Effect of Protein Supplementation Combined With Resistance Training in Gait Speed in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: We aimed to evaluate the effectiveness of the combination of protein supplementation and resistance training (RT), compared with RT alone or combined with a placebo, in improving gait speed. METHODS: We searched PubMed, Web of Science, Cochrane Library, and SPORTDiscus databases, and 18 randomized controlled trials with 1,147 older participants were included for meta-analysis. Data were pooled as the effect sizes (Hedges' g) with 95% confidence interval (CI) of the gait speed (in meters per second). The random-effect meta-analysis, subgroup analyses, meta-regression, and sensitivity analysis were conducted. RESULTS: The combination of protein supplementation and RT significantly improved gait speed (Hedges' g: 0.52 m/s, 95% confidence interval [0.17, 0.86], p = .005; I2 = 86.5%) compared with the RT alone. The subgroup analyses revealed that the significant improvement in gait speed postprotein intervention plus RT was observed only in participants who consumed protein after RT (Hedges' g: 0.90 m/s, 95% confidence interval [0.46, 1.33], p = .001; I2 = 79.6%). The pooled result did not significantly change after excluding any single study at one time or excluding smaller studies with large effect sizes. CONCLUSIONS: Protein supplementation combined with RT could significantly improve the gait speed of older adults compared with RT alone. This positive effect is more pronounced in people who consume protein after RT.

Long-term exercise training and inflammatory biomarkers in healthy subjects: a meta-analysis of randomized controlled trials.

Objective: This meta-analysis investigated the effect of long-term exercise training (ET) including aerobic, resistance, and multicomponent ET on the levels of inflammatory biomarkers in randomized controlled trials (RCTs) involving healthy subjects. Methods: We searched seven databases for articles until May 1st, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 16.0. Result: Thirty-eight studies were included in the meta-analysis, involving 2,557 healthy subjects (mean age varies from 21 to 86 years). Long-term ET induced significantly decreased in the levels of interleukin-6 (IL-6) (SMD -0.16, 95% CI -0.30 to -0.03, p = 0.017), C-reactive protein (CRP) (SMD -0.18, 95% CI -0.31 to -0.06, p = 0.005), as well as tumor necrosis factor alpha (TNFα) (SMD -0.43, 95% CI -0.62 to -0.24, p < 0.001). Subgroup analysis revealed that Long-term ET conducted for more than 12 weeks and exercise of moderate intensity had greater anti-inflammatory effects. Meta-regression analysis showed that the reduction in CRP level induced by long-term ET was weakened by increasing exercise intensity. Conclusion: Long-term ET induced significant anti-inflammatory effects in healthy subjects. Long-term ET-induced anti-inflammatory effects were associated with exercise of moderate intensity and training conducted for more than 12 weeks.Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/# myprospero, PROSPERO, identifier CRD42022346693.

Effects of physical exercise on biomarkers of oxidative stress in healthy subjects: A meta-analysis of randomized controlled trials.

This meta-analysis investigated the effect of physical exercise (PE) on the levels of oxidative biomarkers in randomized controlled trials (RCTs) involving healthy subjects. We searched five databases for articles until May 1, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 11.0, involving ten articles. According to the results of the meta-analysis, PE had no significant effect on superoxide dismutase (SOD), glutathione peroxidase, and catalase levels. PE induced significant increase in total antioxidant status (standardized mean difference [SMD] 1.53, 95% CI 0.73-2.32), and PE could significantly reduce the level of malondialdehyde (MDA) (SMD -1.11, 95% CI -2.15 to -0.06). Sensitivity analyses and subgroup analyses showed that male participants, body mass index (BMI) <25, exercise duration between 1 and 12 weeks, resistance exercise or multicomponent exercise, and exercise of low or moderate intensity were associated with a significant PE-induced decrease in MDA concentrations. Meta-regression analysis identified the age of the participants as a confounder of the effect of PE on SOD levels. The older age of the subjects was associated in a gradient fashion with incident SOD levels. Further RCTs are required to investigate the optimal PE protocol for people of different ages and BMI as well as the effect of PE on oxidative stress.

Low skeletal muscle mass index and all-cause mortality risk in adults: A systematic review and meta-analysis of prospective cohort studies.

OBJECTIVE: The relationship between low skeletal muscle mass index (SMI) and all-cause mortality risk in the general adults remains unclear. Our study was conducted to examine and quantify the associations between low SMI and all-cause mortality risks. METHODS: PubMed, Web of Science, and Cochrane Library for primary data sources and references to relevant publications retrieved until 1 April 2023. A random-effect model, subgroup analyses, meta-regression, sensitivity analysis, and publication bias were conducted using STATA 16.0. RESULTS: Sixteen prospective studies were included in the meta-analysis of low SMI and the risk of all-cause mortality. A total of 11696 deaths were ascertained among 81358 participants during the 3 to 14.4 years follow-up. The pooled RR of all-cause mortality risk was 1.57 (95% CI, 1.25 to 1.96, P < 0.001) across the lowest to the normal muscle mass category. The results of meta-regression showed that BMI (P = 0.086) might be sources of heterogeneity between studies. Subgroup analysis showed that low SMI was significantly associated with an increased risk of all-cause mortality in studies with a body mass index (BMI) between 18.5 to 25 (1.34, 95% CI, 1.24-1.45, P<0.001), 25 to 30 (1.91, 95% CI, 1.16-3.15, P = 0.011), and over 30 (2.58, 95% CI, 1.20-5.54 P = 0.015). CONCLUSIONS: Low SMI was significantly associated with the increased risk of all-cause mortality, and the risk of all-cause mortality associated with low SMI was higher in adults with a higher BMI. Low SMI Prevention and treatment might be significant for reducing mortality risk and promoting healthy longevity.

