2024/11/27 by Hannah Lithgow, Laura F. Gibson, Russell B. Wilson +4 · 1 voice
Immunology and Microbiology · Medicine · #Exercise and Physiological Responses #Immune Cell Function and Interaction #T-cell and B-cell Immunology
paper · pdf · doi:10.1007/s00421-024-05677-y
openalex publication_date 2024/11/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Abstract Purpose Exercise is known to acutely affect T-lymphocyte populations in the peripheral blood, which is intensity- and duration-dependent. However, effects of longer duration endurance exercise (>5 h) on T-cells in the days following are unknown. The aim of this study was to investigate the circulating T-cell changes that occur in response to an ultra-endurance event, which may provide insight into the inflammatory response to ultra-endurance exercise. Methods Ten individuals (m = 7, f = 3) completing an Ironman 70.3 event volunteered for the study. Peripheral blood samples were taken 1–2 days pre-race (PRE-RACE), and 1 day (RACE + 1) and 2 days (RACE + 2) post-race, with circulating T-cells enumerated by flow cytometry (total CD3+, CD4+ and CD8+ T-cells, regulatory T-cells [CD4+CD25+CD127−; T REG ], naïve [CD27+CD45RA+; NA], central memory [CD27+CD45RA−; CM], effector memory [CD27−CD45RA−; EM], and effector memory CD45RA+ [CD27−CD45RA+; EMRA]). Results There were no changes in total CD3+, CD4+ and CD8+ T-cells. T REG RACE + 1 was significantly higher compared to PRE-RACE, as were the proportion of CD4+ NA cells and CD8+ CM cells at RACE + 2; CD8+ EM cells fell at RACE + 2 (absolute counts and proportion). Conclusion In conclusion, the ultra-endurance event evoked T-cell changes over the 48 h recovery period, with an increase in T-cells that regulate the immune response, and a reduction in circulating EM T-cells, most likely trafficked to sites of tissue damage and inflammation.