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BACKGROUND: Short-term (5 min) heart rate variability (HRV) analysis is widely used in assessing autonomic nervous system activity during exercise. While shortening the HRV measurement duration can help improve its application efficiency, its accuracy needs to be verified. This study investigated the agreement between ultra-short-term (UST) HRV (3 or 4 min) and standard 5 min HRV and explored the optimal recording duration under resting and post-exercise conditions. METHODS: Fourteen participants exercised on a cycle ergometer at 60% of their maximum peak power. Data were collected during the rest condition (Pre-E) and three post-exercise conditions (Post-E1, Post-E2, and Post-E3), with indicators of the standard deviation (SDNN) of the ultra-short and short-term RR intervals and the root mean square (RMSSD) of the continuous difference between RR intervals. Repeated measures ANOVA, Cohen's d statistic, Bland-Altman analysis, and interclass correlation coefficients (ICC) assessed the agreement between UST-HRV and ST-HRV. RESULTS: The consistency results of SDNN and RMSSD in resting and post-exercise were different. At the Pre-E, Post-E2, and Post-E3 phases, no statistical differences for SDNN and RMSSD were observed, with ICCs surpassing 0.9, indicating a high level of agreement. However, at Post-E2, there was a significant difference between 3 min RMSSD and 5 min RMSSD (p < 0.05), as well as between 3 min SDNN, 4 min SDNN, and 5 min SDNN (p < 0.05). Furthermore, the limits of agreement were observed to decrease as the time duration increased in Bland-Altman plots. CONCLUSIONS: UST-HRV analysis is a reliable substitute for standard 5 min HRV assessment, particularly during resting conditions. For post-exercise measurements, assessing the appropriateness of a 3- or 4 min duration based on the exercise's length is recommended to ensure accuracy and reliability.
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Background: Physical exertion during exercise often leads to increased oxidative stress and inflammatory responses, significantly affecting physical performance. Current strategies to mitigate these effects are limited by their effectiveness and potential side effects. Molecular hydrogen (H2) has gained attention for its antioxidant and anti-inflammatory properties. Studies have suggested that H2 supplementation contributes to antioxidant potential and anti-fatigue during exercise, but the variance in the observations and study protocols is presented across those studies. Objective: This systematic review and meta-analysis aimed to comprehensively characterize the effects of H2 supplementation on physical performance (i.e., endurance, muscular strength, and explosive power), providing knowledge that can inform strategies using H2 for enhancing physical performance. Methods: We conducted a literature search of six databases (PubMed, Web of Science, Medline, Sport-Discus, Embase, and PsycINFO) according to the PRISMA guidelines. The data were extracted from the included studies and converted into the standardized mean difference (SMD). After that, we performed random-effects meta-analyses and used the I 2 statistic to evaluate heterogeneity. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the quality of the evidence obtained from this meta-analysis. Results: In total, 27 publications consisting of 597 participants were included. The search finally included aerobic endurance, anaerobic endurance, muscular strength, lower limb explosive power, rating of perceived exertion (RPE), blood lactate (BLA), and average heart rate (HRavg) in the effect size (ES) synthesis. The ES of H2 on aerobic endurance, including VÌO2max (SMD = 0.09, p = 0.394; I 2 = 0%) and aerobic endurance exercise (SMD = 0.04, p = 0.687; I 2 = 0%), were not significant and trivial; the ES of H2 on 30 s maximal anaerobic endurance (SMD = 0.19, p = 0.239; I 2 = 0%) was not significant and trivial; the ES of H2 on muscular strength (SMD = 0.19, p = 0.265; I 2 = 0%) was not significant and trivial; but the ES of H2 on lower limb explosive power (SMD = 0.30, p = 0.018; I 2 = 0%) was significant and small. In addition, H2 reduces RPE (SMD = -0.37, p = 0.009; I 2 = 58.0%) and BLA (SMD = -0.37, p = 0.001; I 2 = 22.0%) during exercise, but not HRavg (SMD = -0.27, p = 0.094; I 2 = 0%). Conclusion: These findings suggest that H2 supplementation is favorable in healthy adults to improve lower limb explosive power, alleviate fatigue, and boost BLA clearance, but may not be effectively improving aerobic and anaerobic endurance and muscular strength. Future studies with more rigorous designs are thus needed to examine and confirm the effects of H2 on these important functionalities in humans. Systematic review registration: http://www.crd.york.ac.uk/PROSPERO.
