Iron Status and the Acute Post-Exercise Hepcidin Response in Athletes

Abstract

This study explored the relationship between serum ferritin and hepcidin in athletes. Baseline serum ferritin levels of 54 athletes from the control trial of five investigations conducted in our laboratory were considered; athletes were grouped according to values <30 μg/L (SF<30), 30–50 μg/L (SF30–50), 50–100 μg/L (SF50–100), or >100 μg/L (SF>100). Data pooling resulted in each athlete completing one of five running sessions: (1) 8×3 min at 85% vVO2peak; (2) 5×4 min at 90% vVO2peak; (3) 90 min continuous at 75% vVO2peak; (4) 40 min continuous at 75% vVO2peak; (5) 40 min continuous at 65% vVO2peak. Athletes from each running session were represented amongst all four groups; hence, the mean exercise duration and intensity were not different (p>0.05). Venous blood samples were collected pre-, post- and 3 h post-exercise, and were analysed for serum ferritin, iron, interleukin-6 (IL-6) and hepcidin-25. Baseline and post-exercise serum ferritin levels were different between groups (p<0.05). There were no group differences for pre- or post-exercise serum iron or IL-6 (p>0.05). Post-exercise IL-6 was significantly elevated compared to baseline within each group (p<0.05). Pre- and 3 h post-exercise hepcidin-25 was sequentially greater as the groups baseline serum ferritin levels increased (p<0.05). However, post-exercise hepcidin levels were only significantly elevated in three groups (SF30–50, SF50–100, and SF>100; p<0.05). An athlete's iron stores may dictate the baseline hepcidin levels and the magnitude of post-exercise hepcidin response. Low iron stores suppressed post-exercise hepcidin, seemingly overriding any inflammatory-driven increases.

Iron status markers are only transiently affected by a football game

“…Although more than 50% of female football players may be at risk of compromised iron stores immediately after a football-specific training session (Tan, Dawson, & Peeling, 2012), our results indicate that iron status of functionally iron-deficient male players are minimally affected by a football game and/or daily training. Similarly, prolonged cycling failed to alter Ferr concentration during the first 24 h post-exercise (Nikolaidis, Michailidis, & Mougios, 2003), whereas five consecutive running sessions increased serum iron and Ferr concentrations (Peeling et al, 2014). Nevertheless, TIBC remained elevated during recovery.…”

Interleukin-6 and Hepcidin Levels during Hormone-Deplete and Hormone-Replete Phases of an Oral Contraceptive Cycle: A Pilot Study

“…Considering that hepcidin and IL-6 were unchanged between OCC phases, this likely explains similar transferrin saturation levels in WD and AHT. Finally, recent work has also demonstrated a link between ferritin and hepcidin levels [26]. …”

“…Peeling et al [26] examined the relationship between basal serum ferritin and hepcidin levels. Serum ferritin levels of 54 individuals from the control trial of 5 investigations conducted in their laboratory were considered; participants were grouped according to serum ferritin values; <30 µg/L (SF <30), 30-50 µg/L (SF 30-50), 50-100 µg/L (SF 50-100), or >100 µg/L (SF >100).…”

Timing of post-exercise carbohydrate ingestion: influence on IL-6 and hepcidin responses

“…Volunteers who presented with food allergies (e.g. lactose intolerance, nuts, celiac disease) or compromised iron stores (serum ferritin <30 µg L −1 : see Peeling et al 2014) were excluded from participation.…”