Effects of different exercise levels on serum trace element concentrations

The present study aims to evaluate the effect of training levels on serum concentrations of trace elements including zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), and selenium (Se). Three groups of male participants at different levels of physical exercise were involved in the survey, such as professional middle- and long-distance runners (n = 20), amateur (n = 22), and sedentary subjects (n = 25). The determination of trace elements was carried out by the kinetic energy discrimination (KED) collision mode of inductively coupled plasma mass spectrometry (ICP-MS) with minimal sample consumption. It was found that there were significant differences in the concentration of Zn, Fe, Cu (all, P < 0.001) and Se (P < 0.05) between the professional group and the sedentary subjects. Mn concentration in the amateur and professional group was significantly higher than that in sedentary subjects (P < 0.001), and inversely, the concentrations of Zn (P < 0.01), Fe (P < 0.05) and Cu (P < 0.05) in the professional group were significantly lower than that in amateur. The correlations analysis demonstrated that changes in trace elements were significantly correlated with training levels: Zn (r = - 0.589, P < 0.001), Fe (- 0.469, P < 0.001), Cu (- 0.442, P < 0.001) and Se (- 0.313, 0.01) presented significant negative correlations with the degree of training, while Mn (0.674, P < 0.001) revealed a positive correlation with the degree of exercise. In addition, the professional group demonstrated that the malondialdehyde (MDA) levels (P < 0.001) and Cu/Zn ratio (P < 0.05) increased significantly under high-intensity training.