with unfermented soy products compared with diets without unfermented soy products on blood lipids in postmenopausal women.

METHODS

The Cochrane Library, PubMed, Scopus, Web of Science, and Embase electronic databases were searched for eligible randomized controlled trials (RCTs) published up to February 21, 2023. RCTs were included if they were published in English and investigated the effect of unfermented soy product consumption on blood lipids in postmenopausal women who had discontinued hormone replacement therapy at least 3 months before randomization. A random-effects model was used to calculate the overall effect size of the mean difference (MD) and 95% CI. Risk of bias was assessed using the Cochrane Risk-of-Bias Tool for Randomized Trials, version 2.

RESULTS

Twenty-nine RCTs involving 2,457 participants were included. The results showed that, compared with the control group that did not consume unfermented soy products, consumption of unfermented soy products significantly reduced total cholesterol (TC) (MD, -9.46 mg/dL [to convert mg/dL cholesterol to mmol/L, multiply mg/dL by 0.0259; to convert mmol/L cholesterol to mg/dL, multiply by 38.7]; 95% CI -15.04 to -3.89 mg/dL; P = .001) and triglycerides (TGs) (MD, -10.86 mg/dL [to convert mg/dL TGs to mmol/L, multiply mg/dL by 0.0113; to convert mmol/L TGs to mg/dL, multiply mmol/L by 88.6]; 95% CI -19.70 to -2.02 mg/dL; P = .016), while significantly increasing high-density lipoprotein cholesterol (MD, 2.32 mg/dL; 95% CI 0.87 to 3.76 mg/dL; P = .002) in postmenopausal women, but had no significant effect on low-density lipoprotein cholesterol (MD, -4.55 mg/dL; 95% CI -10.90 to 1.80 mg/dL; P = .160). Results of soy preparation subgroup analysis showed that soy isolate protein significantly reduced TC and soy protein-containing isoflavones significantly reduced TC and low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol. Furthermore, unfermented soy product consumption significantly reduced TC, low-density lipoprotein cholesterol, and TG levels in postmenopausal women with lipid disorders and TGs in healthy postmenopausal women.

CONCLUSIONS

The results showed that unfermented soy product consumption reduced TC and TG levels significantly, and increased high-density lipoprotein cholesterol levels in postmenopausal women. The findings of this review contribute to the evidence-base for dietary management of blood lipids in postmenopausal women.

Effects of Isoflavonoid and Vitamin D Synergism on Bone Mineral Density-A Systematic and Critical Review

Phytoestrogens are non-steroidal plant compounds, which bind to α and β estrogen receptors, thereby causing specific effects. The best-known group of phytoestrogens are flavonoids, including isoflavonoids-genistein and daidzein. They play a role in the metabolism of bone tissue, improving its density and preventing bone loss, which contributes to reducing the risk of fractures. Vitamin D is found in the form of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) and is traditionally recognized as a regulator of bone metabolism. The aim of this review was to evaluate the synergistic effect of isoflavonoids and vitamin D on bone mineral density (BMD). The MEDLINE (PubMed), Scopus and Cochrane databases were searched independently by two authors. The search strategy included controlled vocabulary and keywords. Reference publications did not provide consistent data regarding the synergistic effect of isoflavonoids on BMD. Some studies demonstrated a positive synergistic effect of these compounds, whereas in others, the authors did not observe any significant differences. Therefore, further research on the synergism of isoflavonoids and vitamin D may contribute to a significant progress in the prevention and treatment of osteoporosis.

Finding the Optimal Resistance Training Intensity for Your Bones: Protocol for a Randomized Controlled Trial

OBJECTIVE

The purpose of this trial is to evaluate the effect of twice-weekly, moderate-to-high intensity progressive resistance training (PRT) for 1 year on lumbar spine bone mineral density (BMD) in individuals with low BMD, compared to attention control. Secondary analyses will examine if resistance training improves other health outcomes; if high intensity is more effective than moderate intensity resistance training for all outcomes; the cost of intervention versus benefit; the willingness to pay; and harms.

METHODS

For this study, 324 men or postmenopausal women aged ≥50 years with a femoral neck, total hip, or lumbar spine BMD T-score of ≤-1, or a Fracture Risk Assessment Tool probability of ≥20% for major osteoporotic fracture or ≥ 3% for hip fracture are being recruited to participate in a randomized controlled trial with 1:1:1 randomization. Participants will be stratified by site (3 centers) to twice-weekly, supervised PRT at moderate intensity (about 10 repetitions maximum), to high intensity PRT (≤6 repetitions maximum), or to a home posture and balance exercise program (attention control) for 1 year (resistance training to comparator allocation ratio of 2:1). The primary outcome is lumbar spine BMD via dual-energy X-ray absorptiometry. Secondary outcomes include trabecular bone score, proximal femur and total hip BMD and structure, bone-free and appendicular lean mass, physical functioning, falls, fractures, glucose metabolism, cost per life-year gained, adverse events, and quality of life. Between-group differences will be tested in intention-to-treat and per-protocol analyses using analysis of covariance, chi-square tests, or negative binomial or logistic regression, adjusting for site and baseline values.

IMPACT

The Finding the Optimal Resistance Training Intensity For Your Bones trial will support decision making on resistance training for people at risk of fracture.

Effects of Physical Activity Interventions on Strength, Balance and Falls in Middle-Aged Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Weak lower body strength and balance impairments are fundamental risk factors for mobility impairments and falls that can be improved by physical activity (PA). Previous meta-analyses have focused on these risk factors in adults aged ≥ 65 years. Yet, the potential of PA for improving these risk factors in middle-aged populations has not been systematically investigated. This systematic review and meta-analysis aim to examine the effect of general and structured PA on lower limb strength, postural balance and falls in middle-aged adults.

METHODS

A computerized systematic literature search was conducted in the electronic databases MEDLINE, CINAHL, Web of Science and Cochrane Library. PA intervention types were classified according to the ProFaNE taxonomy. Randomized controlled trials exploring the effects of PA on strength (e.g., leg press one-repetition-maximum), balance (e.g., single limb stance) and falls (e.g., fall rates) in adults aged 40-60 years were systematically searched and included in a network analysis. Moderator analyses were performed for specific subgroups (age, sex, low PA). The methodological quality of the included studies was assessed using the Physiotherapy Evidence Database (PEDro) Scale.

RESULTS

Out of 7170 articles screened, 66 studies (median PEDro score 5) with 3387 participants were included. Strong, significant effects on muscle strength were found for strength (SMD = 1.02), strength-aerobic (SMD = 1.41), strength-endurance (SMD = 0.92) and water-based (SMD = 1.08) training (52 studies, I² = 79.3%). Strength training (SMD = 1.16), strength-aerobic (SMD = 0.98) and 3D training (SMD = 1.31) improved postural balance (30 studies, I² = 88.1%). Moderator analyses revealed significant effects of specific intervention types on certain subgroups and subdomains of strength and balance. No studies were found measuring falls.

CONCLUSIONS

Structured PA interventions in middle-aged adults improve strength and balance outcomes related to functional impairments and falls. Strength training increases both strength and balance and can be recommended to prevent age-related functional decline. However, the interpretability of the results is limited due to considerable heterogeneity and the overall low methodological quality of the included studies. Long-term trials are needed to determine the preventive potential of PA on strength, balance and falls. This meta-analysis may inform guidelines for tailored training during middle age to promote healthy aging. Prospero registration: CRD42020218643.

Effect of Exercise Training on Blood Pressure in Healthy Postmenopausal Females: A Systematic Review with Meta-analysis

INTRODUCTION

The prevalence of hypertension is greater in postmenopausal females compared with males of similar age. Previous meta-analyses of normotensive and hypertensive adults have shown that aerobic exercise training reduces systolic blood pressure (SBP) and/or diastolic blood pressure (DBP). However, the effect of aerobic exercise training on blood pressure specifically within healthy postmenopausal females remains unclear. This systematic review with meta-analysis quantified the effect of aerobic exercise training on resting SBP and DBP in healthy postmenopausal females.

METHODS

The systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines and was registered in PROSPERO (CRD42020198171). The literature search was done in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL Plus, and SPORTDiscus. Randomized controlled trials involving healthy postmenopausal females with normal or high normal blood pressure and undergoing ≥4 wk of aerobic exercise training were included. The total weighted mean change in SBP and DBP was compared between the exercise and the control interventions. A random-effects model was used to calculate the overall effect sizes of the weighted mean differences and the 95% confidence interval (CI).

