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Background: It has been suggested that higher levels of fundamental motor skills (FMS) promote the physical health of preschool-aged children. The impacts of structured and unstructured interventions on FMS in children aged 10-16 years have been widely acknowledged in previous studies. However, there is a lack of relevant studies in preschool-aged children. Objective: This meta-analysis aimed to compare the effects of structured and unstructured interventions on FMS in preschool-aged children. Methods: The PubMed, Web of Science, and Google Scholar databases were searched from inception to 1 November 2023 to identify experiments describing structured and unstructured interventions for FMS in preschool-aged children. The Downs and Black Checklist was used to assess the risk of bias. A random effects model was used for the meta-analysis to evaluate the pooled effects of interventions on FMS. Subgroup analyses based on the duration and characteristics of the intervention were conducted to identify sources of heterogeneity. Results: A total of 23 studies with 4,068 participants were included. There were 12 studies examining structured interventions, 9 studies examining unstructured interventions, and 6 studies comparing structured vs. unstructured interventions. The risk of bias in the included studies was generally low. All interventions significantly improved FMS in preschool-aged children compared to control treatments (p < 0.05). Structured interventions had more significant effects on locomotor skills (LMSs) in preschool-aged children than unstructured interventions (Hedges' g = 0.44, p = 0.04). The effects of structured interventions were strongly influenced by the total intervention duration, such that long-term interventions were more effective (Hedge's g = 1.29, p < 0.001). Conclusion: Structured interventions play a crucial role in enhancing FMS among young children, especially when considering LMSs. These interventions require consistent and repeated practice over time to reach proficiency. Systematic review registration: PROSPERO, identifier number CRD42023475088, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023475088.
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Destreza Motora , Preescolar , Femenino , Humanos , Masculino , Destreza Motora/fisiologíaRESUMEN
OBJECTIVE: To investigate the "supercompensation" effect of preschoolers during the coronavirus disease 2019 lockdown by comparing the changes in physical activity (PA), psychological, and sleep indicators before and after the lockdown. METHODS: A total of 127 children (aged 3-6 years) were recruited. Before and after the lockdown, the children's PA levels were measured using the ActiGraph GT3X+, and their psychological and sleep indicators were measured using the Strengths and Difficulties Questionnaire (SDQ) and Child Sleep Habit Questionnaire (CSHQ), respectively. RESULTS: Regarding PA, the children's total physical activity, low-intensity physical activity, and medium-intensity physical activity (MVPA) were higher after the lockdown than before the lockdown, with significant differences in MVPA (p < 0.05). Regarding psychology, the children's SDQ and multidimensional scores were better after the lockdown than before the lockdown, with a significant difference in SDQ scores (p < 0.05). Regarding sleep, the children's CSHQ scores were better after the lockdown than before the lockdown, with a highly significant difference in CSHQ scores (p < 0.01). CONCLUSION: After lockdown, children's PA, psychological, and sleep effects were "supercompensated." In particular, the PA of preschoolers before, during, and after the lockdown may show a "baseline-inhibition-supercompensation" process.
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COVID-19 , Ejercicio Físico , Sueño , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/psicología , Niño , Masculino , Femenino , Preescolar , Ejercicio Físico/psicología , Encuestas y Cuestionarios , Cuarentena/psicología , Control de Enfermedades Transmisibles/métodosRESUMEN
OBJECTIVE: This study aims to elucidate the doseâresponse relationship between 24-h activity behaviors and body fat percentage (BFP) in Chinese preschool children using a compositional isotemporal substitution model (ISM). METHODS: In a cross-sectional design, 881 children aged 3-6 from urban and rural areas of Jiangxi Province were sampled. Activity behaviors, including sedentary behavior (SB), low-intensity physical activity (LPA), and moderate- to high-intensity physical activity (MVPA), were measured using accelerometers. Sleep patterns were assessed through questionnaires, and BFP was determined by bioelectrical impedance analysis (BIA). The study employed compositional data analysis (CoDA) and ISM to estimate the impact of reallocating durations of different activity behaviors on BFP. RESULTS: Higher BFP was found in urban vs. rural children, decreasing with age. Overweight and obesity rates were 10.6% and 7.6%, respectively, above national averages. MVPA and LPA were negatively correlated with BFP, while SB was positively correlated. A 30-min MVPA reduction significantly increased zBFR, particularly in overweight children. Gender-specific nuances revealed that boys' MVPA negatively influenced zBFP (ß = -0.155), P < 0.05), while girls' SB positively impacted zBFP (ß = 0.636, P < 0.01). Isotemporal simulations emphasized amplified effects in overweight children, with boys' zBFR rising rapidly when MVPA was substituted and girls displaying a notable substitution effect between SB and LPA. CONCLUSION: BFP is closely linked to 24-h activity behaviors, notably in overweight and obese preschoolers. ISM identified MVPA as a critical influencer, with a 30-min reduction substantially increasing BFP. Gender disparities were evident, implicating MVPA in boys and LPA and SB in girls.
