Effect of High-Intensity Exercise on Early Responses of Iron and Iron Regulatory Proteins in Young Female Basketball Players

Abstract Background Accumulation of physiological stress and the presence of inflammation disturb iron management in athletes during intense training. However, little is known about the mechanisms regulating iron levels in athletes during training periods with low training loads. In the current study, we analyzed the effect of exercise on early responses of iron and iron regulatory proteins during such training periods. Methods The study was performed at the end of competitive phase of training. Twenty-seven trained female basketball players (age, 16,55 ± 0,96 years; weight, 66,40 ± 13,68 kg) participated in the study. The participants performed a maximum exercise test on a treadmill. Blood samples were taken before the test, immediately after exercise, and after 3 h of restitution. Parameters, such as interleukin (IL) 6, hepcidin, ferritin, transferrin, hemopexin, and lactoferrin levels, and TIBC and UIBC were determined by using appropriate biochemical tests. Results Intense physical effort performed at the end of the competitive phase led to an increase in iron levels after exercise. The iron levels decreased within 3 h of exercise. No significant changes in the levels of hepcidin, IL-6, and other proteins related to the regulation of iron levels were observed. Except for iron levels, only TIBC levels significantly increased after exercise and decreased to baseline level during rest period. Conclusions The results suggest that at the end of the competitive phase of training, when training loads are much lower than those at the beginning or in the middle of competitive phase, the post-exercise increase in iron levels is not necessarily accompanied by a simultaneous increase in the levels of hepcidin or inflammatory markers. Ferritin may be the source of iron ions and transferrin may be responsible for their return to baseline. However, both the source of the released iron ions and the mechanism responsible for their regulation require further research.