Magnesium, zinc, and copper status in women involved in different sports.
Nuviala RJ,
Lapieza MG,
Bernal E.
Clinical Biochemistry Department, University Hospital, Zaragoza, Spain.
The dietary intake, serum levels, and urinary excretion of magnesium, zinc, and copper were studied in 78 women involved in different sports (karate, handball, basketball, and running) and in 65 sedentary women.
Seven-day, weighed-food dietary reports revealed that no group of female athletes reached the minimal intake recommended for magnesium (280 mg/day) and zinc (12 mg/day), although their values were superior to those of the control group. The estimated safe and adequate minimal intake of copper (1.5 mg/day) was amply surpassed by the basketball players and runners but was not reached by the handball players.
Serum levels and urinary excretion of magnesium, zinc and copper did not seem related either to their intake or to the type of physical activity performed. The influence of other factors such as nutritional status, bioavailability, intestinal absorption mechanisms, and muscle-level modifications might explain the differences between the different groups of female athletes.
So, diet doesn't cut it, but exercise doesn't exacerbate it.
Effects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and Catabolism
Colin D. Wilborn1, Chad M. Kerksick1, Bill I. Campbell1, Lem W. Taylor1, Brandon M. Marcello1, Christopher J. Rasmussen1, Mike C. Greenwood1, Anthony Almada2, & Richard B. Kreider1
Exercise & Sport Nutrition Lab, Baylor University, Waco, TX1; IMAGINutrition, Laguna Nigel, CA2. Journal of the International Society of Sports Nutrition. 1(2):12-20, 2004. Address correspondence to
Richard_Kreider@baylor.edu.
Received December 18, 2004/Accepted December 28, 2004/Published (online)
ABSTRACT
This study examined whether supplementing the diet with a commercial supplement containing zinc magnesium aspartate (ZMA) during training affects zinc and magnesium status, anabolic and catabolic hormone profiles, and/or training adaptations. Forty-two resistance trained males (27±9 yrs; 178±8 cm, 85±15 kg, 18.6±6% body fat) were matched according to fat free mass and randomly assigned to ingest in a double blind manner either a dextrose placebo (P) or ZMA 30-60 minutes prior to going to sleep during 8-weeks of standardized resistance-training. Subjects completed testing sessions at 0, 4, and 8 weeks that included body composition assessment as determined by dual energy X-ray absorptiometry, 1-RM and muscular endurance tests on the bench and leg press, a Wingate anaerobic power test, and blood analysis to assess anabolic/catabolic status as well as markers of health. Data were analyzed using repeated measures ANOVA.
ResultsResults indicate that ZMA supplementation during training does not appear to enhance training adaptations in resistance trained populations. indicated that ZMA supplementation non-significantly increased serum zinc levels by 11 – 17% (p=0.12). However, no significant differences were observed between groups in anabolic or catabolic hormone status, body composition, 1-RM bench press and leg press, upper or lower body muscular endurance, or cycling anaerobic capacity. Journal of the International Society of Sports Nutrition. 1(2):12-20, 2004.
Full Study can be found here,
and is well worth the read.
If anything, that one is the most damning of all. Well controlled, using subjects much like the readers of D&S, and testing a myriad of different elements of fitness. Raised zinc by a whopping 17%. Woo. No buffering, no Mg, nada.
So, ZMA? Worth it?