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During pregnancy, germline development is vital for maintaining the continuation of species. Recent studies have shown increased pregnancy risks in COVID-19 patients at the perinatal stage. However, the potential consequence of infection for reproductive quality in developing fetuses remains unclear. Here, we analyze the transcriptome and DNA methylome of the fetal germline following maternal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We find that infection at early gestational age, a critical period of human primordial germ cell specification and epigenetic reprogramming, trivially affects fetal germ cell (FGC) development. Additionally, FGC-niche communications are not compromised by maternal infection. Strikingly, both general and SARS-CoV-2-specific immune pathways are greatly activated in gonadal niche cells to protect FGCs from maternal infection. Notably, there occurs an "in advance" development tendency in FGCs after maternal infection. Our study provides insights into the impacts of maternal SARS-CoV-2 infection on fetal germline development and serves as potential clinical guidance for future pandemics.
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COVID-19 , Feto , Células Germinativas , SARS-CoV-2 , Humanos , Feminino , COVID-19/virologia , COVID-19/imunologia , COVID-19/patologia , Gravidez , Células Germinativas/virologia , Feto/virologia , Complicações Infecciosas na Gravidez/virologia , Complicações Infecciosas na Gravidez/patologia , Gônadas/virologia , Transcriptoma/genética , Masculino , Metilação de DNA/genética , Epigênese GenéticaRESUMO
Transcription factors (TFs) play important roles in early embryonic development, but factors regulating TF action, relationships in signaling cascade, genome-wide localizations, and impacts on cell fate transitions during this process have not been clearly elucidated. In this study, we used uliCUT&RUN-seq to delineate a TFAP2C-centered regulatory network, showing that it involves promoter-enhancer interactions and regulates TEAD4 and KLF5 function to mediate cell polarization. Notably, we found that maternal retinoic acid metabolism regulates TFAP2C expression and function by inducing the active demethylation of SINEs, indicating that the RARG-TFAP2C-TEAD4/KLF5 axis connects the maternal-to-zygotic transition to polarization. Moreover, we found that both genomic imprinting and SNP-transferred genetic information can influence TF positioning to regulate parental gene expressions in a sophisticated manner. In summary, we propose a ternary model of TF regulation in murine embryonic development with TFAP2C as the core element and metabolic, epigenetic, and genetic information as nodes connecting the pathways.
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Implantação do Embrião , Regulação da Expressão Gênica no Desenvolvimento , Fator de Transcrição AP-2 , Fatores de Transcrição , Animais , Feminino , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Implantação do Embrião/genética , Desenvolvimento Embrionário/genética , Redes Reguladoras de Genes , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição de Domínio TEA/metabolismo , Fator de Transcrição AP-2/metabolismo , Fator de Transcrição AP-2/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Tretinoína/metabolismoRESUMO
Embryos, originating from fertilized eggs, undergo continuous cell division and differentiation, accompanied by dramatic changes in transcription, translation, and metabolism. Chromatin regulators, including transcription factors (TFs), play indispensable roles in regulating these processes. Recently, the trophoblast regulator TFAP2C was identified as crucial in initiating early cell fate decisions. However, Tfap2c transcripts persist in both the inner cell mass and trophectoderm of blastocysts, prompting inquiry into Tfap2c's function in post-lineage establishment. In this study, we delineate the dynamics of TFAP2C during the mouse peri-implantation stage and elucidate its collaboration with the key lineage regulators CDX2 and NANOG. Importantly, we propose that de novo formation of H3K9me3 in the extraembryonic ectoderm during implantation antagonizes TFAP2C binding to crucial developmental genes, thereby maintaining its lineage identity. Together, these results highlight the plasticity of the chromatin environment in designating the genomic binding of highly adaptable lineage-specific TFs and regulating embryonic cell fates.
