Previous research investigating single bouts of exercise have identified baseline iron status and circulating concentrations of interleukin-6 (IL-6) as contributors to the magnitude of postexercise hepcidin increase. The current study examined the effects of repeated training bouts in close succession on IL-6 and hepcidin responses. In a randomized, crossover design, 16 elite male rowers completed two trials, a week apart, with either high (1,000 mg) or low (<50 mg) calcium pre-exercise meals. Each trial involved two, submaximal 90-min rowing ergometer sessions, 2.5 hr apart, with venous blood sampled at baseline; pre-exercise; and 0, 1, 2, and 3 hr after each session. Peak elevations in IL-6 (approximately 7.5-fold, p < .0001) and hepcidin (approximately threefold, p < .0001) concentrations relative to baseline were seen at 2 and 3 hr after the first session, respectively. Following the second session, concentrations of both IL-6 and hepcidin remained elevated above baseline, exhibiting a plateau rather than an additive increase (2 hr post first session vs. 2 hr post second session, p = 1.00). Pre-exercise calcium resulted in a slightly greater elevation in hepcidin across all time points compared with control (p = .0005); however, no effect on IL-6 was evident (p = .27). Performing multiple submaximal training sessions in close succession with adequate nutritional support does not result in an amplified increase in IL-6 or hepcidin concentrations following the second session in male elite rowers. Although effects of calcium intake require further investigation, athletes should continue to prioritize iron consumption around morning exercise prior to exercise-induced hepcidin elevations to maximize absorption.

先前调查单次运动的研究已经确定基线铁状态和白细胞介素 6 (IL-6) 的循环浓度是运动后铁调素增加幅度的贡献者。目前的研究检查了连续重复训练对 IL-6 和铁调素反应的影响。在一项随机交叉设计中，16 名精英男性赛艇运动员完成了两项试验，间隔一周，运动前摄入高钙（1,000 毫克）或低钙（<50 毫克）。每项试验包括两次次极量 90 分钟的划船测力计训练，间隔 2.5 小时，在基线采集静脉血样本；运动前；以及每次会议后的 0、1、2 和 3 小时。IL-6（约 7.5 倍，p < .0001）和铁调素（约三倍，p<.0001) 相对于基线的浓度分别出现在第一次会议后 2 小时和 3 小时。在第二次会议之后，IL-6 和 hepcidin 的浓度仍然高于基线，表现出平稳而不是累加增加（第一次会议后 2 小时与第二次会议后 2 小时，p  = 1.00）。与对照组相比，运动前补钙导致所有时间点的铁调素略微升高 ( p  = .0005)；然而，对 IL-6 没有明显影响（p = .27). 在男性精英赛艇运动员的第二次训练后，在足够的营养支持下连续进行多次次极量训练不会导致 IL-6 或铁调素浓度的增加。尽管钙摄入量的影响需要进一步研究，但运动员应继续优先考虑在运动引起的铁调素升高之前在晨练前后消耗铁，以最大限度地吸收铁。