RESULTS

Twelve studies were included in the meta-analysis (exercise interventions: n = 357, age = 60 ± 4 yr, baseline SBP/DBP = 128 ± 13/79 ± 8 mm Hg; control interventions: n = 330, age = 60 ± 4 yr, baseline SBP/DBP = 126 ± 11/77 ± 6 mm Hg). Compared with the change observed in response to the control interventions, exercise training significantly reduced SBP (-0.43 mm Hg, 95% CI = -0.78 to -0.09, P = 0.02) and DBP (-0.39 mm Hg, 95% CI = -0.73 to -0.05, P = 0.05).

CONCLUSIONS

Aerobic exercise training significantly reduces resting SBP and DBP in healthy postmenopausal females with normal or high normal blood pressure. However, this reduction is small and of uncertain clinical significance.

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.

Health Effects of Soy Isoflavones and Green Tea Catechins on Cancer and Cardiovascular Diseases Based on Urinary Biomarker Levels

Plant polyphenols have various health effects. Genistein, which is abundant in soybeans, and epigallocatechin-3-gallate, which is abundant in green tea, are major flavonoids, a subclass group of polyphenols. Several epidemiological studies have shown that these flavonoids have beneficial effects against cancer and cardiovascular diseases. However, other studies did not show such effects. Several confounding factors, including recall bias, are related to these inconsistent findings, and the determination of metabolites in the urine may be useful in reducing the number of confounding factors. Equipment, which can be used by research participants to collect samples from a portion of voided urine within 24 h without the help of medical workers, has been developed for epidemiological investigations. Previous studies, in which flavonoid metabolites in these urine samples were measured, revealed that soy intake was correlated with a reduced risk of certain types of cancer and cardiovascular diseases worldwide. Although soybeans and green tea consumption may have protective effects against cancer and cardiovascular diseases, further clinical studies that consider different confounding factors are required to provide evidence for the actual impact of dietary flavonoids on human diseases, including cancer and cardiovascular diseases. One possible mechanism involved is discussed in relation to the downregulation of reactive oxygen species and the upregulation of 5'-adenosine monophosphate-activated protein kinase elicited by these flavonoids.

High-Intensity Exercise and Geometric Indices of Hip Bone Strength in Postmenopausal Women on or off Bone Medication: The MEDEX-OP Randomised Controlled Trial

To compare the effects of high-intensity resistance and impact training (HiRIT) to low-intensity, Pilates-based exercise (LiPBE) on proximal femur geometry and explore the influence of antiresorptive medication on those effects. Postmenopausal women with low bone mass, on or off antiresorptive bone medications were randomly allocated, stratified on medication intake, to eight months of twice-weekly, supervised HiRIT (Onero™) or LiPBE (Buff Bones®). 3D hip software was used to analyse proximal femur DXA scans. Outcomes included femoral neck (FN) and total hip (TH), volumetric (e.g. vBMC, vBMD) and geometric (e.g. cortical thickness, cross-sectional area [CSA], section modulus [Z]) indices of bone strength. Data were analysed using analysis of variance. Scans of 102 women were examined: LiPBE, 43; HiRIT, 37; LiPBE-med, 11; HiRIT-med, 11. HiRIT improved TH trabecular vBMC and vBMD (3.1 ± 1.1% versus - 1.2 ± 1.2%, p = 0.008; and 1.5 ± 1.0% versus - 1.6 ± 1.2%, p = 0.042, respectively) and FN and TH total vBMC (2.0 ± 0.8% versus - 0.2 ± 0.7%, p = 0.032; and 0.7 ± 0.4% versus - 0.8 ± 0.6%, p = 0.032, respectively), compared to losses in LiPBE. HiRIT also increased Z while LiPBE did not (p = 0.035). The combination of HiRIT and medication achieved greater improvements in FN total and trabecular vBMD, total BMC, CSA and Z than HiRIT alone. HiRIT improved geometric parameters of proximal femur strength, while LiPBE exercise was largely ineffective. Medication may enhance some HiRIT effects. Findings suggest reduced hip fracture risk in response to HiRIT.Trial registration number ACTRN12617001511325.

The Role of Soy Isoflavones in the Prevention of Bone Loss in Postmenopausal Women: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

The aim of the report was to determine the effects of soy isoflavones on lumbar spine, femoral neck, and total hip bone mineral density (BMD) in menopausal women. MEDLINE (PubMed), EMBASE, and Cochrane Library databases were searched for articles published in English during 1995–2019. Studies were identified and reviewed for inclusion and exclusion eligibility. Weighted mean differences (WMD) were calculated for each study and were pooled by using the random effects model. Eighteen randomized controlled trials were selected for meta-analysis. Different types of soy phytoestrogens, i.e., genistein extracts, soy isoflavones extracts, soy protein isolate, and foods containing diverse amounts of isoflavones were used in the studies. The analysis showed that daily intake of 106 (range, 40–300) mg of isoflavones for 6–24 months moderately but statistically significantly positively affects BMD, compared with controls: lumbar spine WMD = 1.63 (95% CI: 0.51 to 2.75)%, p = 0004; femoral neck WMD = 1.87 (95% CI: 0.14 to 3.60)%, p = 0.034; and total hip WMD = 0.39 (95% CI: 0.08 to 0.69)%, p = 0.013. Subgroups analyses indicated that the varying effects of isoflavones on BMD across the trials might be associated with intervention duration, racial diversity (Caucasian, Asian), time after menopause, form of supplements (especially genistein), and dose of isoflavones. Our review and meta-analysis suggest that soy isoflavones are effective in slowing down bone loss after menopause.

Role of Phytoestrogen-Rich Bioactive Substances (Linum usitatissimum L., Glycine max L., Trifolium pratense L.) in Cardiovascular Disease Prevention in Postmenopausal Women: A Systematic Review and Meta-Analysis

The aim of this report was to determine the impact of flaxseed, soy and red clover, and their bioactive substances on the lipid profile in postmenopausal women in cardiovascular diseases prevention. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Meta-analysis indicates that the intake of flaxseed by postmenopausal women is associated with a statistically significant reduction in total cholesterol (TC) levels (weighted-mean difference (WMD) = -0.26; 95% confidence interval (95% CI): -0.38 to -0.13; p = 0.0001), low-density lipoprotein cholesterol (LDL-C) levels (WMD = -0.19; 95% CI: -0.30 to -0.08; p = 0.0006), and high-density lipoprotein cholesterol (HDL-C) levels (WMD = -0.06; 95% CI: -0.11 to -0.01; p = 0.0150). The effect of soy protein on the lipid profile showed a significant decrease in TC levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0048, LDL-C levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0067, as well as a significant increase in HDL-C levels: WMD = 0.05; 95% CI: 0.02-0.08; p = 0.0034. Changes in the lipid profile showed a significant reduction in TC levels after the use of red clover (WMD = -0.11; 95% CI: -0.18--0.04; p = 0.0017) and a significant increase in HDL-C levels (WMD = 0.04; 95% CI: 0.01 to 0.07; p = 0.0165). This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.

Effect of isoflavone supplementation on menopausal symptoms: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND/OBJECTIVES

Complementary and alternative medicines can be used to alleviate climacteric symptoms that significantly affect the quality of life of postmenopausal women. Isoflavones are the most common plant-based therapies for postmenopausal changes, but the results of previous studies have been controversial.

MATERIALS/METHODS

To investigate whether isoflavones would affect menopausal symptoms as well as ovarian hormones, we performed a systematic review and meta-analysis. The PubMed and EMBASE databases were used to perform the systematic search. Included studies were limited to randomized controlled trials (RCTs) assessing the impact of isoflavone supplementation on menopausal symptoms.

RESULTS

Eleven studies were included for the final quantitative assessment. Isoflavone intervention was varied between 49.3 and 135 mg of isoflavones per day for 12 wk–2 yrs. The meta-analysis showed that supplementation of isoflavones significantly increased the estradiol levels (standardized mean difference [SMD] = 0.615, P = 0.035) and Kupperman index (SMD = 3.121, P = 0.003) but had no significant effect on hot flashes, follicle-stimulating hormone, and luteinizing hormone. However, both estradiol and the Kupperman index showed significant heterogeneity among studies (I² = 94.7%, P < 0.001 and I² = 98.1%, P < 0.001, respectively).

CONCLUSIONS

Although the results showed a significant SMD in estradiol and the Kupperman index, the results should be interpreted with caution due to the high heterogeneity. Further validation with a larger RCT will be necessary. Overall, isoflavone supplementation has distinct effects on the climacteric symptoms and hormonal changes in postmenopausal women.

