Effect of altitude training on the aerobic capacity of athletes: A systematic review and meta-analysis.

Purpose: With a growing number of athletes and coaches adopting altitude training, the importance for rationalizing and optimizing such training has been emphasized. We conducted a meta-analysis to evaluate the influence of altitude training on athletes' aerobic capacity and to explore the best altitude training method to improve this capacity. Methods: We searched Web of Science, SpringerLink, Science Direct, EBSCO, and PubMed databases combined with manual search of the references to collect studies indexed from 1979 to September 2020 on the effect of altitude training on athletes' aerobic capacity. Data from experimental studies that reported hemoglobin levels and maximum oxygen uptake in athletes before and after altitude training, or in athletes performing altitude training in comparison with a control group were analyzed. Data of the populations, intervention, comparison, outcomes and study design were extracted. Review Manager software 5.3 was used for bias evaluation. Results: 17 publications were included. In our meta-analysis, altitude training led to higher maximum oxygen uptake [standardized mean difference (SMD) = 0.67, 95% confidence interval (CI) 0.35-1.00, P < 0.001] and hemoglobin level (SMD = 0.50, 95% CI 0.11-0.90, P = 0.013) than training at lower altitude. The result of sensitivity analysis showed that results of meta-analysis were relatively stable, and there was no bias or change in the result of effect size according to the bias test. The results of subgroup analysis showed that high-altitude living and low-altitude training ("Hi-Lo" regime), with a training cycle of about three weeks at an altitude around 2500 m, had better effects than other regimes on the athletes' aerobic capacity. Conclusions: Altitude training can improve athletes' aerobic capacity in terms of maximum oxygen uptake and hemoglobin level. Our results are limited by the number and quality of available studies. Therefore, more high-quality studies are needed to verify and extend these findings. Our study can provide scientific suggestions for the training of athletes.

Effect of mindfulness meditation on depression during pregnancy: A meta-analysis.

Purpose: This study systematically evaluates the effect of mindfulness meditation on depression during pregnancy. We provide evidence-based suggestions for preventing and reducing depression during pregnancy by exploring the most effective intervention mode, cycle, and frequency of mindfulness meditation. Methods: Records were retrieved from PubMed, Web of Science, EBSCO, and Science Direct. A total of 1,612 randomized controlled trial studies on the effect of mindfulness meditation on pregnancy depression were collected. 10 studies with 658 subjects meeting the inclusion criteria were extracted and analyzed by Revman 5.3 to evaluate study qualities. Stata 12.0 was used for the meta-analysis. Results: Mindfulness meditation had a positive effect on depression during pregnancy [standardized difference of the mean (SMD) = -0.786, 95% confidence interval (-1.289, -0.283), P < 0.001]. Subgroup analysis showed that mindfulness-based cognitive therapy (MBCT) had the best intervention effect on depression during pregnancy (SMD = 2.795), the best intervention duration was below 4 weeks (SMD = 1.756), applied from the first to the third stage of pregnancy (SMD = 1.024), the frequency guided by experts was less than six times a week (SMD = 2.055) of <60 min each time (SMD = 1.068), and completing homework by themselves every day for 30 mins (SMD = 1.822) was most significant for the improvement of depression during pregnancy. We found high heterogeneity across studies [q = 97.003, DF = 10, I2 = 88.0% (P < 0.001), I2 > 75%]. This may be caused by variance in measurement tools, among which Beck Depression Inventory-II was a significant source of heterogeneity. Conclusion: Mindfulness meditation can improve the prevention, remission, and reduction of depression during pregnancy and can be used as an auxiliary measure for the clinical treatment of pregnancy depression.

A Study on the Correlation Between Undergraduate Students' Exercise Motivation, Exercise Self-Efficacy, and Exercise Behaviour Under the COVID-19 Epidemic Environment.

The outbreak of COVID-19 epidemic has influenced human beings from various aspects including physical exercise behaviours. This study aims to explore the influence of the COVID-19 epidemic on exercise self-efficacy and exercise behaviour, as well as the intermediary effects of exercise motivation. A sample of 1,115 undergraduate students was investigated using the physical exercise behaviour scale, exercise self-efficacy scale, and exercise motivation scale, combined with the COVID-19 epidemic environment as an influencing factor. SPSS was used for statistical analysis and AMOS for the prediction model building. Logical analysis was undertaken to sort out and analyse the data. The structural equation model reveals that exercise self-efficacy has a positive effect on exercise motivation and exercise behaviour. Meanwhile, the COVID-19 epidemic environment negatively influences exercise behaviour through the intermediary role of exercise self-efficacy and exercise motivation. Moreover, the intermediary effect of exercise self-efficacy is greater than that of exercise self-efficacy and exercise motivation. This study provides both theoretical implications and practical guidelines for society and undergraduate students to improve their exercise behaviour during epidemic.

Satisfaction Levels of Young Urban Residents With Public Sports Services in China During the COVID-19 Epidemic.

The extensive changes in public and private life caused by the ongoing COVID-19 epidemic in China have created a "new normal." To understand urban residents' satisfaction with public sports services under these conditions and to identify factors that influence satisfaction, urban residents in several major Chinese cities were randomly sampled with an online questionnaire to measure their level of satisfaction with public sports services in China during the COVID-19 epidemic. With the response rate of 87.9%, 703 valid questionnaires out of 800 questionnaires distributed were analyzed. A structural equation model was constructed where health literacy and the residents' expectations were independent variables, residents' participation was a mediating variable, and residents' satisfaction was the dependent variable. Cronbach's α test and Kaiser-Meyer-Olkin test confirmed that the questionnaire was reliable and valid. Survey results suggest that young urban residents' participation in public sports services is influenced by personal health literacy and residents' expectations. Participation serves a mediating role between health literacy and residents' satisfaction, but not between residents' expectations and their satisfaction. Young urban residents' satisfaction with public sports services may be improved by increasing access to health information, improving hardware and software platforms to support those services, and catering the services to the interests of the population.

The Impact of Perceptions of Positive COVID-19 Information on Travel Motivation and Intention: Evidence From Chinese University Students.

The COVID-19 pandemic has influenced the tourism industry in various ways, including tourists' travel motivations and intentions. Unlike previous studies that have focused on the dark side of the pandemic, this study adds the dimension of perceptions of positive information on COVID-19 to the Theory of Planned Behavior to explore their influence on travel motivation and intention. A total of 470 valid questionnaires were collected from a sample of Chinese university students. The results showed that the students' perceptions of positive COVID-19 information positively impacted their travel intentions through the variables of perceived behavioral control, travel attitudes, and travel motivations. Perceived behavioral control was the mediating variable that most explained the impact of perceptions of positive COVID-19 information on travel motivation and intention. This study contributes to the understanding of the influence of the COVID-19 pandemic on tourism and of university students' travel motivations and intentions. It also offers implications for the tourism industry to formulate relevant recovery strategies during and after the pandemic.