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Fator de Transcrição CDX2 , Linhagem da Célula , Cromatina , Regulação da Expressão Gênica no Desenvolvimento , Fator de Transcrição AP-2 , Animais , Cromatina/metabolismo , Camundongos , Linhagem da Célula/genética , Fator de Transcrição AP-2/metabolismo , Fator de Transcrição AP-2/genética , Fator de Transcrição CDX2/metabolismo , Fator de Transcrição CDX2/genética , Proteína Homeobox Nanog/metabolismo , Proteína Homeobox Nanog/genética , Blastocisto/metabolismo , Blastocisto/citologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Feminino , Histonas/metabolismo , Diferenciação Celular/genética , Ectoderma/metabolismo , Ectoderma/citologia , Desenvolvimento Embrionário/genéticaRESUMO
Complex training (CT) is a combination training method that alternates between performing high-load resistance training (RT) and plyometric training within one single session. The study aimed to examine the effects of CT on lower-limb strength and power of elite female modern pentathlon athletes under the new modern pentathlon format and competition rules. Ten female participants (age: 23.55 ± 2.22 years, weight: 60.59 ± 3.87 kg, height: 169.44 ± 4.57 cm, and training experience: 6.90 ± 2.08 years) of the national modern pentathlon team completed 8 weeks of RT as followed by 8 weeks of CT, with 2 weeks of break. Then, the participants conducted 8 weeks of CT, which included RT combined with plyometric training (e.g., drop jump and continuous jump). All stages of training were designed by the linear strength training period theories, requiring participants to train twice for the first 4 weeks and three times for the second 4 weeks. The one-repetition maximum (1RM) of squat, isometric mid-thigh pull (IMTP), counter-movement jump (CMJ), squat jump (SJ), pre-stretch augmentation percentage (PSAP), and reaction strength index (RSI) were assessed before and after both RT and CT training. One-way repeated-measure ANOVA models revealed that the 1RM of squat was significantly improved (p < 0.001) after RT as compared to pre-RT. No significant improvement in IMTP (p = 0.055), CMJ (p = 0.194), SJ (p = 0.692), PSAP (p = 0.087), and RSI (p = 0.238) was not observed. After CT, 1RM of squat (p < 0.001), IMTP (p < 0.035), CMJ (p < 0.001), SJ (p < 0.008), RSI (p < 0.006) were significant improved as compared to pre-RT, post-RT and pre-CT, while significant improvements in PSAP were observed as compared to pre-RT (p = 0.003) and pre-CT (p = 0.027), but not to post-RT (p = 0.156). This pilot study showed the promise of CT following RT to improve lower-limb strength and power in elite female modern pentathlon athletes. The findings are worthwhile to be confirmed in future studies with larger sample size and randomized design.
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Objective: This study examined the effects of 12-week complex training (CT) programs on professional firefighters' occupational activities, strength, and power. Methods: Thirty men professional firefighters were randomly assigned to the CT group (n = 15) and control group (n = 15). The CT group performed complex training and the control group completed resistance training (RT) twice a week over 12 weeks. The occupational activities, strength, and power were assessed at baseline and immediately after the intervention by measuring the performance of 100 m load-bearing run (100 m LR), 60 m shoulder ladder run (60 m SLR), 5 m × 20 m shuttle run (5 m × 20 m SR), 4th-floor climbing rope (4th-floor CR), countermovement jump with arm swing (CMJas), seated medicine-ball throw (SMT), one-repetition maximum bench press (1RM BP), and one-repetition maximum back squat (1RM BS). Results: The results showed that compared to RT, CT induced significantly greater improvements in 60 m SLR (p = 0.007), 4th-floor CR (p = 0.020), CMJas (p = 0.001), and SMT (p < 0.001). Conclusion: These findings suggest that CT is a novel intervention with great promise of improving professional firefighters' occupational activities, strength, and power.
