is an essential trace element that is involved in many
cellular signaling events including those associated with proper liver function, cellular repair, and hormone maintenance. In
, zinc is very important, especially since one of its fundamental roles is to initiate protein synthesis through activating rapamycin (mTOR). As well, there is evidence that zinc helps to maintain hormone levels during times of stress. Studies show that regular weight training commonly leads to zinc deficiency, which is associated with catabolism and decreased immune function.
In a relatively recent in vivo study, it was found that mice that ingested supplemental zinc had dose dependent increases in skeletal muscle proteins linked to mTOR signaling and anabolism. Additional support for this anabolic element comes from a recent study that showed rats who completed 4 weeks of swimming exercise combined with zinc supplementation had significant increases in testosterone levels and a decrease in blood lactate, compared to those who did not ingest zinc. These data are supported by a human study that involved elite strength athletes (wrestlers). The researchers reported that wrestlers who completed 4 weeks of exhaustive training without supplemental zinc had significant declines in testosterone and thyroid hormone levels; whereas, those who received daily zinc while training had augmented testosterone and thyroid hormone levels.
Kaya O, Gokdemir K, Kilic M, Baltaci AK. Zinc supplementation in rats subjected to acute swimming exercise: Its effect on testosterone levels and relation with lactate. Neuro Endocrinol Lett. 2006 Feb-Apr;27(1-2):267-70.
Kilic M, Baltaci AK, Gunay M, Gökbel H, Okudan N, Cicioglu I. The effect of exhaustion exercise on thyroid hormones and testosterone levels of elite athletes receiving oral zinc. Neuro Endocrinol Lett. 2006 Feb-Apr;27(1-2):247-52.
McClung JP, Tarr TN, Barnes BR, Scrimgeour AG, Young AJ. Effect of supplemental dietary zinc on the mammalian target of rapamycin (mTOR) signaling pathway in skeletal muscle and liver from post-absorptive mice. Biol Trace Elem Res. 2007 Jul;118(1):65-76.