Effects of Soy Protein Containing of Isoflavones and Isoflavones Extract on Plasma Lipid Profile in Postmenopausal Women as a Potential Prevention Factor in Cardiovascular Diseases: Systematic Review and Meta-Analysis of Randomized Controlled Trials

The aim of the report was to evaluate the impact of soy protein containing isoflavones and soy isoflavones extract on lipid profile in postmenopausal women, as compared with placebo or protein of milk, casein or isolated soy protein with or without trace isoflavone content. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Quantitative data synthesis was performed by applying a random-effects model. Subgroup analysis and meta-regression were performed to assess the modifiers of treatment response. In total, in the analysis studies, 2305 postmenopausal women took part. Changes in the lipid profile showed statistically significant decreases of total cholesterol by −0.12 (95% CI: −0.21, −0.03) mmol/L, −4.64 (95% CI: −8.12, −1.16) mg/dL, p = 0.01 and increased HDL-cholesterol by 0.03 (95% CI: 0.00, 0.06) mmol/L, 1.15 (95% CI: 0.00, 1.93) mg/dL, p = 0.05, as well as in LDL-cholesterol −0.05 (95% CI: −0.11, 0.01) mmol/L, −1.93 (95% CI: −4.25, 0.39) mg/dL, p = 0.08 and triacylglycerols −0.07 (95% CI: −0.14, 0.00) mmol/L, −6.123 (95% CI: −12.25, 0.00) mg/dL, p = 0.06. Our results suggests that soy and its isoflavones can be effective in correction changes in lipid metabolism in postmenopausal women and may favorably influence in preventing cardiovascular events.

Current Perspectives on the Beneficial Effects of Soybean Isoflavones and Their Metabolites for Humans

Soybeans are rich in proteins and lipids and have become a staple part of the human diet. Besides their nutritional excellence, they have also been shown to contain various functional components, including isoflavones, and have consequently received increasing attention as a functional food item. Isoflavones are structurally similar to 17-β-estradiol and bind to estrogen receptors (ERα and ERβ). The estrogenic activity of isoflavones ranges from a hundredth to a thousandth of that of estrogen itself. Isoflavones play a role in regulating the effects of estrogen in the human body, depending on the situation. Thus, when estrogen is insufficient, isoflavones perform the functions of estrogen, and when estrogen is excessive, isoflavones block the estrogen receptors to which estrogen binds, thus acting as an estrogen antagonist. In particular, estrogen antagonistic activity is important in the breast, endometrium, and prostate, and such antagonistic activity suppresses cancer occurrence. Genistein, an isoflavone, has cancer-suppressing effects on estrogen receptor-positive (ER+) cancers, including breast cancer. It suppresses the function of enzymes such as tyrosine protein kinase, mitogen-activated kinase, and DNA polymerase II, thus inhibiting cell proliferation and inducing apoptosis. Genistein is the most biologically active and potent isoflavone candidate for cancer prevention. Furthermore, among the various physiological functions of isoflavones, they are best known for their antioxidant activities. S-Equol, a metabolite of genistein and daidzein, has strong antioxidative effects; however, the ability to metabolize daidzein into S-equol varies based on racial and individual differences. The antioxidant activity of isoflavones may be effective in preventing dementia by inhibiting the phosphorylation of Alzheimer's-related tau proteins. Genistein also reduces allergic responses by limiting the expression of mast cell IgE receptors, which are involved in allergic responses. In addition, they have been known to prevent and treat various diseases, including cardiovascular diseases, metabolic syndromes, osteoporosis, diabetes, brain-related diseases, high blood pressure, hyperlipidemia, obesity, and inflammation. Further, it also has positive effects on menstrual irregularity in non-menopausal women and relieving menopausal symptoms in middle-aged women. Recently, soybean consumption has shown steep increasing trend in Western countries where the intake was previously only 1/20-1/50 of that in Asian countries. In this review, I have dealt with the latest research trends that have shown substantial interest in the biological efficacy of isoflavones in humans and plants, and their related mechanisms.

Mental Health Benefits of Exercise and Genistein in Elderly Rats

Elderly is a part of life that is associated with physical and mental disorders. The present study aimed to investigate the effect of 8 weeks of high-intensity interval training (HIIT) along with genistein (Ge) on memory, anxiety, physical persistence and aerobic power in elderly rats. Forty elderly rats were randomly assigned to five groups of eight rats including 1) control (C), 2) sham (Sh), 3) HIIT, 4) HIIT+Ge, and 5)Ge. During 8-week groups 3 and 4 performed HIIT for three sessions per week and groups 4 and 5 received 60 mg/kg/day Ge peritoneally. Physical persistence (by forced swimming test), memory (by shuttle box and Y maze tests), anxiety (by elevated plus-maze test) and aerobic power (by exhaustive running on treadmill) were measured. HIIT, Ge, and HIIT+Ge significantly increased physical persistence and memory (P ≤0.05), HIIT and HIIT+Ge significantly decrease anxiety and increased aerobic power (P ≤0.05) and HIIT+Ge had higher effect on the decrease of anxiety and increase of memory compared to HIIT and Ge (P≤0.05). Although HIIT and Ge alone can enhance physical persistence, memory and anxiety in elderly rats nevertheless it seems that HIIT simultaneously with Ge has more favorable mental health benefits compared to HIIT and Ge alone.

The effect of exercise intensity on bone in postmenopausal women (part 2): A meta-analysis

BACKGROUND

Previous reviews have concluded that exercise has only modest effects on bone mineral density (BMD) in postmenopausal women. Despite the well-recognized strong positive relationship between load magnitude and bone response observed from animal research, the majority of human trials have examined the effects of only low to moderate intensity exercise on bone. We speculated that meta-analysing according to intensity may reveal a more potent exercise effect at higher intensity.

OBJECTIVES

To determine the effects of low, moderate and high intensity exercise on BMD at the spine and hip in postmenopausal women.

METHODS

Electronic databases and reference lists were searched for RCTs that examined the effect of exercise compared to control on DXA-derived lumbar spine, femoral neck or total hip BMD in healthy postmenopausal women. Interventions were classified as low, moderate or high intensity and pooled based on classification. Mean differences (MD) were calculated using random effects models and a risk of bias analysis was undertaken. To determine the effect of different exercise types (resistance and impact training) on BMD outcomes, subgroup analyses for all intensity categories and outcomes were conducted. Separate meta-analyses were undertaken to examine the influence of adding exercise to a bone medication intervention and to examine exercise effects on fracture risk.

RESULTS

Fifty-three trials, testing 63 interventions (19 low, 40 moderate, 4 high intensity) were included. At the lumbar spine, high intensity exercise yielded greater BMD effects (MD = 0.031 g/cm² 95% CI [0.012, 0.049], p = 0.002) than moderate (MD = 0.012 g/cm² 95% CI [0.008, 0.017], p < 0.001) and low intensity (MD = 0.010 g/cm² 95% CI [0.005, 0.015], p < 0.001). Low and moderate intensity exercise was equally effective at the femoral neck (low: 0.011 g/cm² 95% CI [0.006, 0.016], p < 0.001; moderate: 0.011 g/cm² 95% CI [0.007, 0.015], p < 0.001), but no effect of high-intensity exercise was observed. Moderate intensity exercise increased total hip BMD (0.008 g/cm² 95% CI [0.004, 0.012], p < 0.001), but low intensity did not. There were insufficient data to meta-analyse the effect of high intensity exercise at the total hip. Resistance training, potentially in combination with impact training, appears to be the most effective osteogenic stimulus at the spine and hip. Findings from meta-regression analyses were not informative and no influence of exercise on medication efficacy was observed. Risk of bias was mainly low or unclear due to insufficient information reported.

CONCLUSION

High intensity exercise is a more effective stimulus for lumbar spine BMD than low or moderate intensity, but not femoral neck BMD, however, the latter finding may be due to lack of power. While data from high-intensity exercise interventions are limited, the current comprehensive meta-analysis demonstrates the same positive relationship between load magnitude and bone response in humans that is observed in animal research. Findings have implications for optimal exercise prescription for osteoporosis in postmenopausal women.

STUDY REGISTRATION

Registered on PROSPERO (CRD42018117254).