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Ejercicio Físico , Sobrepeso , Masculino , Femenino , Humanos , Preescolar , Estudios Transversales , Ejercicio Físico/fisiología , Obesidad , Tejido Adiposo , AcelerometríaRESUMEN
Objective: Based on the decision tree model, to explore the key influencing factors of children's physical fitness, rank the key influencing factors, and explain the complex interaction between the influencing factors. Methods: A cohort study design was adopted. 1,276 children (ages 3-6) from 23 kindergartens in Nanchang, China, were chosen for the study to measure the children's physical fitness at baseline and a year later and to compare the physical fitness scores at the two stages. The study was conducted following the Chinese National Physical Fitness Testing Standard (Children Part); To identify the primary influencing factors of changes in physical fitness, a decision tree model was developed, and a questionnaire survey on birth information, feeding patterns, SB, PA, dietary nutrition, sleep, parental factors, and other relevant information was conducted. Results: The levels of physical fitness indicators among preschool children showed a significant increase after 1 year. The accuracy of the CHAID model is 84.17%. It showed that 7 variables were strongly correlated with the physical changes of children's fitness, the order of importance of each variable was weekend PA, weekend MVPA, mother's BMI, mother's sports frequency, father's education, mother's education, and school day PA. Three factors are related to PA. Four factors are related to parental circumstances. In addition to the seven important variables mentioned, variables such as breakfast frequency on school day, puffed food, frequency of outing, school day MVPA, parental feeling of sports, father's occupation, and weekend breakfast frequency are all statistically significant leaf node variables. Conclusion: PA, especially weekend PA, is the most critical factor in children's physical fitness improvement and the weekend MVPA should be increased to more than 30 min/d based on the improvement of weekend PA. In addition, parental factors and school day PA are also important in making decisions about changes in fitness for children. The mother's efforts to maintain a healthy BMI and engage in regular physical activity are crucial for enhancing the physical fitness of children. Additionally, other parental factors, such as the parents' educational levels and the father's occupation, can indirectly impact the level of physical fitness in children.
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Ejercicio Físico , Padres , Humanos , Preescolar , Estudios de Cohortes , Aptitud Física , Árboles de DecisiónRESUMEN
Objective@#Based on physical activity (PA) and sedentary behavior (SB) variables on weekdays and weekends, the study aims to cluster the physical activities inside and outside kindergartens and to explore the cluster characteristics of different children using physical fitness indicators, so as to provide new strategies and methods for early childhood education and health.@*Methods@#From March to June 2019, 291 children aged 3-6 years from 6 kindergartens in Nanchang were recruited by a stratified cluster random sampling method. The ActiGraph GT3X-BT triaxial accelerometer was used to measure and analyze the PA and SB levels inside and outside the kindergarten. A twostep clustering algorithm model was employed for cluster analysis. Physical fitness were measured and evaluated according to the "National Physical Fitness Measurement Standard Manual (Preschool Section)". Differences in physical fitness among different clusters of children were compared, and the cluster characteristics of different children were analyzed.@*Results@#The clustering algorithm model indicated that based on six indicators, including PA and SB inside the kindergarten on weekdays, and PA and SB outside the kindergarten on both weekdays and weekends, children could be divided into three categories:active inside (high PA, low SB inside), active outside (high PA outside), and inactive (low PA, high SB both inside and outside). The average silhouette coefficient of the model was 0.3, indicating good clustering results. Both the active inside and active outside children showed significantly higher PA inside on weekdays, PA outside on weekdays and weekends, daily low intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) than the inactive children ( F=157.91, 80.79 , 95.86, 95.52, 124.74, P <0.05). After adjusting for gender and age, the physical fitness scores of both active outside ( 19.03 ±0.47) and active inside (19.11±0.40) were significantly higher than those of the inactive children (17.94±0.31). Additionally, active inside children (3.91±0.14) also showed significantly better performance in continuous double-leg jumps, compared to inactive children (3.45±0.11) ( P <0.05).@*Conclusion@#Children active inside and those active outside perform well in PA. Future research should focus on the proportion of structured and unstructured PA time to enhance the overall physical fitness of children.
