Loss of Trace Elements not a Concern in Well-Hydrated Athletes

If you are a hard-training athlete you need more than "trace amounts" of trace elements, don't you? No, actually not. You may be somewhat disappointed now, but the expensive trace element supplement you just ordered might turn out to be a complete waste of money - at least, this is what the results of a recently published study by Carlos González-Haro et al. (González-Haro. 2010) suggest.

Figure 1: Changes in plasma trace element levels (Zn, Mn, Se and Co) for the different relative exercise intensities studied and the 7 min recovery period.

As figure 1 (above) shows, lactate concentrations constantly increased in the course of the 7 minutes after a cycloergometer test, where, after a warm-up of 10 min at 2.0 W kg⁻¹, workload had been increased by 0.5 W kg⁻¹ every 10 min until exhaustion. The trace mineral concentration, on the other hand, remained stable over the whole study period (exercise + recovery). This observation led the scientists to conclude ...

[...] in euhydrated well-trained endurance athletes no effects on plasma levels of Zn, Se, Mn and Co were observed either during medium duration exercise, at a full range of intensities (41–92%VO_2peak), or during a seven-minute recovery period. These subjects showed no deficiency in Zn or Se and probably were not deficient in Mn or Co either (though cutoff levels are not known).

So, if you have not opened your "high quality trace element" supplement yet, make use of your 14-days conversion right ;-)

Zinc Supplementation Works Within Days

Zinc is probably among the most popular bodybuilding and fitness supplements on the market. Thus, it may interest you that a recent study by Wessels et al. (Wessels. 2010) found that taking supplemental zinc will increase serum zinc levels within 5 days:

We conducted a randomized, double-blind, placebo-controlled trial in 58 apparently healthy males aged 19–54 y. Participants received 1 of 3 liquid supplements daily for 21 d: 10 or 20 mg Zn/d, as Zn sulfate, or placebo. Fasting plasma Zn concentrations were measured on 14 occasions before, during, and after supplementation. [...] Controlling for baseline concentrations, plasma Zn concentrations were consistently elevated above baseline by d 5 among individuals in both of the Zn-supplemented groups compared with those receiving placebo supplements, regardless of their initial plasma Zn concentration. There were no significant group-wise differences between those who received either 10 or 20 mg/d Zn. Plasma Zn concentrations of supplemented individuals declined following withdrawal of supplementation and within 2 wk no longer differed from those of the placebo group.

What is particular interesting is that there was no difference in zinc levels regardless of the amount of zinc the subjects received. Here, we obviously have another instance of "more ain't more" and "more certainly ain't better" - the latter goes hand in hand with information on the interference of zinc supplementation with copper and iron metabolism which previously reported on the SuppVersity.