The effect of exercise intensity on bone in postmenopausal women (part 1): A systematic review

BACKGROUND

Previous systematic reviews and meta-analyses of exercise effects on bone have reported null or modest effect sizes. While animal research has determined that a strong positive relationship exists between load magnitude/intensity and bone adaptation, nevertheless many human exercise interventions have been applied at low intensity. Meta-analytic pooling of exercise interventions irrespective of intensity dilutes the ability to detect efficacy of any one training regimen. Parsing out efficacy of low, moderate and high intensity exercise interventions will assist the determination of optimal exercise prescription for bone.

OBJECTIVES

First, to summarise and critically evaluate existing evidence of exercise effect on bone mass, bone structure and bone turnover markers (BTMs) in healthy postmenopausal women. Second, to examine the influence of intensity on bone response to exercise.

METHODS

Electronic databases (Embase, Scopus, CINAHL Plus, SPORTDiscus), database platforms (PubMed, Cochrane CENTRAL, ProQuest Central, Web of Science) and reference lists of included studies were searched for controlled trials and randomised controlled trials that described the effect of any exercise intervention compared to control on bone mass, bone structure or BTMs in healthy postmenopausal women. Fracture incidence was included as an exploratory endpoint. Data was extracted and weighed against the results of a comprehensive risk of bias analysis.

RESULTS

One hundred trials were included, investigating a total of 120 exercise interventions. Of those, 57 interventions were low intensity, 57 were moderate, and six were high intensity. On balance, low intensity exercise was not an effective stimulus to increase bone mass. Higher quality evidence suggests moderate to high intensity interventions, particularly those that combined high intensity resistance and impact training, were most beneficial for bone mass. Only high intensity exercise appears to improve structural parameters of bone strength, however, data are limited. Only low and moderate intensity interventions have measured BTMs and no notable benefits have been observed. The quality of trials varied greatly, and risk of bias determinations were frequently limited by insufficiently reported detail.

CONCLUSION

Heterogeneity in both study quality and outcomes limits the ability to draw strong conclusions from this comprehensive systematic review of RCT and CT reports. Nevertheless, there is a tendency in the higher quality data to indicate exercise intensity is positively related to the adaptive bone response. Part 2 of this review series reports a meta-analysis of the RCT data in order to draw quantitative conclusions from the higher quality trials.

STUDY REGISTRATION

Registered on PROSPERO (CRD42018117254).

Effect of 12 months of creatine supplementation and whole-body resistance training on measures of bone, muscle and strength in older males

BACKGROUND

The combination of creatine supplementation and resistance training (10-12 weeks) has been shown to increase bone mineral content and reduce a urinary indicator of bone resorption in older males compared with placebo. However, the longer-term effects (12 months) of creatine and resistance training on bone mineral density and bone geometric properties in older males is unknown.

AIM

To assess the effects of 12 months of creatine supplementation and supervised, whole-body resistance training on bone mineral density, bone geometric properties, muscle accretion, and strength in older males.

METHODS

Participants were randomized to supplement with creatine (n = 18, 49-69 years, 0.1 g·kg^-1·d^-1) or placebo (n = 20, 49-67 years, 0.1 g·kg^-1·d^-1) during 12 months of supervised, whole-body resistance training.

RESULTS

After 12 months of training, both groups experienced similar changes in bone mineral density and geometry, bone speed of sound, lean tissue and fat mass, muscle thickness, and muscle strength. There was a trend (p = 0.061) for creatine to increase the section modulus of the narrow part of the femoral neck, an indicator of bone bending strength, compared with placebo. Adverse events did not differ between creatine and placebo.

CONCLUSIONS

Twelve months of creatine supplementation and supervised, whole-body resistance training had no greater effect on measures of bone, muscle, or strength in older males compared with placebo.

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.

Isoflavone combined with exercise on bone mineral density in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

This meta-analysis of randomized control trials (RCTs) aimed to evaluate the effects of isoflavones supplementation combined with exercise training on bone mineral density (BMD) in postmenopausal women.

METHODS

Two reviewers did a complete search of two electronic database (Medline, PubMed) records up to January 31, 2019. Risk of bias was classified based on the Cochrane Collaboration tool. The pooled standard mean difference (SMD) combined with 95% confidence interval (CI) was used as the effect size of BMD values.

RESULTS

A total of four RCTs with 609 participants were included for meta-analysis. The BMD did not differ significantly between isoflavone supplementation combined with exercise training group and placebo group (sub-whole body: SMD = 0.00, 95% CI, -0.23 to 0.24; lumbar spine: SMD = 0.15, 95% CI, -0.30 to 0.60; total hip: SMD = 0.05, 95% CI, -0.18 to 0.298; femoral neck: SMD = 0.10, 95% CI, -0.23 to 0.43; trochanter: SMD = 0.09, 95% CI, -0.14 to 0.33; ward's triangle: SMD = -0.03, 95% CI, -0.24 to 0.30). In addition, combined intervention did not provide additive effects on BMD improvements compared with exercise or isoflavone supplementation alone. The trials included in this meta-analysis were small and some had methodological limitations.

CONCLUSION

The present meta-analysis reveals that isoflavone supplements combined with exercise training do not significantly increase BMD in postmenopausal women. In addition, combined intervention does not provide additive effects on BMD improvements compared with exercise or isoflavone supplementation alone.

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.

Effect of a pulse-based diet and aerobic exercise on bone measures and body composition in women with polycystic ovary syndrome: A randomized controlled trial

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, with clinical symptoms including menstrual dysfunction and hyperandrogenemia, as well as insulin resistance which is thought to be a key contributing factor to symptoms. Insulin is also thought to positively affect bone while oligo- and amenorrhea are known to negatively affect bone. Lifestyle modification is the first recommendation to treat symptoms of PCOS; however, little is known about the effect of lifestyle interventions on bone measures in this population. Pulses (e.g., chickpeas, beans, split peas, lentils) have been shown to lower fasting insulin, and the objective of this study was to determine the effect of a pulse-based diet compared to the therapeutic lifestyle changes (TLC) diet on bone measures and body composition in women with PCOS. Women aged 18-35 years with PCOS were randomized to either a pulse-based diet or the TLC diet for 16-weeks while following an aerobic exercise program. Thirty-one in the TLC group and 29 in the pulse group completed dual-energy X-ray absorptiometry analysis following the intervention. After 16-weeks, both groups had a lower BMI, whole body fat mass, and % fat (p < 0.005), with no difference in lean mass. In both groups, lumbar spine bone mineral content (BMC) and density were higher following the intervention (p < 0.05) while femoral neck bone mineral density (BMD) was lower (p < 0.05). Intertrochanteric section modulus improved in both groups while there was a group x time interaction in femoral shaft subperiosteal width which was more favorable in the pulse group (p < 0.05). This study demonstrates that the femoral neck may be compromised during a lifestyle intervention in women with PCOS. Research is warranted to preserve bone health during lifestyle change in women with PCOS.

Physical activity and skeletal health in adults

The purpose of this Review is to examine the associations between physical activity and skeletal health, with an emphasis on observational studies with fracture outcomes and randomised controlled trials (RCTs) of physical activity interventions in adults older than 40 years. In general, increased physical activity-primarily leisure time activity or moderate or vigorous physical activity-is associated with a 1-40% lower risk of hip and all fractures. The primary limitation of these studies relates to health status; healthy people are more likely to exercise and less likely to fracture. Although there is no sufficiently powered RCT of exercise with a fracture outcome, there is evidence that some types of exercise prevent falls and bone loss, and meta-analyses support the anti-fracture effectiveness of exercise. RCTs and meta-analyses suggest that programmes combining impact exercise with moderate or high-intensity progressive resistance exercise might maintain or improve bone mass and prevent fractures, and that functional strength and balance training prevents falls.

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.

Effects of high-velocity resistance training and creatine supplementation in untrained healthy aging males

The purpose was to investigate the effects of high-velocity resistance training (HVRT) and creatine supplementation in untrained healthy aging males. Participants were randomized to supplement with creatine (0.1 g·kg−1·day−1 of creatine + 0.1 g·kg−1·day−1 of maltodextrin) or placebo (0.2 g·kg−1·day−1 of maltodextrin) during 8 weeks of HVRT. Prior to and following HVRT and supplementation, assessments were made for muscle strength, muscle thickness, peak torque, and physical performance. There was a significant increase over time for all measures of muscle strength (p < 0.001), muscle thickness (p < 0.001), and some measures of peak torque (knee flexion; 1.05 and 3.14 rad/s; p < 0.001) and physical performance (balance board time-to-completion; p = 0.017). There was a group × time interaction for leg press strength (p = 0.044) and total lower-body strength (leg press, knee flexion, knee extension combined; p = 0.039). The creatine group experienced greater gains in leg press and total lower-body strength compared with the placebo group, with no other differences. HVRT increases muscle strength, muscle thickness, and some measures of peak torque and physical performance in untrained healthy aging males. The addition of creatine supplementation to HVRT further augments the gains in leg press and total lower-body strength.

