Red blood cell mechanical and redox resilience during post-exercise recovery in male basketball players: a pilot study

Abstract Background Red blood cells (RBC) deformability is a key determinant of microvascular perfusion, oxygen delivery, and whole blood rheology, particularly during exercise, when RBC are exposed to oxidative stress that may compromise deformability and membrane integrity. Despite this, the temporal coupling of these adaptations during recovery remains unexplored, particularly in team sport athletes. Here, we investigated time-dependent changes in RBC mechanical and oxidative properties during a 48 h recovery period in national-level basketball players compared to sedentary controls. Methods Ten male basketball players and ten age-matched sedentary controls were enrolled. Mechanical and redox properties of RBC were characterized using ektacytometry, osmotic fragility test, flow cytometry, and ABTS•⁺ radical scavenging assay. Sedentary controls were measured at rest, whereas athletes were assessed post-training (0 h), and at 24 h and 48 h of recovery. Results Maximal elongation index (EI max ) showed a non-significant trend toward group differences ( p = 0.050), with the highest values at 0 h. Osmotic fragility (H 50 ) was significantly lower at 0 and 24 h versus controls, returning to control levels by 48 h. RBC autofluorescence showed a significant group × treatment interaction: baseline autofluorescence did not differ between groups, but the increase induced by an ex vivo oxidative (TBHP) challenge was progressively smaller from controls through 0, 24, and 48 h. Total antioxidant capacity was significantly elevated at 24 and 48 h versus controls and 0 h. A significant inverse correlation between EI max and autofluorescence was found at 24 h. Conclusions RBC deformability was maintained and osmotic stability enhanced during the 48 h post-exercise recovery period, with the most pronounced changes observed at 0–24 h, while antioxidant capacity increased later, at 24–48 h. An ex vivo oxidative challenge further supported the resilience of RBC redox responses, consistent with a coordinated, time-dependent recovery pattern in trained athletes.