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Objectives: To investigate the effect of combined balance and plyometric training on knee function and proprioception of elite badminton athletes. Methods: Sixteen elite male badminton players (age: 20.5 ± 1.1 years, height: 177.8 ± 5.1 cm, weight: 68.1 ± 7.2 kg, and training experience: 11.4 ± 1.4 years) volunteered to participate and were randomly assigned to a combined balance and plyometric training (CT) (n = 8) and plyometric (PT) group (n = 8). The CT group performed balance combined with plyometric training three times a week over 6 weeks (40 min of plyometrics and 20 min of balance training); while the PT group undertook only plyometric training for the same period (3-4 sets × 8-12 reps for each exercise). Both groups had the same technical training of badminton. Results: The knee function and proprioception were assessed at baseline and after the intervention by measuring the performance of single-legged hop tests (LSIO, LSIT, LSIC, LSIS), standing postural sway (COPAP, COPML), and LSI of dominant leg and non-dominant leg. The results showed that as compared to PT, CT induced significantly greater improvements in LSIT and LSIS (p < 0.001) and significant greater percent increase in NAP (p = 0.011). The changes in LSIO, LSIC, DAP, NAP, LSIAP, DML, NML, and LSIML induced by CT did not differ from that induced by PT (p > 0.213). Conclusion: In elite badminton players, intervention using CT holds great promise to augment the benefits for knee function compared to the intervention using PT only, and at the same time, with at least comparable benefits for proprioception. Future studies are needed to examine and confirm the results of this study.
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Introduction: Accurately predicting the competitive performance of elite athletes is an essential prerequisite for formulating competitive strategies. Women's all-around speed skating event consists of four individual subevents, and the competition system is complex and challenging to make accurate predictions on their performance. Objective: The present study aims to explore the feasibility and effectiveness of machine learning algorithms for predicting the performance of women's all-around speed skating event and provide effective training and competition strategies. Methods: The data, consisting of 16 seasons of world-class women's all-around speed skating competition results, used in the present study came from the International Skating Union (ISU). According to the competition rules, distinct features are filtered using lasso regression, and a 5,000 m race model and a medal model are built using a fivefold cross-validation method. Results: The results showed that the support vector machine model was the most stable among the 5,000 m race and the medal models, with the highest AUC (0.86, 0.81, respectively). Furthermore, 3,000 m points are the main characteristic factors that decide whether an athlete can qualify for the final. The 11th lap of the 5,000 m, the second lap of the 500 m, and the fourth lap of the 1,500 m are the main characteristic factors that affect the athlete's ability to win medals. Conclusion: Compared with logistic regression, random forest, K-nearest neighbor, naive Bayes, neural network, support vector machine is a more viable algorithm to establish the performance prediction model of women's all-around speed skating event; excellent performance in the 3,000 m event can facilitate athletes to advance to the final, and athletes with outstanding performance in the 500 m event are more likely competitive for medals.
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The study aimed to investigate the effect of combined balance and plyometric training on dynamic balance and quickness performance of elite badminton athletes. Sixteen elite male badminton players volunteered to participate and were randomly assigned to a balance-plyometric group (PB: n = 8) and plyometric group (PT: n = 8). The PB group performed balance combined with plyometric training three times a week over 6 weeks (40 min of plyometrics and 20 min of balance training); while the PT group undertook only plyometric training for the same period (3-4 sets × 8-12 reps for each exercise). Both groups were given the same technical training (badminton techniques for 6 days a week). The dynamic stability and quick movement ability were assessed at baseline and after the intervention by measuring the performance of dynamic posture stability test (DPSI and COP), T-running test and hexagon jump test. The results showed that compared to PT, PB induced significantly greater improvements in F-DPSI, L-DPSI (p = 0.003, 0.025, respectively), F-COPAP, F-COPML, F-COPPL, L-COPPL (p = 0.024, 0.002, 0.029, 0.043, respectively), T-running test and hexagon jump test (p < 0.001). The change in L-DPSI, L-COPAP, L-COPML did not differ between PB and PT (p > 0.907). The findings suggest that combined training holds great promise of improving the dynamic balance and quickness performance in elite badminton athletes.