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OBJECTIVE: To evaluate the best option among traditional Chinese exercises for reducing oxidative stress in middle-aged and older adults, using a network meta-analysis. METHODS: PubMed, Web of Science, and CNKI databases were used. We searched randomized controlled trials (RCTs) on middle-aged and older adults to influence oxidative stress by any traditional Chinese exercises from the beginning to 20 January 2022. A network meta-analysis of randomized control trials was performed comparing the changes in the concentration of glutathione peroxidase (GPX), malondialdehyde (MDA), and superoxide dismutase (SOD) as primary outcomes, following different therapeutic interventions with traditional Chinese exercises in middle-aged and older adults over 30 years old. Standardized mean differences (SMD) and 95% confidence intervals (CI) were used to assess the correlation between each group of interventions, and surface under the cumulative ranking (SUCRA) was used to rank the best interventions. RESULTS: The meta-analysis comprised 15 trials with a total of 927 participants and six interventions: (Wuqinxi (WQX), Baduanjin (BDJ), Tai Ji Quan (TJQ), Yijinjing (YJJ), Mawangdui Daoyin (MWD), and no exercise intervention (NEI)). Regarding GPX: WQX [SMD = 2.79 (1.75, 3.83)], TJQ [SMD = 0.47 (0.23, 0.70)], YJJ [SMD = 1.78 (1.18, 2.37)], MWD [SMD = 1.89 (1.36, 2.43)] were superior in increasing GPX relative to NEI. Regarding MDA: WQX [SMD = 1.68 (0.94, 2.42)], YJJ [SMD = 0.99 (0.28, 1.69)] were superior in reducing MDA relative to NEI. Regarding SOD: WQX [SMD = 1.05 (0.10, 2.01)] were superior in increasing SOD relative to NEI. WQX topped the SUCRA with GPX: 0.97, MDA: 0.91, and SOD: 0.94. Furthermore, WQX was more effective than TJQ in interfering with GPX [SMD = 2.32 (1.26, 3.39)] and MDA [SMD = 1.47 (0.26, 2.67)], and a significantly better intervention effect on SOD than YJJ [SMD = 1.52 (0.80, 2.24)] and MWD [SMD = 0.89 (0.03, 1.75)]. CONCLUSION: Traditional Chinese exercise can help middle-aged and older adults reduce oxidative stress. WQX may be the best traditional Chinese exercise of the exercises evaluated for reducing oxidative stress in middle-aged and older adults.
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Ejercicio Físico , Estrés Oxidativo , Adulto , Anciano , China , Glutatión Peroxidasa , Humanos , Persona de Mediana Edad , Metaanálisis en Red , Superóxido DismutasaRESUMEN
Introduction: To use a quantitative approach to examine the effects of family interventions on physical activity (PA) and sedentary behavior (SB) in children aged 2. 5-12 years. Methods: PubMed, OVID, Web of Science, and others were searched from their inception to May 2020. Intervention studies that examined the effects of family interventions on PA among children aged 2.5-12 years were included in this meta-analysis. Lastly, subgroup analyses were conducted to examine the potential modifying effects of family intervention's characteristics and study quality. Results: Eleven articles met the inclusion criteria for this review. Studies investigated a range of PA outcomes, including moderate-to-vigorous PA (MVPA), total PA (TPA), daily steps, and SB levels. Meta-analysis showed that family intervention had a significant effect on PA [standardized mean difference (SMD) = 0.10; 95% CI = 0.01-0.19], especially for daily steps [weight means difference (WMD) = 1,006; 95% CI = 209-1,803], but not for SB (WMD = -0.38; 95% CI = -7.21-6.46). Subgroup analyses indicated the improvements in PA occurred when children were 6-12 years old, intervention focused on PA only, intervention duration ≤ 10 weeks, and "low risk of bias" study performed. Conclusions: Family intervention may be a promising way to promote children's PA levels, especially for daily steps. Trial Registration: Meta-analysis protocol was registered on PROSPERO: CRD42020193667.
