Search

This cross-sectional study aimed to explore the characteristics of cellphone use in Chinese early adolescents and the moderating and mediating role of self-control in the relationships among sedentary behavior, physical exercise, and cellphone use time. Using convenience sampling, we selected eight middle schools in Guangzhou, China. Two classes in the first grade of each middle school were randomly selected as the survey subjects. A total of 715 early adolescents (ages 11–13) completed surveys about the purpose of using cellphones (i.e., learning, entertainment, and others), cellphone use scenarios (i.e., sitting, standing, and moving), sedentary behavior, physical exercise, cellphone use time, and self-control. The results showed that the mean total daily cellphone use was 36.44 ± 37.42 min/day in early adolescents, who used cellphones mainly for studying, and 91.7% of them were seated when using cellphones. Cellphone use time was positively correlated with sedentary behavior, not correlated with physical exercise, and negatively correlated with self-control. Self-control played a moderating (not mediating) role not only between sedentary behavior and cellphone use time but also between physical exercise and cellphone use time. This study revealed the complex relationships among sedentary behavior, physical exercise, self-control, and cellphone use time. Our findings have significance for preventing the overuse of cellphones among early adolescents.

This study investigated the effects of exercise and diet intervention on appetite-regulating hormones and subjective appetite changes in obese children and examined expressions of specific key microRNAs (miRNA, miR). 16 obese children were included in a training program consisting of exercise and diet intervention for 6 weeks. Before and after the intervention, fasting blood was collected to determine appetite-regulating hormones (leptin, ghrelin, and orexin) and miRNA (miR-103a-3p and miR-200a-3p) levels; eating behavior of the children was reported using the Children Eating Behavior Questionnaire (CEBQ). The level of orexin was significantly decreased (P

This study investigated smartphone use characteristics including the purpose of smartphone use (i.e., leisure, learning, or work) and situational smartphone use (i.e., sitting, standing, or moving about) in Chinese adolescents. Moreover, it tested the moderating role of self-control in the link between sedentary behavior and problematic smartphone use. A total of 947 adolescents completed measures of the purpose of their smartphone use, situational smartphone use, sedentary behavior, self-control, time on smartphone, and smartphone addiction. Results showed that the majority of smartphone use was for leisure and learning, and 90.9% of adolescents reported typically sitting as they used the smartphone. Problematic smartphone use was positively correlated with sedentary behavior and negatively correlated with self-control. Moreover, the relationship between sedentary behavior and problematic smartphone use was moderated by self-control, in that the negative correlation was stronger for adolescents with low self-control and weaker for those with high self-control. These results contribute to the understanding of when sedentary behavior is associated with problematic smartphone use. Several limitations and implications are discussed in this study.

Objectives This meta-analysis of randomized controlled trials aimed to assess the effect of neurofeedback training (NFT) on sport performance and electroencephalography (EEG) power in athletes. Method A computerized search of Web of Science, PsycINFO and PubMed was performed to identify relevant studies, published 1990 through February 1, 2017. The outcome measures were sport performance and EEG power. Two review authors identified eligible studies and extracted data independently. The quality of the included studies was assessed with the Cochrane Risk of Bias tool. Standard mean differences (SMDs) and 95% confidence intervals (CIs) were calculated and pooled using a random effects model. Results A total of 10 randomized controlled trials (229 athletes) met the inclusion criteria. Significant effects of NFT were found for sport performance (SMD = 0.65, 95%CI = 0.28 to 1.03, p = .0006) and EEG power (SMD = 0.45, 95%CI = 0.09 to 0.80, p = .01). However, the NFT's effect for sport performance was not significantly different when compared to well-controlled trials with active/placebo control (SMD = 0.51, 95% CI = −0.27 to 1.30, p = .20). Conclusions NFT could make athletes change in EEG power and effectively improve sport performance. Effect of NFT for sport performance was moderated by control group design, that is, when analyses were restricted to active/placebo controls, the efficacy NFT applied in sport performance might be rather weak. Future efforts should focus on standard NFT protocols and better-organized trials.

Objectives The aims of this study were to use functional near-infrared spectroscopy (fNIRS) to determine whether cardiovascular fitness levels modulate the activation of the mirror neuron system (MNS) under table-setting tasks in non-exercise situation, to replicate the study that positive effect of acute moderate-intensity exercise on the MNS and investigate whether cardiovascular fitness levels modulates the effect of exercise on the activation of the MNS. Methods Thirty-six healthy college-aged participants completed a maximal graded exercise test (GXT) and were categorized as high, moderate, or low cardiovascular fitness. Participants then performed table-setting tasks including an action execution task (EXEC) and action observation task (OBS) prior to (PRE) and after (POST) either a rest condition (CTRL) or a cycling exercise condition (EXP). The EXP condition consisted of a 5-min warm-up, 15-min moderate-intensity exercise (65% VO2 max), and 5-min cool-down. Results No significant differences were observed for Oxy-Hb and Deoxy-Hb between different cardiovascular fitness levels in the EXEC or OBS tasks in the non-exercise session. But there were significant improvements of oxygenated hemoglobin (Oxy-Hb) in the inferior frontal gyrus (IFG) and pre-motor area (PMC) regions under the OBS task following the acute moderate exercise. Particularly, the improvements (Post-Pre) of Δ Oxy-Hb were mainly observed in high and low fitness individuals. There was also a significant improvement of deoxygenated hemoglobin (Deoxy-Hb) in the IPL region under the OBS task. The following analysis indicated that exercise improved Δ Deoxy-Hb in high fitness individuals. Conclusion This study indicated that the activation of MNS was not modulated by the cardiovascular fitness levels in the non-exercise situation. We replicated the previous study that moderate exercise improved activation of MNS; we also provided the first empirical evidence that moderate-intensity exercise positively affects the MNS activation in college students of high and low cardiovascular fitness levels.

Objective The aim of this study was to determine whether a combined exercise and dietary intervention improved cognitive and physical self-control and whether pre-to-post interventional changes in self-control were mediated by changes in body mass index (BMI) and maximal grip strength (MGS), in a sample of obese adolescents. Methods Forty-four obese adolescents were randomly assigned to a combined exercise and dietary program or to a waitlist control group; the data from 36 participants (n = 18 for each group) were analyzed. The combined exercise and dietary program was performed over 6 weeks and was supervised by qualified trainers in a closed boot camp. The exercise consisted primarily of typical aerobic training, sports, outdoor training, yoga, and resistance training. Participants were placed on moderate dietary restriction according to individual target body weight (30 kcal/kg × target weight). The primary outcomes of this study were metrics based on cognitive and physical self-control, assessed by the Stroop task and a handgrip task, respectively. Secondary outcomes included BMI and MGS. Results The combined exercise and dietary intervention significantly improved both cognitive and physical self-control. Similar positive effects were also found for reduced BMI and enhanced MGS. Correlation analyses showed that the reduced BMI and enhanced MGS were significantly closely associated with improved cognitive and physical self-control. The mediation analyses revealed that the pre-to-post intervention changes in BMI and MGS significantly mediated physical self-control, but did not mediate cognitive self-control. Conclusion Our combined exercise and dietary intervention is an effective approach to improve multiple aspects of self-control, reduce BMI, and strengthen MGS among obese adolescents. These findings also suggest that reduced BMI and enhanced MGS mediate specific aspects of self-control.