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Desempenho Atlético , Exercício Pliométrico , Esportes com Raquete , Futebol , Teste de Esforço , Humanos , Masculino , Força Muscular , Exercício Pliométrico/métodosRESUMO
Powdery mildew, caused by Sphaerotheca sp., annually causes severe losses in yield and quality in Rosa roxburghii production areas of southwest China. In this study, the role of the co-application of allicin and chitosan in the resistance of R. roxburghii against powdery mildew and its effects on growth, yield and quality of R. roxburghii were investigated. The laboratory toxicity test results show that allicin exhibited a superior antifungal activity against Sphaerotheca sp. with EC50 value of 148.65 mg kg-1. In the field, the foliar application of allicin could effectively enhance chitosan against powdery mildew with control efficacy of 85.97% by spraying 5% allicin microemulsion (ME) 100-time liquid + chitosan 100-time liquid, which was significantly (p < 0.01) higher than 76.70% of allicin, 70.93% of chitosan and 60.23% of polyoxin. The co-application of allicin and chitosan effectively enhanced the photosynthetic rate and chlorophyll of R. roxburghii compared with allicin, chitosan or polyoxin alone. Moreover, allicin used together with chitosan was more effective than allicin or chitosan alone in enhancing R. roxburghii plant growth and fruit yield as well as improving R. roxburghii fruit quality. This work highlights that the co-application of allicin and chitosan can be used as a green, cost-effective and environmentally friendly alternative strategy to conventional antibiotics for controlling powdery mildew of R. roxburghii.
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OBJECTIVE: Physical training (PT, e.g., Tai Chi and strength training) has been demonstrated to improve balance control and prevent falls. Recently, exergame intervention (EI) has emerged to prevent falls by enhancing both physical and cognitive functions in older adults. Therefore, we aim to quantitatively assess and compare the effects of PT and EI on the performance of balance control and fall prevention in healthy older adults via meta-analysis. METHODS: A search strategy based on the PICOS principle was used to find the publication in the databases of PubMed, EMBASE, Web of Science, Cochrane Library, and MEDLINE. The quality and risk of bias in the studies were independently assessed by two researchers. RESULTS: Twenty studies consisting of 845 participants were included. Results suggested that as compared to PT, EI induced greater improvement in postural control (sway path length, SMD = - 0.66, 95% CI - 0.91 to - 0.41, P < 0.001, I2 = 0%; sway speed, SMD = - 0.49, 95% CI - 0.71 to - 0.27, P < 0.001, I2 = 42%) and dynamic balance (SMD = - 0.19, 95% CI - 0.35 to - 0.03, P = 0.02, I2 = 0%) in healthy older adults. The EI with 90-119 min/week for more than 8-week significantly reduced falls. Subgroup analyses revealed that exergames, which were designed by the two principles of repeatedly performing diversified tasks and gradually increase the difficulty of the task, induced significant effects in improving balance control and falls prevention respectively (P = 0.03, P = 0.009). In addition, intervention that combines EI and PT induced significant improvement in postural control (P = 0.003). CONCLUSION: The exergame intervention, especially the combination of EI and PT, is a promising strategy to improve balance control and reduce falls in healthy older adults. Future studies with rigorous design, larger sample size, and follow-up assessments are needed to further assess the effectiveness of diverse exergame interventions in fall prevention and to quantify the "dose-effect" relationship, as well as the carry-over effect of such intervention, which will ultimately help optimize the rehabilitative strategies to improve balance control and prevent falls.
