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Iron plays a significant role in the body, and is specifically important to athletes, since it is a dominant feature in processes such as oxygen transport and energy metabolism. Despite its importance, athlete populations, especially females and endurance athletes, are commonly diagnosed with iron deficiency, suggesting an association between sport performance and iron regulation. Although iron deficiency is most common in female athletes (~ 15-35% athlete cohorts deficient), approximately 5-11% of male athlete cohorts also present with this issue. Furthermore, interest has grown in the mechanisms that influence iron absorption in athletes over the last decade, with the link between iron regulation and exercise becoming a research focus. Specifically, exercise-induced increases in the master iron regulatory hormone, hepcidin, has been highlighted as a contributing factor towards altered iron metabolism in athletes. To date, a plethora of research has been conducted, including investigation into the impact that sex hormones, diet (e.g. macronutrient manipulation), training and environmental stress (e.g. hypoxia due to altitude training) have on an athlete's iron status, with numerous recommendations proposed for consideration. This review summarises the current state of research with respect to the aforementioned factors, drawing conclusions and recommendations for future work.

To determine the impact of altering dietary sodium intake for 3 days preceding exercise on sweat sodium concentration [NaFifteen male endurance athletes (runners n = 8, cyclists n = 7) consumed a low (LNa, 15 mg kgUNa on days 2-3 pre-exercise [mean (95% CI) LNa 16 (12-19) mg kgThree day altered sodium intake influenced urinary sodium excretion and sweat [Na

Carbohydrate ingestion prior and during exercise attenuates exercise-induced interleukin-6. This investigation examined if an analogous effect was evident for interleukin-6 and hepcidin response when carbohydrates were ingested post-exercise. In a crossover design, 11 well-trained endurance athletes completed two experimental trials. Participants completed an 8 × 3 min interval running session at 85 % vVO2peak followed by 5 h of monitored recovery. During this period, participants were provided with two 1.2 g kg−1 carbohydrate beverages at either an early feeding time (immediately post-exercise and 2 h post-exercise) or delayed feeding time (2 h post-exercise and 4 h post-exercise). Venous blood samples were collected pre-, immediately post-, 3 and 5 h post-exercise. Samples were analysed for Interleukin-6, serum iron, serum ferritin and hepcidin. Interleukin-6 was significantly elevated (p = 0.004) immediately post-exercise compared to baseline for both trials. Hepcidin levels were significantly elevated at 3 h post-exercise (p = 0.001) and 5 h post-exercise (p = 0.002) compared to baseline levels in both trials, with no significant difference between the two conditions and any time point. Serum iron was significantly increased from baseline to immediately post-exercise (p = 0.001) for both trials, with levels decreasing by 3 h (p = 0.025) and 5 h post-exercise (p = 0.001). Serum ferritin levels increased immediately post-exercise compared to baseline (p = 0.006) in both conditions. The timing and ingestion of post-exercise carbohydrate ingestion do not appear to impact post-exercise interleukin-6 and hepcidin responses; this is likely a result of the interval running task inducing an inflammatory response and subsequent up-regulation of hepcidin.

Item does not contain fulltext PURPOSE: To assess the influence of a simulated altitude exposure (~2,900 m above sea level) for a 3 h recovery period following intense interval running on post-exercise inflammation, serum iron, ferritin, erythropoietin, and hepcidin response. METHODS: In a cross-over design, ten well-trained male endurance athletes completed two 8 x 3 min interval running sessions at 85 % of their maximal aerobic velocity on a motorized treadmill, before being randomly assigned to either a hypoxic (HYP: F IO2 ~0.1513) or a normoxic (NORM: F IO2 0.2093) 3 h recovery period. Venous blood was collected pre- and immediately post-exercise, and after 3 and 24 h of recovery. Blood was analyzed for interleukin-6, serum iron, ferritin, erythropoietin, and hepcidin. RESULTS: Interleukin-6 was significantly elevated (p < 0.01) immediately post-exercise compared to baseline (NORM: 1.08 +/- 0.061 to 3.12 +/- 1.80) (HYP: 1.32 +/- 0.86 to 2.99 +/- 2.02), but was not different between conditions. Hepcidin levels were significantly elevated (p < 0.01) at 3 h post-exercise for both conditions when compared to baseline (NORM: 3.25 +/- 1.23 to 7.40 +/- 4.00) (HYP: 3.24 +/- 1.94 to 5.42 +/- 3.20), but were significantly lower (p < 0.05) in the HYP trial compared to NORM. No significant differences existed between HYP and NORM for erythropoietin, serum iron, or ferritin. CONCLUSION: Simulated altitude exposure (~2,900 m) for 3 h following intense interval running attenuates the peak hepcidin levels recorded at 3 h post-exercise. Consequently, a hypoxic recovery after exercise may be useful for athletes with compromised iron status to potentially increase acute dietary iron absorption.

To examine the effects of 24-h controlled carbohydrate intake on next day pre- and post-exercise inflammatory and hepcidin responses.In a crossover design, 12 well-trained endurance athletes (Ht 181.08 ± 7.68 cm; Wt 74.8 ± 11.5 kg, VO 2peak 68.9 ± 7.2 ml kg(-1) min(-1)) completed two experimental (2-day) trials. On day 1, participants completed a glycogen depletion task, including a 16-km run (80 % vVO 2peak) and 5 × 1 min efforts (130 % vVO 2peak) separated by 2-min recovery. Subsequently, strict dietary control was enforced for 24 h, where low carbohydrate (LCHO 3 g kg(-1)) or high carbohydrate (HCHO 10 g kg(-1)) diets were provided. Twenty-four hours later, participants completed an 8 × 3 min interval running session at 85 % vVO 2peak followed by 3-h monitored recovery. Venous blood samples were collected pre-, immediately post- and 3-h post-exercise, which were analyzed for interleukin-6, serum iron, ferritin and hepcidin.Interleukin-6 was elevated (p0.001) immediately post-exercise compared to baseline in both conditions, but was lower in HCHO (p = 0.015). Hepcidin levels were also lower at baseline (p = 0.049) in HCHO, and a large effect (d = 0.72) indicated a trend for lower levels at 3-h post-exercise compared to LCHO. Serum iron was increased post-exercise for both trials (p = 0.001), whereas serum ferritin remained unchanged.Twenty-four hours of controlled low carbohydrate intake resulted in higher baseline hepcidin levels and post-exercise IL-6 responses than a high carbohydrate intake. Such hormone increases may be induced by gluconeogenic signaling of the liver, and may negatively impact an athlete's iron metabolism.