Novelty High-velocity resistance training increases muscle mass and performance. Creatine supplementation increases lower-body muscle strength. High-velocity resistance training and creatine supplementation are safe interventions for aging adults.

The Effect of a Low Glycemic Index Pulse-Based Diet on Insulin Sensitivity, Insulin Resistance, Bone Resorption and Cardiovascular Risk Factors during Bed Rest

We determined the effects of a low glycemic-index pulse-based diet (i.e., containing lentils, chick peas, beans, and split peas) compared to a typical hospital diet on insulin sensitivity assessed by the Matsuda index from the insulin and glucose response to a two-hour oral glucose tolerance test, insulin resistance assessed by the homeostatic model assessment of insulin resistance (HOMA-IR), bone resorption assessed by 24 h excretion of urinary n-telopeptides(Ntx) and cardiovascular risk factors (blood lipids, blood pressure, arterial stiffness and heart rate variability) during bed rest. Using a randomized, counter-balanced cross-over design with one-month washout, six healthy individuals (30 ± 12 years) consumed the diets during four days of bed rest. The Matsuda index, HOMA-IR, urinary Ntx and cardiovascular risk factors were determined at baseline and after the last day of bed rest. Compared to the typical hospital diet, the pulse-based diet improved the Matsuda index (indicating increased insulin sensitivity; baseline to post-bed rest: 6.54 ± 1.94 to 6.39 ± 2.71 hospital diet vs. 7.14 ± 2.36 to 8.75 ± 3.13 pulse-based diet; p = 0.017), decreased HOMA-IR (1.38 ± 0.54 to 1.37 ± 0.50 hospital diet vs. 1.48 ± 0.54 to 0.88 ± 0.37 pulse-based diet; p = 0.022), and attenuated the increase in Ntx (+89 ± 75% hospital diet vs. +33 ± 20% pulse-based diet; p = 0.035). No differences for changes in cardiovascular risk factors were found between the two diet conditions, with the exception of decreased diastolic blood pressure during day three of bed rest in the pulse-based versus hospital diet (61 ± 9 vs. 66 ± 7 mmHg; p = 0.03). A pulse-based diet was superior to a hospital diet for maintaining insulin sensitivity, preventing insulin resistance, attenuating bone resorption and decreasing diastolic blood pressure during four days of bed rest.

Soy isoflavones prevent bone resorption and loss, a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Osteoporosis is a common bone disease characterized by reduced bone mass resulting from continuous bone resorption.

METHODS

PubMed, Scopus, and Embase were searched to find published trials on the effect of soy isoflavones on bone mineral density (BMD) and bone turnover markers (bone-specific alkaline phosphatase, osteocalcin, osteoprotegerin, pyridinoline, deoxypyridinoline, C-telopeptide, and N-telopeptide). Random-effects inverse-variance model was used to calculate the pooled effects.

RESULTS

A total of 5313 articles were found, screened, and assessed for eligibility, and finally 52 trials were included in the meta-analysis. Consumption of soy isoflavones caused significant improvement in BMD of lumbar spine (mean difference (MD) = 0.76%; 95% CI: 0.09, 1.42%; p = 0.03), hip (MD = 0.22%; 95% CI: 0.02, 0.42%; p = 0.04), and femoral neck (MD = 2.27%; 95% CI: 1.22, 3.31%; p < 0.001). Subgroup analysis showed that in all 3 sites, the improvement was significant in normal weight subjects and interventions longer than a year, although trial location and dosage were also factors influencing isoflavones' impact on BMD. Among markers of bone turnover, osteoprotegerin (MD = 5.79; 95% CI: 3.08, 8.51 pg/ml; p < 0.001), pyridinoline (MD = -5.13; 95% CI: -7.76, -2.50 nmol/mmol; p < 0.001), and C-telopeptides (MD = -0.08; 95% CI: -0.16, -0.00 ng/ml; p = 0.04) were favorably affected by isoflavones while osteocalcin and bone alkaline phosphatase did not change. Subgroup analysis of bone markers showed that in overweight/obese individuals and dosages <90 mg/day, isoflavones are more effective.

CONCLUSIONS

Soy isoflavones prevent osteoporosis-related bone loss in any weight status or treatment duration. They increase BMD in normal weight subjects and diminish bone resorption in overweight/obese individuals. Although bone resorption may be decelerated over short-term isoflavone consumption, periods longer than a year are probably needed to affect BMD. Isoflavones also appear benefits on bone in any dose or subjects' ethnicity.

Effect of Creatine Supplementation Dosing Strategies on Aging Muscle Performance

OBJECTIVE

This study compared the effects of different creatine supplementation dosages, independent of resistance training, on aging muscle performance and functionality.

DESIGN AND PARTICIPANTS

Using a double-blind, repeated measures design, participants were randomized to one of three groups: Creatine-High (CR-H; n=11; 0.3 g/kg/day of creatine + 0.1 g/kg/day of maltodextrin), Creatine-Moderate (CR-M: n=11; 0.1 g/kg/day of creatine + 0.3 g/kg/day of maltodextrin) or Placebo (PLA; n=11; 0.4 g/kg/day of maltodextrin) for 10 consecutive days.

MEASUREMENTS

The primary dependent variables measured at baseline and after supplementation included muscle strength (1-repetition maximum leg press, chest press, hand-grip), muscle endurance (leg press and chest press; maximal number of repetitions performed for 1 set at 80% and 70% baseline 1-repetition maximum respectively), and physical performance (dynamic balance).

RESULTS

There was a significant increase over time for muscle strength (Leg press: CR-H pre 161.5 ± 55.1 kg, post 169.2 ± 59.2 kg; CR-M pre 145.2 ± 47.7 kg, post 151.7 ± 45.0 kg; PLA pre 163.7 ± 51.5 kg, post 178.2 ± 65.6 kg, p = 0.001; Chest press: CR-H pre 57.0 ± 26.2 kg, post 58.8 ± 28.0 kg; CR-M pre 54.5 ± 27.9 kg, post 56.8 ± 30.1 kg; PLA pre 55.1 ± 26.9 kg, post 58.5 ± 30.1 kg, p = 0.001) and endurance (Leg press: CR-H pre 17.1 ± 6.0 reps, post 21.0 ± 7.2 reps; CR-M pre 24.1 ± 11.6 reps, post 29.1 ± 17.0 reps; PLA pre 23.8 ± 9.7 reps, post 29.5 ± 11.9 reps, p = 0. 001; Chest press: CR-H pre 15.6 ± 2.7 reps, post 18.9 ± 2.7 reps; CR-M pre 18.0 ± 5.0 reps, post 19.9 ± 7.1 reps; PLA pre 20.5 ± 6.2 reps, post 21.6 ± 5.5 reps, p = 0. 001), with no other differences.

CONCLUSION

Short-term creatine supplementation, independent of dosage and resistance training, has no effect on aging muscle performance.

Adverse events and safety issues associated with physical activity and exercise for adults with osteoporosis and osteopenia: A systematic review of observational studies and an updated review of interventional studies

OBJECTIVES

We conducted a systematic review to identify adverse effects of physical activity and/or exercise for adults with osteoporosis/osteopenia. We synthesised evidence from observational studies, and updated three previously published systematic reviews.

METHODS

We searched MEDLINE, EMBASE, CINAHL, Web of Science, grey literature and reference lists of relevant studies. Selection criteria were: (1) observational studies in patients with osteoporosis/osteopenia; and (2) in accordance with the criteria used in the previous reviews. A narrative synthesis was conducted for the observational data. Random effects meta-analysis was undertaken for the review updates.

RESULTS

For the observational synthesis 14 studies were included. The majority of studies reported no adverse events, reduced incidence/improvement, or no significant change after physical activity or exercise. Activities that involved spinal flexion (certain yoga moves and sit-ups) were associated with a greater risk of vertebral fractures but these events were rare. For the update of reviews, 57 additional studies were identified. Exercise was generally associated with a greater number of minor adverse events including mild muscle/joint pain. Serious adverse events were rare and could not be attributed to the intervention.

CONCLUSION

Patients with osteoporosis/osteopenia can safely participate in structured exercise programmes, whether at home or in supervised facilities. Systematic review registration for observational studies: PROSPERO 2017: CRD42017070551.

