Sprint interval training (SIT) reduces serum epidermal growth factor (EGF), but not other inflammatory cytokines in trained older men

Purpose: The present study aimed to investigate the effect of age on circulating pro- and anti-inflammatory cytokines and growth factors. A secondary aim was to investigate whether a novel sprint interval training (SIT) intervention (3 x 20 s ‘all out’ static sprints, twice a week for 8 weeks) would affect inflammatory markers in older men. Methods: Nine older men (68 [1] years) and eleven younger men (28 [2] years) comprised the younger group. Aerobic fitness and inflammatory markers were taken at baseline for both groups and following the SIT intervention for the older group. Results: Interleukin (IL)-8, vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1) were unchanged for the older and younger groups at baseline (IL-8, p = 0.819; MCP-1, p = 0.248; VEGF, p = 0.264). Epidermal growth factor (EGF) was greater in the older group compared to the younger group at baseline (142 [20] pg.mL-1 and 60 [12] pg.mL-1 respectively, p = 0.001, Cohen's d = 1.64). Following SIT, older men decreased EGF to 100 (12) pg.mL-1 which was similar to that of young men who did not undergo training (p = 0.113, Cohen's d = 1.07). Conclusion: Older aerobically trained men have greater serum EGF than younger aerobically trained men. A novel SIT intervention in older men can shift circulating EGF towards trained younger concentrations. As lower EGF has previously been associated with longevity in C. elegans, the manipulative effect of SIT on EGF in healthy ageing in the human may be of further interest.