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Jogos Eletrônicos de Movimento , Treinamento Resistido , Idoso , Exercício Físico , Humanos , Equilíbrio PosturalRESUMO
PURPOSE: The purpose exposure to hypoxia in high altitudes severely impairs the sleep quality and the related cardiovascular regulation, including the blood pressure (BP) regulation. BP regulation depends upon the continuous interaction of components over multiple temporal scales. As such, the dynamics of BP fluctuation are complex, and BP complexity has been linked to several pathological events. However, the effects of the exposure to hypoxia on BP complexity during sleep remain unknown. METHODS: Twenty-five younger men naïve to high-altitude sleep (apnea severity as assessed by hypoxia apnea index (AHI): normal=8; moderate=9; severe=8) completed one nocturnal sleep under each of the three altitudes: 0 (ie, baseline), 2000, and 4000 m. The sleep characteristics and oxygen saturation (ie, SpO2) were assessed using polysomnography (PSG). The beat-to-beat BP fluctuation was recorded using a finger-blood-pressure sensor. Multiscale entropy (MSE) was used to characterize the complexity of systolic (SBP) and diastolic (DBP) BP fluctuations, and lower MSE reflected lower complexity. RESULTS: Compared to 0-m condition, SBP (p=0.0003) and DBP (F=12.1, p=0.0002) complexity, SpO2 (p<0.0001) and REM ratio (p<0.0090) were decreased, AHI was increased (p=0.0004) in 2000-m and even more in 4000-m conditions. In addition, lower BP complexity was associated with greater AHI (r=-0.66~0.52, p=0.0010), lower SpO2 (r=0.48~0.51, p=0.0100~0.0200) and lower REM ratio (r=0.48~0.52, p=0.0200). Participants with greater percent reduction in BP complexity between altitudes had greater percent reduction in REM ratio and SpO2 (r=0.38~0.45, p=0.0090~0.0200), after adjustment for age, BMI, baseline apnea and altitude. CONCLUSION: These results suggested that the characterization of BP complexity may provide novel insights into the underlying mechanisms through which the exposure to hypoxia affects cardiovascular health during sleep, as well as sleep quality. This BP complexity may serve as a novel marker to help the management of cardiovascular health and sleep quality in high-altitude living.
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The study aimed to investigate the effect of combined balance and plyometric training on the change of direction (COD) performance of badminton athletes. Sixteen elite male badminton players volunteered to participate and were randomly assigned to a balance-plyometric group (BP: n = 8) and plyometric group (PL: n = 8). The BP group performed balance combined with plyometric training three times a week over 6 weeks; while the PL group undertook only plyometric training three times a week during the same period. Meanwhile, both groups were given the same technical training. All participants were tested to assess the COD ability before and after the training period: Southeast Missouri (SEMO) test and 5-0-5 test, dynamic balance ability (Y-Balance test, YBT), and reactive strength index (RSI). Repeated-measure ANOVA revealed that after the intervention there was a significant time × group interaction for 5-0-5 COD test, YBT of both legs and RSI (p < 0.05, partial η2 = 0.26-0.58) due to the better performance observed at post-test compared with a pre-test for the BP group [effect size (ES) = 1.20-1.76], and the improvement was higher than that of the PL group. The change in SEMO test did not differ between BP and PL (p < 0.159, partial η2= 0.137), but the magnitude of the with-group improvement for BP (ES = 1.55) was higher than that of PL (ES = 0.81). These findings suggest that combined training could further improve the COD performance of badminton athletes than plyometric training alone and might provide fitness trainers a more efficient COD training alternative.
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Background: Recently, considerable research has been conducted to study the effects of transcranial direct current stimulation (tDCS) on balance control in older adults. We completed a comprehensive systematic review and meta-analysis to assess the efficacy of tDCS on balance control in this population. Methods: A search strategy based on the PICOS principle was used to find the literatures in the databases of PubMed, EMBASE, EBSCO, Web of Science. The quality and risk of bias in the studies were independently assessed by two researchers. Results: Ten studies were included in the systematic review. A meta-analysis was completed on six of these ten, with a total of 280 participants. As compared to sham (i.e., control), tDCS induced significant improvement with low heterogeneity in balance control in older adults. Specifically, tDCS induced large effects on the performance of the timed-up-and-go test, the Berg balance scale, and standing postural sway (e.g., sway area) and gait (e.g., walking speed) in dual task conditions (standardized mean differences (SMDs) = -0.99~3.41 95% confidence limits (CL): -1.52~4.50, p < 0.006, I 2 < 52%). Moderate-to-large effects of tDCS were also observed in the standing posture on a static or movable platform (SMDs = 0.37~1.12 95%CL: -0.09~1.62, p < 0.03, I 2 < 62%). Conclusion: Our analysis indicates that tDCS holds promise to promote balance in older adults. These results warrant future studies of larger sample size and rigorous study design and results report, as well as specific research to establish the relationship between the parameter of tDCS and the extent of tDCS-induced improvement in balance control in older adults.