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BACKGROUND: About 70% of children and adolescents worldwide do not meet the recommended level of physical activity (PA), which is closely associated with physical, psychological, and cognitive well-being. Nowadays, the use of technologies to change PA is of interest due to the need for novel, more effective intervention approaches. The previous meta-analyses have examined smartphone-based interventions and their impact on PA in adults, but evidence in children and adolescents still needs further research. OBJECTIVE: This systematic review and meta-analysis aimed to determine the effectiveness of smartphone-based interventions for improving PA in children and adolescents. METHODS: Five electronic databases (PubMed, Web of Science, OVID, Scopus, and the China National Knowledge Infrastructure) were searched up to June 29, 2020. Randomized controlled trials with a control group that examine the effect of smartphone interventions on PA among children and adolescents were included. Bias risks were assessed using the Cochrane collaboration tool. Meta-analysis was performed to assess the pooled effect on PA using a random effects model. Subgroup analyses were conducted to examine the potential modifying effects of different factors (eg, types of intervention, intervention duration, age, measurement, study quality). RESULTS: A total of 9 studies were included in this review, including 4 mobile app interventions, 3 SMS text messaging interventions, and 2 app + SMS text messaging interventions. In general, the risk of bias of included studies was low. Compared with the control group, the use of smartphone intervention significantly improved PA (standardized mean difference [SMD] 0.44, 95% CI 0.11-0.77, P=.009), especially for total PA (TPA; weighted mean difference [WMD] 32.35, 95% CI 10.36-54.33, P=.004) and daily steps (WMD 1185, 95% CI 303-2068, P=.008), but not for moderate-to-vigorous PA (WMD 3.91, 95% CI -1.99 to 9.81, P=.19). High statistical heterogeneity was detected (I2=73.9%, P<.001) for PA. Meta-regression showed that duration (ß=-.08, 95% CI -0.15 to -0.01, n=16) was a potential factor for high heterogeneity. The results of subgroup analyses indicated that app intervention (SMD 0.76, 95% CI 0.23-1.30, P=.005), children (SMD 0.64, 95% CI 0.10-1.18, P=.02), "≤8 weeks" (SMD 0.76, 95% CI 0.23-1.30, P=.005), objective measurement (SMD 0.50, 95% CI 0.09-0.91, P=.02), and low risk of bias (SMD 0.96, 95% CI 0.38-1.54, P=.001) can significantly improve PA. CONCLUSIONS: The evidence of meta-analysis shows that smartphone-based intervention may be a promising strategy to increase TPA and steps in children and adolescents. Currently, app intervention may be a more effective strategy among smartphone intervention technologies. To extend the promise of smartphone intervention, the future needs to design comparative trials among different smartphone technologies. TRIAL REGISTRATION: PROSPERO CRD42019148261; https://tinyurl.com/y5modsrd.
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Ejercicio Físico , Teléfono Inteligente , Adolescente , Adulto , Niño , China , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Objective@#To understand the present situation of physical activity and its influencing factors, and to provide a reference for improving the level of physical activity and making the intervention measures.@*Methods@#The method of random stratification was used to select 4 740 pre school children aged 3-6 from 17 kindergartens in 12 counties and districts of Nanchang City, The questionnaire of physical activities of young children and the questionnaire of parents of physical activities of young children were applied to conduct a survey.@*Results@#Compared with weekday PA and MVPA, preschool children’s weekends decreased, SB increased. The differences in PA, MVPA and SB on weekdays and weekends were statistically significant( P <0.01). The proportion of PA and MVPA reaching the recommended amount during the working day of preschool children were 44.9%-59.2%, 45.4%- 61.7%.The proportion reaching the recommended amount of PA and MVPA on weekends were 24.7%-27.8%, 24.5%-29.9%, and the proportion reaching the recommended amount on weekdays was higher than that on weekends.@*Conclusion@#There is still gap between actual amount of physical activity and the recommended amount. There are different modes of activity on weekdays and weekends, and weekends are the least active periods. Parents and teachers should pay enough attention to the establishment of "social campus family" model to improve the lack of physical activity of preschool children.
