Journal Article

Optimal timing to assess exercise‐induced oxidative stress: A systematic review and meta‐analysis

Nastos, George G., Vrabas, Ioannis S., Theodorou, Anastasios A., Fatouros, Ioannis G., Chatzinikolaou, Panagiotis N., Kyparos, Antonios, Stachteas, Chrysovalantis, Paschalis, Vassilis, Nikolaidis, Michalis G., Georgogiannis, Nikolaos, Margaritelis, Nikos V., Dinas, Petros C., Jamurtas, Athanasios Z.

2025

Overview

There is a lack of consensus on optimal timing to assess redox biomarkers post‐exercise, limiting methodological standardisation and linking oxidative stress to physiology. We determined optimal post‐exercise oxidative stress assessment times using three redox biomarkers: glutathione, F 2 ‐isoprostanes and protein carbonyls. Standardised mean differences were calculated using random‐effects models, with 95% confidence and prediction intervals. Risk of bias was assessed via RoB2 and ROBINS‐I tools. Egger's test and funnel plots evaluated publication bias. Certainty of evidence was rated using GRADE. PROSPERO preregistration: CRD42024508049. A total of 103 studies ( n  = 1418) were included. Glutathione levels decreased immediately ( g  = −0.70; 95% CI: −0.96, −0.44; P  < 0.001), at 30 min to 2 h ( g  = −0.81; 95% CI: −1.19, −0.43; P  < 0.001), and 48 h post‐exercise ( g  = −0.98; 95% CI: −1.50, −0.46; P  < 0.01). F 2 ‐isoprostanes increased immediately post‐exercise ( g  = 1.01; 95% CI: 0.70, 1.33; P  < 0.001) and at 30 min to 2 h ( g  = 0.46; 95% CI: 0.23, 0.69; P  < 0.001). Protein carbonyls increased at all time points, especially at 48 h post‐exercise ( g  = 1.17; 95% CI: 0.73, 1.60; P  < 0.001), peaking at 72 h ( g  = 1.33; 95% CI: 0.52, 2.14; P  = 0.0048). Subgroup analyses revealed that non‐muscle‐damaging exercise elicits responses immediately after exercise or within the first 2 h, while muscle‐damaging exercise induces peaks at 48 and 72 h post‐exercise. Egger's test indicated publication bias for F 2 ‐isoprostanes ( P  = 0.017) and protein carbonyls ( P  = 0.031) post‐exercise. Risk of bias was moderate in randomised controlled trials and serious in non‐randomised studies. Certainty of evidence ranged from moderate to high. In conclusion, non‐muscle‐damaging exercise elicits early responses within hours, while muscle‐damaging protocols produce delayed peaks at 48–72 h. These findings support methodological consistency and are useful for optimising study design, sample size estimation and providing links between redox biology and physiological outcomes. What is the topic of this review? The optimal timing to assess exercise‐induced oxidative stress in humans, via a systematic review and meta‐analysis of three commonly used redox biomarkers: glutathione (antioxidant), F 2 ‐isoprostanes (lipid peroxidation product) and protein carbonyls (protein oxidation product). What advances does it highlight? It delineates biomarker‐ and protocol‐specific kinetics: non‐muscle‐damaging exercise peaks immediately/within 2 h, while muscle‐damaging protocols peak at 48–72 h. It offers specimen guidance, quantifies effect sizes, grades evidence and provides practical standards for study design.

• Publisher: Wiley
• Subject: Review