Background: The aim of the present study was to determine changes occurring in the erythrocyte concentrations of chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), selenium (Se) and zinc (Zn) in male subjects with different training levels living in the same region (Spain). Methods: Thirty sedentary subjects (24.34 ± 3.02 years) formed the control group (CG); 24 moderately trained (4-7 h/week) subjects (23.53 ± 1.85 years) formed the group with a moderate degree of training (MTG) and 22 professional cyclists (23.29 ± 2.73 years), who performed more than 20 h/week of training, formed the highlevel training group (HTG). Erythrocyte samples were collected from all subjects in fasting conditions, washed and frozen at − 80°C until analysis. Erythrocyte analysis of trace elements was performed by inductively coupled plasma mass spectrometry (ICP-MS). Results: The results showed that there was a statistically significant lower erythrocyte concentration of Cu, Mn, Mo and Zn in the MTG and HTG than CG. Se was only significantly lower in HTG than CG. The correlation analysis indicates that this change was correlated with training in the case of Cu, Mn, Se and Zn. All results are expressed in μg/g Hb. Conclusions: We can conclude that physical training produces a decrease in erythrocyte concentrations of Cu, Mn, Se and Zn, which can cause a decrement in athletes' performance given the importance of these elements. For this reason, erythrocyte monitoring during the season would seem to be advisable to avoid negative effects on performance.

The current information about the effect of physical exercise on the body concentrations of several minerals is still limited, both in the acute (short-term) and adaptive (long-term) responses. So, this manuscript aims, on the one hand, to assess the possible differences on basal levels of cobalt (Co), copper (Cu), and manganese (Mn) concentrations in serum and urine between athletes and sedentary participants and, on the other hand, to evaluate the effect of an acute progressive physical exercise until voluntary exhaustion on the serum and urinary concentrations of Co, Cu, and Mn. Two groups participated in this survey, one was formed by untrained, sedentary males (CG; n = 26), and the other group was constituted by national endurance (long and middle distances) athletes (AG; n = 21). All participants were from the same region of Spain. Participants of both groups performed a physical test on a treadmill, reaching voluntary exhaustion. Blood and urine samples of each participant were collected before and at after the tests. Once obtained and processed, the concentrations of Co, Cu, and Mn elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The differences in the studied variables were evaluated using a mixed model by means of an ANOVA and Bonferroni post hoc tests. In the comparison of the pre-test values between groups, the results showed that serum concentrations of Mn were significantly lower in CG than in AG (p < 0.01). In urine, Co and Mn levels were significantly higher among CG participants (p < 0.01) than among AG ones, while in the case of Cu, the values were lower (p < 0.01) in the CG than in the AG. Regarding the effects of the effort tests, no significant changes were found among the participants of the CG. It was observed that the serum concentrations of Co (p < 0.05) and Cu (p < 0.01) decreased after the test among the AG participants. Also, the results showed that there were no statistical differences in Co and Mn values (expressed in μg/g creatinine). However, the urinary post-test Cu concentrations were lower (p < 0.05) among AG participants. In basal conditions, serum concentrations of Mn were significantly lower in CG than in AG. In urine, Co and Mn levels were significantly higher among CG participants and Cu level was significantly lower in CG, a fact which may reflect adaptive responses to exercise. An incremental exercise to exhaustion in AG produces a decrease in Co and Cu serum concentrations, as well as in urinary excretion of Cu.

Background Physical training produces changes in the extracellular and intracellular concentrations of trace minerals elements. To our knowledge, only three compartments have been studied simultaneously. The aim of the present study was to analyze the influence of physical training on extracellular (serum, plasma and urine) and intracellular (erythrocytes and platelets) concentrations of Copper (Cu). Methods Forty young men participated in this study. The participants were divided into a training group (TG; n = 20; 18.15 ± 0.27 years; 68.59 ± 4.18 kg; 1.76 ± 0.04 m) and a control group (CG; n = 20; 19.25 ± 0.39 years; 73.45 ± 9.04 kg; 1.79 ± 0.06 m). The TG was formed by semi-professional soccer players from a youth category with a regular training plan of 10 h/week. All of them had been participating in high level competitions and had trained for at least 5 years. Plasma, serum, urine, erythrocyte and platelet samples of Cu were obtained and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Results The TG showed lower concentrations of Cu in erythrocytes (p < 0.05) despite similar intakes. There were no significant differences in Cu concentrations in plasma, serum, urine and platelets although the trend was similar to that observed in erythrocytes. Conclusions The assessment of trace element concentrations should be carried out in both extracellular and intracellular compartments to obtain a proper evaluation and to identify possible deficiencies of the element. We believe that additional Cu supplementation is needed in athletes who perform physical training regularly.

Background Physical exercise affects zinc (Zn) homeostasis. This study aimed to analyze the influence of physical training on extracellular (serum, plasma, and urine) and intracellular (erythrocytes and platelets) concentrations of Zn. Methods Forty young men, divided into a training group (TG; n = 20; 18.15 ± 0.27 years; 68.59 ± 4.18 kg; 1.76 ± 0.04 m) and a control group (CG; n = 20; 19.25 ± 0.39 years; 73.45 ± 9.04 kg; 1.79 ± 0.06 m), participated in this study. The TG was formed by semiprofessional soccer players from a youth category with a regular training plan of 10 h/week. The CG was formed by healthy men who did not practice physical exercise and had not followed any specific training plan. Plasma, serum, urine, erythrocyte, and platelet samples of Zn were obtained and analyzed by inductively coupled plasma mass spectrometry. Results The TG showed elevated plasma Zn concentrations (p < 0.01) despite similar intakes. However, TG showed reduced absolute (p < 0.01) and relative (p < 0.05) Zn concentrations in erythrocytes. Conclusions Athletes who underwent regular physical training showed elevated plasma and reduced erythrocyte Zn concentrations despite similar intakes to the CG.

Background: The present study aimed to determine changes occurring in the erythrocyte concentrations of Iron (Fe), Magnesium (Mg) and Phosphorous (P) of subjects with different levels of physical training living in the same area of Extremadura (Spain). Methods: Thirty sedentary subjects (24.34 ± 3.02 years) without sports practice and a less active lifestyle, formed the control group (CG); 24 non-professional subjects (23.53 ± 1.85 years), who perform between 4 and 6 h/week of moderate sports practice without any performance objective and without following systematic training formed the group of subjects with a moderate level of training (MTG), and 22 professional cyclists (23.29 ± 2.73 years) at the beginning of their sports season, who performed more than 20 h/week of training, formed the high-level training group (HTG). Erythrocyte samples from all subjects were collected and frozen at − 80°C until analysis. Erythrocyte analysis of Fe, Mg and P was performed by inductively coupled plasma mass spectrometry (ICP-MS). All results are expressed in μg/g Hb. Results: The results showed that there were statistically significant lower concentrations of erythrocyte Fe, Mg and P in MTG and HTG than CG. All parameters (Fe, Mg and P concentrations in erythrocytes) correlated inversely with physical training. Conclusions: Physical exercise produces a decrease in erythrocyte concentrations of Fe, Mg and P. This situation could cause alterations in the performance of athletes given the importance of these elements. For this reason, we recommend an erythrocyte control at the beginning, and during the training period, to avoid harmful deficits.