The effect of caffeine supplementation on muscular strength and endurance: A meta-analysis of meta-analyses.

Background: Caffeine is commonly used as an ergogenic aid to increase strength and endurance in athletes. The results of meta-analyses in this regard are still conflicting. Therefore, the current umbrella meta -analysis was conducted to determine the effects of caffeine supplementation on muscle strength and endurance as a clear and final conclusion. Methods: Relevant studies were searched in international databases including PubMed, Scopus, and Web of Science until August 15, 2022. Meta-analysis studies examining the effects of caffeine supplementation on muscle strength and endurance were included in this study. Random effects model was used to perform meta-analysis. Additional analyses including subgroup and sensitivity analyzes were performed. Findings: In general, 9 meta-analyses were included in the study. The results showed that caffeine supplementation led to a significant increase in muscle strength (SMD = 0.18, 95 % CI: 0.14, 0.21; p < 0.001) and muscle endurance (SMD = 0.30, 95 % CI 0.21, 0.38; p < 0.001). Conclusion: Meta -analysis showed the significant effects of caffeine consumption on muscle strength and muscle endurance. Due to the lack of evidence, further studies are needed in the women's population.

Major Dietary Patterns, Exercise Addiction, and Eating Disorders Among a Sample of Physically Active Young Adults.

Background: Regular exercise has been widely acknowledged for its numerous health benefits, including improvements in physical fitness, body function, and mental well-being. However, excessive exercise and unhealthy dietary patterns can lead to adverse effects on individuals' physical and psychological well-being. This study aimed to examine the association of dietary patterns, exercise addiction, and eating disorders among physically active young adults. Method: In this cross-sectional study, a total of 200 physically active young adults aged 18-35 years were included. The participants' dietary intake was assessed using a validated semi-quantitative food frequency questionnaire (FFQ) consisting of 80 food items. To determine dietary patterns, factor analysis was employed. Exercise addiction was evaluated using The Exercise Addiction Inventory (EAI) and Exercise Dependence Questionnaire (EDQ), and eating disorders were assessed using The Eating Disorder Examination-Questionnaire Short (EDE-QS). Result: Three main dietary patterns were identified: western, healthy, and traditional dietary patterns. The western dietary pattern was associated with increased waist-to-hip ratio (P = .01) that remained significant after adjustment for confounders (eg, age, gender, BMI, and physical activity P = .03), while the adherence to traditional dietary pattern was linked to higher waist circumference and body shape index (P < .05). Participants that followed the healthy dietary pattern showed a higher score of EAI and body shape concern (P = .04). Furthermore, in structural equation modelling (SEM), eating disorder was identified as a significant positive predictor of exercise addiction (r = .17, P < .05). Conclusion: According to our finding, those with the higher adherence to healthy dietary pattern had higher scores of exercise addiction and body shape concern. Also, eating disorder was a potential predictor of exercise addiction among young physically active individuals. Further research and targeted interventions are needed to better understand these complex relationships and develop effective strategies to promote healthy behaviors and mitigate the risk of adverse outcomes.

Psychometric properties of the exercise addiction inventory (EAI) questionnaire among physically active young adults.

BACKGROUND: Exercise addiction (EA) is a pathological behavior pattern in which a person loses control over his exercise habits and exercises excessively and suffers negative consequences for his health and even his social life. One of the best tools to measure EA is EAI. The aim of this study was to examine the psychometric properties of the EAI among Iranian physically active young adults. METHODS: Participants were randomly selected from sports clubs in Tabriz, Iran. A total of 200 questionnaires were completed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted along with tests of convergent validity. Reliability was assessed using Cronbach's alpha and test-retest methods. RESULTS: EFA indicated a one-factor structure explaining 40.43% of variance. CFA confirmed the one-factor model with good fit (Root Mean Square Error of Approximation [RMSEA] = 0.076; Comparative Fit Index [CFI] = 0.968). Internal consistency was acceptable (Cronbach's alpha = 0.71) and convergent validity was adequate. Test-retest reliability was also adequate (intraclass correlation coefficient [ICC] = 0.71). CONCLUSION: The results of our study show that the Persian EAI has satisfactory psychometric properties and can be used as a valid tool to assess EA.

Factors associated with health-related quality of life in women using path analyses: mediation effect of the adiposity traits.

BACKGROUND: The current work aimed to investigate the mediating role of adiposity traits in the relationship between eating behaviors, sleep quality, socio-demographic factors, and the health-related quality of life in women of reproductive age in northwest of Iran. METHODS: In the current cross-sectional study, a total of 278 overweight and obese women of reproductive age (20-49 y) were enrolled. Anthropometric assessments were performed. Pittsburgh sleep quality index (PSQI) was used for assessment of sleep quality while Short Form 36 (SF-36) questionnaire was used to measure health-related quality of life (HRQoL). Three-Factor Eating Questionnaire-R18 (TFEQ-R18) was used to measure eating behaviors. Path analysis was used to test the relationships between parameters. RESULTS: Age was found to be indirectly and negatively associated with mental component score (MCS) (B = - 0.040; P = 0.049) and physical component score (PCS) (B = - 0.065; P = 0.036) through mediatory effects of obesity. Additionally, education was seen to be indirectly and positively related to MCS (B = 0.529; P = 0.045) and PCS (B = 0.870; P = 0.019), respectively. On the other hand, obesity (B = 0.608; P = 0.018) and PSQI score (B = - 0.240; P = 0.034) had direct associations with MCS. Age (B = - 0.065; P = 0.036) and education (B = 0.870; P = 0.019) were also directly associated with obesity. CONCLUSIONS: Obesity seemed to mediate the effects of socio-demographic parameters on HRQoL. Poor sleep quality was also related to impairment of HRQoL. Further studies are needed to confirm these results.