Isoflavone supplementation plus combined aerobic and resistance exercise do not change phase angle values in postmenopausal women: A randomized placebo-controlled clinical trial

OBJECTIVE

The aim of this study was to evaluate the effect of isoflavone supplementation plus combined exercise protocol on phase angle (PhA) values in postmenopausal women.

METHODS

Thirty postmenopausal women were randomly assigned in a double blind, placebo-controlled clinical trial divided into two groups: 100 mg/day of isoflavone supplementation (n = 16) and 100 mg/day of starch (placebo; n = 14). In addition, both groups performed a combined aerobic and resistance exercise during 10 weeks. Body composition and PhA were evaluated by bioelectrical impedance.

RESULTS

PhA values did not change in the isoflavone group (PRE: 6.7 ± 0.7° to POST: 6.7 ± 0.6°) and in the placebo group (PRE: 7.2 ± 1.0° to POST: 6.8 ± 0.5°); p group = 0.304, p time = 0.227, p group x time interaction = 0.137. Additionally, delta values were not different (0.04 ± 0.5° vs. -0.40 ± 0.99°; p = 0.176) between isoflavone and placebo groups, respectively.

CONCLUSION

We conclude that isoflavone supplementation plus combined aerobic and resistance exercise did not change PhA in postmenopausal women. The patients were part of ClinicalTrials.gov: NCT03008785.

A systematic review of the exercise effect on bone health: the importance of assessing mechanical loading in perimenopausal and postmenopausal women

OBJECTIVE

The aims of this systematic review were to determine the general effects of exercise on areal bone mineral density (BMD) in perimenopausal and postmenopausal women, and to provide information on the most suitable bone-loading exercise regimens that may improve bone health in this population group.

METHODS

A computerized, systematic literature search was performed in the electronic databases PubMed, Web of Science, CINAHL, SPORTDiscus, and The Cochrane Library, from January 2005 to November 2015, to identify all randomized controlled trials related to exercise in perimenopausal and postmenopausal women. The initial search identified 915 studies, with a final yield of 10 studies. Only randomized controlled trials that examined the effects of exercise programs longer than 24 weeks in women aged 35 to 70 years were included. The 10 studies quantified at least BMD and described training variables adequately (training period, frequency, volume, intensity).

RESULTS

Ten studies with moderate quality evidence (6.4 ± 1.8 points, range 4-9) were included. Significant changes in lumbar and femoral neck BMD were found mainly with high-impact exercise and whole body vibration interventions.

CONCLUSIONS

While training effects must be interpreted with caution because of the heterogeneity of the protocols and exercises performed, this systematic review confirmed the effectiveness of impact exercises combined with other forms of training (vibration or strength training) to preserve BMD in perimenopausal and postmenopausal women. Despite the results possibly not representing a general dose-response relationship, we highlight the importance of quantifying loading intensity and frequency by means of accelerometry as these parameters are determinants for bone adaptation.

The Effects of Isoflavone Supplementation Plus Combined Exercise on Lipid Levels, and Inflammatory and Oxidative Stress Markers in Postmenopausal Women

This study tested the effect of isoflavone supplementation in addition to combined exercise training on plasma lipid levels, inflammatory markers and oxidative stress in postmenopausal women. Thirty-two healthy and non-obese postmenopausal women without hormone therapy were randomly assigned to exercise + placebo (PLA; n = 15) or exercise + isoflavone supplementation (ISO; n = 17) groups. They performed 30 sessions of combined exercises (aerobic plus resistance) over ten weeks and consumed 100 mg of isoflavone supplementation or placebo. Blood samples were collected after an overnight fast to analyze the lipid profile, interleukin-6 (IL-6), interleukin-8 (IL-8), superoxide dismutase (SOD), total antioxidant capacity (FRAP), and thiobarbituric acid reactive substances (TBARS), before and after ten weeks of the intervention. There were no differences in the changes (pre vs. post) between groups for any of the inflammatory markers, oxidative stress markers or lipid profile variables. However, interleukin-8 was different between pre- and post-tests (p < 0.001) in both groups (&Delta; = 7.61 and 5.61 pg/mL) as were cholesterol levels (p < 0.05), with no interaction between groups. The combination of isoflavone supplementation and exercise training did not alter oxidative stress markers in postmenopausal women, but exercise training alone may increase IL-8 and decrease total cholesterol levels.

Impact of Pilates Exercise in Multiple Sclerosis: A Randomized Controlled Trial

Background

Pilates is a series of exercises based on whole-body movement and may improve mobility in people with multiple sclerosis (MS). The purpose of this study was to determine the effect of Pilates on walking performance in people with MS.

Methods

30 individuals with MS who were not restricted to a wheelchair or scooter (Patient-Determined Disease Steps scale score <7) were randomized to receive Pilates (twice weekly) and massage therapy (once weekly) or once-weekly massage therapy only (control group). The Pilates was delivered in a group setting (five to ten participants per session). The primary outcome was change in walking performance (6-Minute Walk Test) after 12 weeks. Secondary outcomes included functional ability (Timed Up and Go test), balance (Fullerton Advanced Balance Scale), flexibility (sit and reach test), body composition (dual-energy X-ray absorptiometry), core endurance (plank-hold test), and muscle strength and voluntary activation (quadriceps). Intention-to-treat analysis was performed using a two-factor repeated-measures analysis of variance.

Results

Walking distance increased by a mean (SD) of 52.4 (40.2) m in the Pilates group versus 15.0 (34.1) m in the control group (group × time, P = .01). Mean (SD) time to complete the Timed Up and Go test decreased by 1.5 (2.8) seconds in the Pilates group versus an increase of 0.3 (0.9) seconds in the control group (group × time, P = .03). There were no other significant differences between groups over time.

Conclusions

Pilates improved walking performance and functional ability in persons with MS and is a viable exercise option to help manage the disease.

Women With Polycystic Ovary Syndrome Have Comparable Hip Bone Geometry to Age-Matched Control Women

Polycystic ovary syndrome (PCOS) is an endocrine disorder affecting women of reproductive age manifesting with polycystic ovaries, menstrual irregularities, hyperandrogenism, hirsutism, and insulin resistance. The oligomenorrhea and amenorrhea characteristic to PCOS are associated with low bone mineral density (BMD); conversely, the hyperandrogenism and hyperinsulinemia may elicit a protective effect on BMD. As bone geometric properties provide additional information about bone strength, the objective of this study was to compare measures of hip geometry in women with PCOS to a healthy female population. Using dual-energy X-ray absorptiometry, BMD and measures of hip geometry were determined in women with PCOS (n = 60) and healthy controls (n = 60) aged 18-35 years. Clinical biochemical measures were also determined in women with PCOS. Measures of hip geometry, including cross-sectional area, cross-sectional moment of inertia, subperiosteal width (SPW), and section modulus, were similar between groups following correction for body mass index (BMI) (all p > 0.05) with intertrochanter SPW significantly lower in women with PCOS (p < 0.05). BMI-corrected whole body BMD as well as the lumbar spine and regions of proximal femur were also comparable between groups. In women with PCOS, BMI-corrected correlations were found between insulin and femoral shaft SPW (r = 0.322, p < 0.05), glucose and femoral neck (r = 0.301, p < 0.05), and trochanter BMD (0.348, p < 0.05), as well as between testosterone and femoral neck BMD (0.376, p < 0.05) and narrow neck cross-sectional area (0.306, p < 0.05). This study demonstrates that women with PCOS may have compromised intertrochanter SPW while oligomenorrhea appears to have no detrimental effect on bone density or geometry in women with PCOS.