Prevalence of Achilles tendinopathy in physical exercise: A systematic review and meta-analysis.

This comprehensive systematic review and meta-analysis assessed the prevalence of Achilles tendinopathy (AT) in physical exercise (PE). Specifically, we estimate the overall risk of AT in physical exercise and compare sport-specific estimates of AT risk. PubMed, Web of Science, Cochrane Library, and SPORTDiscus were searched before the 1st of October 2021. Random-effects, subgroup analysis, sensitivity analysis and meta-regressions were conducted, involving 16 publications. This meta-analysis found that the overall prevalence of AT was 0.06 (95%CI, 0.04-0.07). The prevalence of Achilles tendon rupture was 0.03 (95%CI, 0.02-0.05). Subgroup analysis showed that the prevalence of AT increased with age, the highest among the group aged over 45 (0.08; 95%CI, 0.04-0.11), and the lowest among the group under 18 years old (0.02; 95%CI, 0.01-0.03). The gymnastics and ball games had the highest prevalence of AT, at (0.17; 95%CI, 0.14-0.20) and (0.06; 95%CI, 0.02-0.11), respectively. The prevalence of AT in athletes (0.06; 95%CI, 0.04-0.08) was higher than that of amateur exercisers (0.04; 95%CI, 0.02-0.06) and there was no difference in the prevalence of AT between males and females. There are differences in the prevalence of AT in different ages, sport events and characteristics of participants. This systematic review and meta-analysis suggested that it was necessary to pay more attention to AT in people who were older or engaged in gymnastics.

Lifestyle intervention during pregnancy in patients with gestational diabetes mellitus and the risk of neonatal hypoglycemia: A systematic review and meta-analysis.

Objective: Neonatal hypoglycemia is a severe adverse consequence of infants born to mothers with gestational diabetes mellitus (GDM), which can lead to neonatal mortality, permanent neurological consequences, and epilepsy. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to explore the effect of lifestyle intervention during pregnancy in women with GDM on the risk of neonatal hypoglycemia. Methods: PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus databases were searched by 1st April 2022. Data were pooled as the risk ratio (RR) with 95% CIs of neonatal hypoglycemia. Random-effects, subgroup analyses, meta-regression analysis, and leave-one-out analysis were conducted, involving 18 RCTs. Results: Prenatal lifestyle intervention could significantly reduce the risk of neonatal hypoglycemia (RR: 0.73, 95% CI: 0.54-0.98, P = 0.037). Subgroup analysis further demonstrated that the reduced risk of neonatal hypoglycemia was observed only when subjects were younger than 30 years, initiated before the third trimester, and with dietary intervention. Meta-regression analysis revealed that the risk of neonatal hypoglycemia post lifestyle intervention was lower in mothers with lower fasting glucose levels at trial entry. Conclusion: We found that prenatal lifestyle intervention in women with GDM significantly reduced the risk of neonatal hypoglycemia. Only lifestyle intervention before the third trimester of pregnancy, or dietary intervention only could effectively reduce the risk of neonatal hypoglycemia. Future studies are required to explore the best pattern of lifestyle intervention and to determine the proper diagnostic criteria of GDM in the first/second trimester of pregnancy. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#myprospero, PROSPERO, identifier: CRD42021272985.

The effect of physical exercise on circulating brain-derived neurotrophic factor in healthy subjects: A meta-analysis of randomized controlled trials.

OBJECTIVE: To investigate how physical exercise (PE) would affect brain-derived neurotrophic factor (BDNF) in randomized controlled trials (RCTs) of healthy subjects. METHODS: Seven databases (PubMed, Web of Science, Cochrane, Embase, PsycINFO, CINAHL, SPORTDiscus) were searched for RCTs assessing the effects of PE on serum and/or plasma BDNF until December 18, 2021. Meta-analysis was performed by random-effects method with standardized mean difference (SMD) and 95% confidence intervals (CIs). Subgroup analysis and meta-regression analysis were conducted to investigate the potential source of heterogeneity. Trim and fill method, and leave-one-out cross-validation were conducted. RESULTS: Eventually, 21 articles, involving 809 participants, were included in the meta-analysis. Overall, both acute (5 trials, SMD: 1.20, 95% CI: 0.36 to 2.04, p = .005) and long-term (17 trials, SMD: 0.68, 95% CI: 0.27 to 1.08, p = .001) PE had significant positive effects on BDNF levels. Via subgroup analysis, studies of long-term PE with larger sample sizes, female participants, participants older than 60 years, and aerobic exercise contributed to a more pronounced improvement on BDNF levels than that found when all studies were combined. CONCLUSION: Both acute and long-term PE had significant positive effects on circulating BDNF in healthy subjects. This review suggests that acute exercise and long-term aerobic exercise are powerful forms of PE to enhance neurotrophic effect, especially for female subjects or subjects over 60 years.