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OBJECTIVE: Engaging in physical activity (PA) plays an important role in promoting physical and mental health, but the PA data for Chinese preschool children are lacking. This study aims to objectively assess the PA levels of preschool children in Shanghai, China and to evaluate their PA levels relative to age-specific recommendations. DESIGN, SETTING AND PARTICIPANTS: A cross-sectional study was conducted among preschool children in Shanghai, city of China. There were a total of 303 preschool children (boys, 174; girls, 129) recruited from eight kindergarten classes in the Yangpu and Baoshan Districts of Shanghai. MAIN OUTCOME MEASURES: Daily PA was assessed using ActiGraph GT3X+ accelerometers for seven consecutive days. Children were required to have data from at least 2 weekdays and 1 weekend day, with a minimum daily wear time of 480 min to be included in the analysis. RESULTS: Preschool children in Shanghai accumulated, on average, 70.9 min of moderate-to-vigorous PA (MVPA) and 168.0 min of total PA (TPA) per day (d). Boys engaged in more MVPA and TPA than girls (72.8 min/day vs 68.3 min/day and 171.9 min/day vs 162.9 min/day, respectively). Overall, 72.9% of the participants met the age-specific recommendations of MVPA, while 35.3% met TPA recommendations. CONCLUSIONS: Findings of this study warn of the insufficiency of PA in Shanghai preschool children, suggesting there is substantial room to improve their PA. TRIAL REGISTRATION NUMBER: ChiCTR-OOC-15007439; Results.
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Ejercicio Físico , Aptitud Física , Acelerometría , Índice de Masa Corporal , Niño , Preescolar , China , Estudios Transversales , Femenino , Humanos , Masculino , Factores SexualesRESUMEN
OBJECTIVE: The purpose of this study was to evaluate the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cardiovascular disease (CVD) risk factors in adults with overweight and obesity. METHODS: Twenty-two articles were included by searching six databases, the total number of subjects was 620 in these articles. Outcomes were synthesised using a random-effects meta-analysis of the Standardized mean difference (SMD) in CVD risk factors. RESULTS: HIIT and MICT resulted in statistically significant reductions in Weight, BMI, fat%, total cholesterol(TC), and improvement in VO2max. Compared with MICT, subgroup of durations of HIIT training interval ≥2 min can significantly increase VO2max (SMD = 0.444, 95% CI:0.037~0.851,P = 0.032), subgroup of energy expenditure of HIIT equal to MICT can significantly increase VO2max (SMD = 0.399, 95% CI:0.106~0.692,P = 0.008). CONCLUSIONS: HIIT appears to provide similar benefits to MICT for improving body composition, VO2maxand TC, but HIIT spent less time than MICT by 9.7 min on one session. HIIT is superior to MICT in improving cardiopulmonary fitness when durations of HIIT training interval ≥2 min or energy expenditure of HIIT same as MICT. PROSPERO ID: CRD42016045835.
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Enfermedades Cardiovasculares/prevención & control , Entrenamiento de Intervalos de Alta Intensidad/métodos , Obesidad/terapia , Sobrepeso/terapia , Acondicionamiento Físico Humano/métodos , Femenino , Humanos , Masculino , Factores de RiesgoRESUMEN
Early childhood is a critical period for development of cognitive function, but research on the association between physical activity and cognitive function in preschool children is limited and inconclusive. This study aimed to examine the association between technology-assessed physical activity and cognitive function in preschool children. A cross-sectional analysis of baseline data from the Physical Activity and Cognitive Development Study was conducted in Shanghai, China. Physical activity was measured with accelerometers for 7 consecutive days, and cognitive functions were assessed using the Chinese version of Wechsler Young Children Scale of Intelligence (C-WYCSI). Linear regression analyses were used to assess the association between physical activity and cognitive function. A total of 260 preschool children (boys, 144; girls, 116; mean age: 57.2 ± 5.4 months) were included in analyses for this study. After adjusting for confounding factors, we found that Verbal Intelligence Quotient, Performance Intelligence Quotient, and Full Intelligence Quotient were significantly correlated with light physical activity, not moderate to vigorous physical activity, in boys. Standardized coefficients were 0.211, 0.218, and 0.242 (all p < 0.05) in three different models, respectively. However, the correlation between physical activity and cognitive functions were not significant in girls (p > 0.05). These findings suggest that cognitive function is apparently associated with light physical activity in boys. Further studies are required to clarify the sex-specific effect on physical activity and cognitive functions.