A systematic review and meta-analysis of the effects of isoflavone formulations against estrogen-deficient bone resorption in peri- and postmenopausal women

Background: Age-related estrogen deficiency leads to accelerated bone resorption. There is evidence that, through selective estrogen receptor modulation, isoflavones may exert beneficial effects against estrogen-deficient bone loss. Isoflavone aglycones show higher bioavailability than their glycosidic counterparts and thus may have greater potency.Objective: To summarize evidence, we executed a systematic review and meta-analysis examining isoflavone therapies and bone mineral density (BMD) loss in peri- and postmenopausal women.Design: We systematically searched EMBASE and PubMed for randomized controlled trials (RCTs) evaluating isoflavone therapies for treating BMD loss at the lumbar spine and femoral neck in estrogen-deficient women. Separate meta-analyses were carried out with the use of random-effects models for the lumbar spine and femoral neck for all studies providing isoflavones as aglycones.Results: Twenty-six RCTs (n = 2652) were included in the meta-analysis. At the lumbar spine, isoflavone treatment was associated with a significantly (P < 0.00001) higher weighted mean difference (WMD) of BMD change of 0.01 (95% CI: 0.01, 0.02) than the control. For the femoral neck (18 RCTs, n = 1604), isoflavone treatment showed a significantly (P < 0.01) higher WMD of BMD change of 0.01 (95% CI: 0.00, 0.02) compared with the control. When isolating studies that provide isoflavone aglycones in their treatment arm, the average effect was further significantly increased at the spine (5 RCTs, n = 682) to 0.04 (P < 0.00001; 95% CI: 0.02, 0.05) and femoral neck (4 RCTs, n = 524) to 0.03 (P < 0.05; 95% CI: 0.00, 0.06) compared with the control. This protective effect against bone loss disappeared when only studies with formulations comprising predominantly isoflavone glycosides were included.Conclusions: Isoflavone treatments exert a moderately beneficial effect against estrogen-deficient bone loss in women. The effect appears dependent on whether isoflavone treatments are in aglycone form; we conclude that beneficial effects against bone loss may be enhanced for isoflavone aglycones.

Long-term exercise training and soy isoflavones to improve quality of life and climacteric symptoms

OBJECTIVE

To verify the efficacy of phytoestrogen supplementation combined with aerobic and resistance training on the improvement of climacteric symptoms and health-related quality of life (HRQoL) in postmenopausal women.

METHODS

From a pool of women who had participated in a 1-year intervention study and were randomly assigned to either exercise + phytoestrogen (EX + PHY) or exercise + placebo (EX + PL), a total of 31 healthy but overweight women (mean age 59.2 ± 4.8 years, body mass index 29.1 ± 3.5 kg/m2) finished the study (EX + PHY, n = 15; EX + PL, n = 16). All the following variables were measured before, after 6 months and after 12 months of intervention: body composition (fat and lean body mass, DXA), HRQoL (SF-36 questionnaire: physical and mental component summaries and subscales; and the 10-item Perceived Stress Scale questionnaire), climacteric symptoms (Kupperman Index questionnaire).

RESULTS

After 1 year of intervention, physical functioning (p = 0.003), role-emotional (p = 0.031), vitality (p = 0.007), and global health (p < 0.001) were significantly and similarly increased in both groups. Regarding climacteric symptoms, an improvement in the Kupperman index total score (p = 0.015) was observed.

CONCLUSION

Our results demonstrate that adding phytoestrogens to exercise training does not provide the additive effect for HRQoL in postmenopausal and overweight women. Moreover, exercise and phytoestrogen may interfere in the improvement of climacteric symptoms in the long term.

Soy isoflavone supplementation improves longitudinal bone growth and bone quality in growing female rats

OBJECTIVES

The aim of this study was to investigate the effects of soy isoflavone on tibia length, bone mineral density (BMD), and structural parameters in growing female rats.

METHODS

Three-week-old female Sprague-Dawley rats were randomly assigned to four experimental groups: control (CON: distilled water gavage); low-dose isoflavone (low-IF: 10 mg/kg body weight [BW]/d gavage); high-dose isoflavone (high-IF: 50 mg/kg BW/d gavage); and 17 β-estradiol (E2: subcutaneous injection of 10 μg). All animals received a soy-free diet and vaginal opening was monitored daily. After an 8-wk treatment period, bone-related parameters (alkaline phosphatase [ALP], osteocalcin [OC], N-terminal telopeptide [NTx], bone length, failure load, stiffness, BMD, and structural parameters) were analyzed.

RESULTS

Serum ALP levels of the high-IF group were higher than those of the CON group (P < 0.05); however, serum OC levels of the high-IF group were lower than those of the CON, low-IF, and E2 groups (P < 0.05). The tibias and femurs of the low-IF group were longer than those of the CON and high-IF groups (P < 0.05). Bone volume, trabecular number, and BMD of trabecular bone of the high-IF and E2 groups were higher than those of the CON and low-IF groups (P < 0.05). The trabecular thickness of the high-IF group was higher than that of the CON and low-IF groups (P < 0.05). The failure load of the high-IF group was higher than those of the CON group (P < 0.05). Age and body weight at vaginal opening of the E2 group were significantly lower than those of the CON, low-IF, and high-IF groups (P < 0.05).

CONCLUSIONS

This study suggests that 8 wk of low-dose supplementation with soy isoflavone stimulates longitudinal bone growth. Additionally, high-dose supplementation with soy isoflavone may improve bone quality (BMD and structural parameters) in growing female rats.

The Effectiveness of Combined Exercise Interventions for Preventing Postmenopausal Bone Loss: A Systematic Review and Meta-analysis

Study Design Systematic review and meta-analysis. Background It remains unclear whether exercise combining different types of physical activities (combined exercise interventions) would effectively preserve postmenopausal women's bone mineral density (BMD) at different sites. Objective To examine the impact of combined exercise interventions on lumbar spine, femoral neck, total hip, and total body BMD in postmenopausal women. Methods An electronic database search was conducted in PubMed, EMBASE, SPORTDiscus, and Web of Science up to January 1, 2016. Randomized controlled trials that conducted combined exercise interventions and reported BMD values in postmenopausal women were included. Two authors independently extracted the data from individual studies. The primary end point was the change in BMD values from baseline to follow-up. The effect sizes were estimated by the standardized mean difference (SMD) methods using fixed-effects models. Results Eleven randomized controlled trials including 1061 postmenopausal women met the inclusion criteria. The levels of between-study heterogeneity were relatively low (I²<50%). Exercise integrating different physical activities significantly increased lumbar spine (SMD, 0.170; 95% confidence interval [CI]: 0.027, 0.313; P = .019), femoral neck (SMD, 0.177; 95% CI: 0.030, 0.324; P = .018), total hip (SMD, 0.198; 95% CI: 0.037, 0.359; P = .016), and total body (SMD, 0.257; 95% CI: 0.053, 0.461; P = .014) BMD. Combined exercise interventions generated a beneficial effect on femoral neck BMD (SMD, 0.219; 95% CI: 0.034, 0.404; P = .020) in groups with women aged younger than 60 years, and significantly improved lumbar spine BMD (SMD, 0.349; 95% CI: 0.064, 0.634; P = .016) in groups with women aged 60 years or older. Conclusion Our findings suggest that combined exercise interventions appear to be effective in preserving postmenopausal women's BMD at the lumbar spine, femoral neck, total hip, and total body. Level of Evidence Therapy, level 1a. J Orthop Sports Phys Ther 2017;47(4):241-251. Epub 3 Mar 2017. doi:10.2519/jospt.2017.6969.

The role of a pulse-based diet on infertility measures and metabolic syndrome risk: protocol of a randomized clinical trial in women with polycystic ovary syndrome

Background

Polycystic Ovary Syndrome (PCOS) is an endocrine disorder in women of reproductive age with an estimated prevalence of 5–20% of premenopausal women. The clinical symptoms common to PCOS include menstrual dysfunction, hyperandrogenemia, hirsutism, polycystic ovaries, insulin resistance, and hyperinsulinemia. Women with PCOS are at an increased risk of infertility, obesity and type 2 diabetes mellitus. Insulin resistance and hyperinsulinemia are believed to be key contributing factors to the pathogenesis of PCOS; excessive amounts of insulin are directly associated with the increased ovarian production of androgens and metabolic features of PCOS. Pulse-based diets (e.g., beans, chickpeas) are associated with improved glycemic control and have insulin lowering effects. The purpose of this study is to determine whether a pulse-based diet is more effective than the diet recommended by the National Cholesterol Education Program. The primary outcomes of this study are disease measures related to PCOS, with secondary outcomes including measures related to metabolic syndrome.

Methods

Women with symptoms of PCOS will be recruited for the study and a diagnosis of PCOS will be determined by an obstetrician-gynecologist. Women with PCOS will be randomly assigned to receive either a pulse-based diet or the National Cholesterol Education Program therapeutic lifestyle changes (TLC) diet for 16 weeks while participating in an aerobic exercise program. One hundred participants will be required (drop-out rate of 32%) for recruitment to provide 80% power for detecting a significant difference in fasting glucose (p < 0.05). Measures related to infertility, metabolic syndrome, quality of life, dietary intake and physical activity will be assessed pre- and post-intervention with follow up assessment at 6- and 12-months post-intervention.

