Does ZMA Actually Work?
For my fifth article on dietary supplements used by athletes, I am going to review the supplement ZMA or Zinc Magnesium Aspartate. One of the most commonly asked questions about this supplement that I’m asked is, “Does ZMA work?
Ingredients in ZMA
Common preparations of ZMA include the ingredients: Zinc, Magnesium, and Vitamin B6. Some ZMA formulations add various other ingredients to make their product unique.
Who invented the ZMA formulation?
To provide some historical context, ZMA was developed by Victor Conte (founder of Balco). Balco or the Bay Area Laboratory Co-operative, who became infamous for its implication in a steroid scandal involving numerous Olympic athletes who have subsequently lost their medals including Marion Jones. In particular, the steroid tetrahydrogestrinone (THG), which was often referred to as “the clear,” was an undetectable performance enhancing steroid used by these athletes.
Okay, now does ZMA actually work?
Though several companies market various ZMA type products, the current evidence that these products have any effect on strength, hormone status, or body composition is currently lacking . Researchers at Baylor University in Texas published the results of an 8-week study made the follow conclusions:
“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. Results indicate that ZMA supplementation during training does not appear to enhance training adaptations in resistance trained populations” .
In summary, the study in 2004 by Wilborn et al found that ZMA did not work at all for enhancing anabolic hormone status, increasing muscle mass, improving strenght, or enhancing endurance or anaerobic capacity. The participants in this study included 42 resistance trained males who took the supplement prior to resistance training for a total of 8 weeks.
What was in the ZMA supplement for this study?
The ZMA supplement used in this study was provided by Cytodyne Technologies called Zmass PM™. It contained the follow ingredients:
- 11 mg of Vitamin B-6 (pyridoxine hcl)
- 30 mg of zinc (as monomethionine and aspartate)
- 706 mg of a proprietary blend of mucuna pruriens (seeds) standardized for 50 mg of L-Dopa (purported as a muscle relaxant) and Polypodium Vulare/Suma root (herb) standardized for 30 mg of 20-hydroxyecdysone (a plant sterol purported to reduce catabolism).
Does ZMA increase testosterone levels?
A more recent study published by German researchers in the European Journal of Clinical Nutrition found that supplementation with ZMA did not enhance either free or total serum testosterone levels . This particular study included 14 healthy men who engaged in regular exercise.
Bottom line: Don’t waste your money!
From the current studies available regarding the lack of effectiveness at ZMA supplementation for improving body composition, strength, endurance, or improving testosterone levels, you probably shouldn’t waste your money on this supplement.
- Wilborn CD, Kerksick CM, Campbell BI, Taylor LW, Marcello BM, Rasmussen CJ, Greenwood MC, Almada A, Kreider RB. Effects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and Catabolism. J Int Soc Sports Nutr. 2004 Dec 31;1(2):12-20
- Koehler K, Parr MK, Geyer H, Mester J, Schänzer W. Serum testosterone and urinary excretion of steroid hormone metabolites after administration of a high-dose zinc supplement. Eur J Clin Nutr. 2009 Jan;63(1):65-70. Epub 2007 Sep 19.