The effects of coenzyme Q10 supplementation on biomarkers of exercise-induced muscle damage, physical performance, and oxidative stress: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials.

PURPOSE: This study aims to elucidate the dose-dependent effect of coenzyme Q10 supplementation (CoQ10) on exercise-induced muscle damage (EIMD), physical performance, and oxidative stress in adults. METHODS: A systematic search was conducted through PubMed, Scopus, and ISI Web of Science databases up to August 2023, focusing on randomized control trials (RCTs) that investigated the effects of CoQ10 supplementation on EIMD recovery, physical performance and oxidative stress mitigation in adults. The weighted mean difference (WMD) and 95 % confidence interval (95 %CI) were estimated using the random-effects model. RESULTS: The meta-analysis incorporated 28 RCTs, encompassing 830 subjects. CoQ10 supplementation significantly decreased creatine kinase (CK) (WMD: -50.64 IU/L; 95 %CI: -74.75, -26.53, P < 0.001), lactate dehydrogenase (LDH) (WMD: -52.10 IU/L; 95 %CI: -74.01, -30.19, P < 0.001), myoglobin (Mb) (WMD: -21.77 ng/ml; 95 %CI: -32.59, -10.94, P < 0.001), and Malondialdehyde (MDA) (WMD: -0.73 µmol/l; 95 %CI: -1.26, -0.20, P = 0.007) levels. No significant alteration in total antioxidant capacity was observed post-CoQ10 treatment. Each 100 mg/day increase in CoQ10 supplementation was correlated with a significant reduction in CK (MD: -23.07 IU/L, 95 %CI: -34.27, -11.86), LDH (WMD: -27.21 IU/L, 95 %CI: -28.23, -14.32), Mb (MD: -7.09 ng/ml; 95 %CI: -11.35, -2.83) and MDA (WMD: -0.17 µmol/l, 95 %CI: -0.29, -0.05) serum levels. Using SMD analysis, "very large" effects on LDH and "moderate" effects on CK and MDA were noted, albeit nonsignificant for other outcomes. CONCLUSION: CoQ10 supplementation may be effective in reducing biomarkers of EIMD and oxidative stress in adults. Nevertheless, given the preponderance of studies conducted in Asia, the generalizability of these findings warrants caution. Further RCTs, particularly in non-Asian populations with large sample sizes and extended supplementation durations, are essential to substantiate these observations.

Validation study of the Persian version of the subjective exercise experiences scale (SEES) in Iranian adult individuals.

BACKGROUND: Subjective exercise experiences scale (SEES) is a 12-item questionnaire assessing global psychological responses to exercise, with three constructs including positive well-Being (PWB), psychological distress (PD), and fatigue (FAT). The present study aimed to assess the reliability and validity of the SEES questionnaire in the Iranian population. METHOD: This cross-sectional psychometric study was conducted on 138 adults immediately after 30 min of walking. The internal consistency of the questionnaire was evaluated with Cronbach's alpha coefficient. To assess the test-retest reliability, 38 of the participants were requested to fill in the questionnaire again after a week. The test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). The concurrent validity was examined through the correlation matrix between the domains of SEES and SF12. Principle component analysis was performed to determine the factor loading of the measured variables. IBM SPSS statistics 24 was used for all calculations. RESULTS: Cronbach's alpha was 0.82, 0.82, and 0.81 for the PWB, PD, and FAT, respectively. The ICC value was acceptable for all subscales (ICC for PWB, PD, and FAT were 0.83, 0.88, and 0.74 respectively). There was a weak to moderate correlation between the SEES and SF-12 subclasses. Factor analysis confirmed the three-factor structure of the instrument, explaining 67.21% of the observed variance. Item 3 didn't fit in well with the three constructs and was deleted from the Persian version of the SEES. CONCLUSIONS: The Persian version of the SEES is a valid and reliable instrument to evaluate the psychological response to the exercise stimulus.