Discussion

Polycystic ovary syndrome is the most common endocrine disorder in women of reproductive age and there is currently no recommended diet for this population of women. The multidisciplinary nature of this study, including determination of measures related to metabolic syndrome, infertility and physical activity provide a comprehensive assessment of any benefits associated with a pulse-based diet in women with PCOS. The results of this study will help in providing evidence-based recommendations for the optimum diet to reduce symptoms associated with PCOS.

Trial registration

NCT01288638. Trial registered January 13, 2011.

Effects of low-dose ibuprofen supplementation and resistance training on bone and muscle in postmenopausal women: A randomized controlled trial

PURPOSE

To compare the effects of nine months of exercise training and ibuprofen supplementation (given immeditately after exercise sessions) on bone and muscle in postmenopausal women.

METHODS

In a double-blind randomized trial, participants (females: n = 90, mean age 64.8, SD 4.3 years) were assigned (computer generated, double blind) to receive supervised resistance training or stretching 3 days/week, and ibuprofen (400 mg, post-exercise) or placebo (i.e. 4 groups) for 9 months. In this proof-of-concept study the sample size was halved from required 200 identified via 90% power calculation. Baseline and post-intervention testing included: Dual energy x-ray absorptiometry (DXA) for lumbar spine, femoral neck, and total body areal bone mineral density (aBMD); geometry of proximal femur; total body lean tissue and fat mass; predicted 1-repetition maximum muscle strength testing (1RM; biceps curl, hack squat).

RESULTS

Exercise training or ibuprofen supplementation had no effects on aBMD of the lumbar spine, femoral neck, and total body. There was a significant exercise × supplement × time interaction for aBMD of Ward's region of the femoral neck (p = 0.015) with post hoc comparison showing a 6% decrease for stretching with placebo vs. a 3% increase for stretching with ibuprofen (p = 0.017). Resistance training increased biceps curl and hack squat strength vs. stretching (22% vs. 4% and 114% vs. 12%, respectively) (p < 0.01) and decreased percent body fat compared to stretching (2% vs. 0%) (p < 0.05).

CONCLUSIONS

Ibuprofen supplementation provided some benefits to bone when taken independent of exercise training in postmenopausal women. This study provides evidence towards a novel, easily accessible stimulus for enhancing bone health [i.e. ibuprofen].

Creatine supplementation in the aging population: effects on skeletal muscle, bone and brain

This narrative review aims to summarize the recent findings on the adjuvant application of creatine supplementation in the management of age-related deficits in skeletal muscle, bone and brain metabolism in older individuals. Most studies suggest that creatine supplementation can improve lean mass and muscle function in older populations. Importantly, creatine in conjunction with resistance training can result in greater adaptations in skeletal muscle than training alone. The beneficial effect of creatine upon lean mass and muscle function appears to be applicable to older individuals regardless of sex, fitness or health status, although studies with very old (>90 years old) and severely frail individuals remain scarce. Furthermore, there is evidence that creatine may affect the bone remodeling process; however, the effects of creatine on bone accretion are inconsistent. Additional human clinical trials are needed using larger sample sizes, longer durations of resistance training (>52 weeks), and further evaluation of bone mineral, bone geometry and microarchitecture properties. Finally, a number of studies suggest that creatine supplementation improves cognitive processing under resting and various stressed conditions. However, few data are available on older adults, and the findings are discordant. Future studies should focus on older adults and possibly frail elders or those who have already experienced an age-associated cognitive decline.

Effects of Creatine and Resistance Training on Bone Health in Postmenopausal Women

PURPOSE

Our primary purpose was to determine the effect of 12 months of creatine (Cr) supplementation during a supervised resistance training program on properties of bone in postmenopausal women.

METHODS

Participants were randomized (double-blind) into two groups: resistance training (3 d·wk) and Cr supplementation (0.1 g·kg·d) or resistance training and placebo (Pl). Our primary outcome measures were lumbar spine and femoral neck bone mineral density (BMD). Secondary outcome measures were total hip and whole-body BMD, bone geometric properties at the hip, speed of sound at the distal radius and tibia, whole-body lean tissue mass, muscle thickness, and bench press and hack squat strength. Forty-seven women (57 (SD, 6) yr; Cr, n = 23; Pl, n = 24) were randomized, with 33 analyzed after 12 months (Cr, n = 15; Pl, n = 18).

RESULTS

Cr attenuated the rate of femoral neck BMD loss (-1.2%; absolute change (95% confidence interval), -0.01 (-0.025 to 0.005) g·cm) compared with Pl (-3.9%; -0.03 (-0.044 to -0.017) g·cm; P < 0.05) and also increased femoral shaft subperiosteal width, a predictor of bone bending strength (Cr, 0.04 (-0.09 to 0.16) cm); Pl, -0.12 (-0.23 to -0.01) cm; P < 0.05). Cr increased relative bench press strength more than Pl (64% vs 34%; P < 0.05). There were no differences between groups for other outcome measures. There were no differences between groups for reports of serum liver enzyme abnormalities, and creatinine clearance was normal for Cr participants throughout the intervention.

CONCLUSIONS

Twelve months of Cr supplementation during a resistance training program preserves femoral neck BMD and increases femoral shaft superiosteal width, a predictor of bone bending strength, in postmenopausal women.

Soy Isoflavones and Osteoporotic Bone Loss: A Review with an Emphasis on Modulation of Bone Remodeling

Osteoporosis is an age-related disorder that affects both women and men, although estrogen deficiency induced by menopause accelerates bone loss in older women. As the demographic shifts to a more aged population, a growing number of men and women will be afflicted with osteoporosis. Since the current drug therapies available have multiple side effects, including increased risk of developing certain types of cancer or complications, a search for potential nonpharmacologic alternative therapies for osteoporosis is of prime interest. Soy isoflavones (SI) have demonstrated potential bone-specific effects in a number of studies. This article provides a systematic review of studies on osteoporotic bone loss in relation to SI intake from diet or supplements to comprehensively explain how SI affect the modulation of bone remodeling. Evidence from epidemiologic studies supports that dietary SI attenuate menopause-induced osteoporotic bone loss by decreasing bone resorption and stimulating bone formation. Other studies have also illustrated that bone site-specific trophic and synergistic effects combined with exercise intervention might contribute to improve the bioavailability of SI or strengthen the bone-specific effects. To date, however, the effects of dietary SI on osteoporotic bone loss remain inconclusive, and study results vary from study to study. The current review will discuss the potential factors that result in the conflicting outcomes of these studies, including dosages, intervention materials, study duration, race, and genetic differences. Further well-designed studies are needed to fully understand the underlying mechanism and evaluate the effects of SI on osteoporosis in humans.

Bone strength and muscle properties in postmenopausal women with and without a recent distal radius fracture

Distal radius (wrist) fracture (DRF) in women over age 50 years is an early sign of bone fragility. Women with a recent DRF compared to women without DRF demonstrated lower bone strength, muscle density, and strength, but no difference in dual-energy x-ray absorptiometry (DXA) measures, suggesting DXA alone may not be a sufficient predictor for DRF risk.

INTRODUCTION

The objective of this study was to investigate differences in bone and muscle properties between women with and without a recent DRF.

METHODS

One hundred sixty-six postmenopausal women (50-78 years) were recruited. Participants were excluded if they had taken bone-altering medications in the past 6 months or had medical conditions that severely affected daily living or the upper extremity. Seventy-seven age-matched women with a fracture in the past 6-24 months (Fx, n = 32) and without fracture (NFx, n = 45) were measured for bone and muscle properties using the nondominant (NFx) or non-fractured limb (Fx). Peripheral quantitative computed tomography (pQCT) was used to estimate bone strength in compression (BSIc) at the distal radius and tibia, bone strength in torsion (SSIp) at the shaft sites, muscle density, and area at the forearm and lower leg. Areal bone mineral density at the ultradistal forearm, spine, and femoral neck was measured by DXA. Grip strength and the 30-s chair stand test were used as estimates of upper and lower extremity muscle strength. Limb-specific between-group differences were compared using multivariate analysis of variance (MANOVA).

RESULTS

There was a significant group difference (p < 0.05) for the forearm and lower leg, with the Fx group demonstrating 16 and 19% lower BSIc, 3 and 6% lower muscle density, and 20 and 21% lower muscle strength at the upper and lower extremities, respectively. There were no differences between groups for DXA measures.

CONCLUSIONS

Women with recent DRF had lower pQCT-derived estimated bone strength at the distal radius and tibia and lower muscle density and strength at both extremities.