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The aim of the study is to investigate the relationship between physical activity as assessed by accelerometers and cognitive development across the human age ranges (from children and adolescents to adults). Additionally, this study seeks to explore whether physical activity contributes to cognitive development via modification of plasma insulin-like growth factor 1 (IGF-1) and brain-derived neurotrophic factor (BDNF). In the study, 500 preschool children (3.5-5.5 years old) are taking part in 6 triennial assessment waves over the span of 15 years. At each wave, participant measures included (a) 7-day physical activity monitoring using ActiGraph's GT3X accelerometers, (b) the evaluation of cognitive development, (c) anthropometric and physical fitness assessments, (d) plasma IGF-1 and BDNF concentrations, and (e) retrospective questionnaires. Linear regression models are used to examine the effect of physical activity on cognitive development; plasma IGF-1 and BDNF concentrations are considered as mediators into data analyses. The results of the study may help to inform future health interventions that utilize physical activity as a means to improve cognitive development in children, adolescents, and adults. Additionally, the study may assist in determining whether the putative effects occur via modification of plasma IGF-1 or BDNF concentrations.
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Factor Neurotrófico Derivado del Encéfalo/sangre , Cognición , Ejercicio Físico , Factor I del Crecimiento Similar a la Insulina/genética , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Aptitud Física , Estudios Retrospectivos , Encuestas y CuestionariosRESUMEN
PURPOSE: To evaluate the relationships between objectively measured physical activity and physical fitness among preschool children. METHODS: A total of 346 participants (201 boys and 145 girls) aged 3.5-5.5 years (M = 4.5 yr, SD = 0.47) from Shanghai, China, completed physical fitness assessments, including triceps skinfold thickness (TSFT), grip strength, tennis throwing, sit and reach test, standing long jump, balance beam, 10mSRT, and 20mSRT. Physical activity was objectively measured by ActiGraphGT3X+ accelerometer. Multiple linear regression models were used to explore the cross-sectional associations between PA and physical fitness after adjusting for age, gender, BMI, and valid wearing time. RESULTS: Positive associations were observed between stand long jump (p < .01), tennis throwing (p < .01), laps in 20mSRT (p < .01), and MVPA. However, TSFT (p < .05), time in 10mSRT (p < .01), and balance beam (p < .05) were negatively associated with MVPA. Furthermore, positive associations were found between stand long jump (p < .01), tennis throwing (p < .01), and MVPA only in boys. Negative associations were found between time on balance beam (p < .01) and MVPA only in girls. CONCLUSIONS: MVPA appears to be an effective and reliable predictor of preschoolers' physical fitness. Boys' body composition, muscular strength, explosive strength, agility, aerobic fitness, girls' agility, aerobic fitness, and balance could improve as MVPA increases.
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Ejercicio Físico/fisiología , Aptitud Física/fisiología , Preescolar , China/epidemiología , Estudios Transversales , Femenino , Humanos , Modelos Lineales , Masculino , Factores SexualesRESUMEN
This study investigated the effect of restricting nasal breathing during a series of 20-m shuttle runs. Ten male participants (mean age = 21.7 ± 2.4 years, height = 1.80 ± 0.62 m, mass = 79.2 ± 10.4 kg, sum of 4 skinfolds = 54.5 ± 7.8 mm) were required to either (a) dive on the ground and complete a rolling sequence (condition = GRD) or (b) complete the shuttles while staying on their feet and tagging the line with 1 foot, at the end of each 20-m segment (condition = STD). The shuttle runs were completed with and without a nose clip (no clip = nc; with a clip = clip) under 4 different trial conditions in a randomized order (GRDnc; GRDclip; STDnc; and STDclip), requiring the participants to return on 4 separate occasions separated by 5-7 days. Heart rate was recorded throughout each trial, and the rate of perceived exertion (RPE) was measured at the completion of each shuttle sequence. Pretrial and posttrial lactate and respiratory function measures were also recorded. The general linear model with repeated measures analysis indicated that there was a significant effect for Roll (GRD > STD) (p ≤ 0.05) but not for Clip (p > 0.05) on total time to completion in the trials. There was no significant interaction of the conditions (Roll × Clip) for RPE (p > 0.05). Similarly, there was no significant effect for blood lactate measured 3 minutes post the last shuttle for Roll (p > 0.05) and Clip (p > 0.05). There was a significant main effect on the HR across all 6 time points (i.e., pre, intervals 1-4 and 10 minutes post) (p ≤ 0.05) and for Roll (GRD > STD) (p ≤ 0.05), but not for Clip (p > 0.05). No significant effect of Roll or Clip was found for any of the recorded ventilation measures (p > 0.05). On the basis of these findings, the use of restricted nasal breathing, while performing a high-intensity shuttle sequence as a method of increasing the acute training effect on athletes, is questionable, so strength and conditioning coaches should carefully consider their rationale for using such a training strategy.
