Trace elements play a pivotal role in the body's manufacture and use of energy, which is important for adequate physical performance and general health (Nuviala, Lapieza & Bernal, 1999). Because iron deficiency is widely reported in female athletes, it is of interest to focus on other trace elements such as zinc and copper. Athletes experience increased losses in micronutrients via sweat and urine, especially during prolonged activity. However, micronutrient deficiency may be aggravated in athletes who restrict their energy intakes to reduce body mass, often observed in long distance runners. This being so, there is a need to control micronutirent intake to maintain performance.
A study of 78 sportswomen involved in different sports (karate, handball, basketball and running) revealed that no group of female athletes, consumed the minimal recommended daily intake for magnesium (280mg/daily) or zinc (12mg/daily) (Nuviala, Lapieza & Bernal, 1999). The estimated recommended daily intake of copper (15mg/daily) was amply surpassed by female basketball players and runners, yet unreached by handball players (Nuviala, Lapieza & Bernal, 1999). Moreover, it was reported that the caloric intake of female athletes involved in running and karate was insufficient to cover the energy requirements for their sport. This being so, it is of little surprise that Nuviala, Lapieza & Bernal (1999) encourage athletes to use a magesium and zinc supplement to ensure recommended daily intake is met. Although, the type of physical activity was not shown to influence serum status and urinary excretion, bioavailability and intestinal absorption mechanisms were strongly indicated. For this reason, quality forms of magnesium and zinc are required to improve bioavailability and intestinal absorption.
Nuviala, R.J., Lapieza, M.G & Bernal, E. 1999. Magnesium, zinc and copper status in women involved in different sports. International Journal of Sports Nutrition, 9, 295-309.