Blood copper and zinc changes in runners after a marathon.

This study reports plasma and total blood cell (TBC) Cu and Zn levels of 16 runners before and after a marathon race. All the pre-race plasma values were in the normal range, while the TBC Cu level was 29.3% (P < 0.01) lower and the TBC Zn level was 29.5% (P < 0.01) higher than mean values of the control group. The run induced a significant decrease in TBC Cu concentration during the days following the race and a light increase in plasma Cu values. It caused a significant increase in TBC Zn concentration at the end of the race (followed by a decrease 24 hours later) without plasma Zn variations. These data show that intense physical exercise could modify trace-element metabolism.