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Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Lactatos/sangre , Respiración por la Boca , Esfuerzo Físico/fisiología , Carrera/fisiología , Aceleración , Atletas , Metabolismo Energético/fisiología , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Consumo de Oxígeno/fisiología , Valores de Referencia , Muestreo , Volumen de Ventilación Pulmonar , Atletismo , Capacidad Vital , Adulto JovenRESUMEN
Type 1 (TI) and Type 2 (T2) lymphocytes promote cell-mediated immunity and humoral immunity respectively. Evidence accumulated over the past two decades has demonstrated diverse responses of T1 and T2 cells to acute exercise or long-term training at moderate and high intensities. This brief review highlights the current findings from animal and human experimental models on the relationship between the T1 and T2 cell counts and the cytokines these cells produce, in response to moderate and high intensity exercise. The potential of using the T1/T2 balance as an indicator of immune function changes in response to exercise is discussed.
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Ejercicio Físico/fisiología , Células TH1/inmunología , Células Th2/inmunología , Factores de Edad , Animales , Biomarcadores/sangre , Humanos , Inmunidad Celular/fisiología , Inmunidad Humoral/fisiología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-4/inmunología , Interleucina-4/metabolismo , Ratones , Resistencia Física/fisiología , Células TH1/metabolismo , Células Th2/metabolismo , Factores de TiempoRESUMEN
OBJECTIVE: To observe the effect of acupuncture of "Zusanli" (ST 36) on immune function in progressively exhausted swimming rats so as to reveal its mechanism underlying improvement of strenuous exercise. METHODS: Thirty-two SD rats were randomly allocated into control group, strenuous exercise (model) group, acupuncture-Xuehai (SP 10) group, Acupuncture-Zusanli (ST 36) group (n = 8/group). The rats were forced to have a swimming in a water tank for 15-90 min in the first 8 days (once daily), then, a progressively exhausted load swimming 1 - 3 times everyday from day 9 to 13. Bilateral SP 10 and ST 36 were punctured with filiform needles and stimulated with uniform reinforcing and reducing manipulation, once daily, after termination of the swimming and for 13 days. Serum interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) contents were assayed by using enzyme linked immunosorbent assay. The rat's body weight and the spleen weight were weighted by using an electronic balance for calculating the spleen index (spleen weight /body weight x 100%) after killing the rat under deep anesthesia. RESULTS: Compared with the model group, the time of swimming-induced exhaustion appearing at the first time from day 9 to day 13 in the SP 10 and ST 36 groups was apparently lengthened (P < 0.01). No significant difference was found between SP 10 and ST 36 groups in the time of swimming-induced exhaustion appearing at the first time of the forced swimming. Compared with the control group, the spleen index, serum IFN-gamma contents and IFN-gamma/IL-4 in the model group were decreased significantly (P < 0.01, P < 0.05). In comparison with the model group, the serum IL-4 contents in the SP 10 and ST 36 groups were decreased markedly (P < 0.05, P < 0.01), and serum IFN-gamma content and IFN-gamma/IL-4 in the ST 36 group were increased significantly (P < 0.05, P < 0.01). The IFN-gamma level was significantly higher in the ST 36 group than in the SP 10 group (P < 0.05). No significant differences were found between SP 10 and ST 36 groups in the spleen index, IL-4 and IFN-gamma/IL-4 (P > 0.05). CONCLUSION: Acupuncture at "Zusanli" (ST 36) can lengthen the time of forced swimming-induced exhaustion, and upregulate serum IFN-gamma content and IFN-gamma/IL-4 in exhausted swimming rats, which may contribute to its effect in correcting Th1/Th2 imbalance after strenuous exercise. The effect of acupuncture of ST 36 is superior to that of acupuncture of SP 10.