June 2, 1999–Lorrie Brilla, Ph.D., a sports performance researcher at Western Washington University, announced today that a novel zinc-magnesium supplement called "ZMA" significantly increased muscle strength in NCAA football players.
The ZMA study results are being presented today by Dr. Brilla at the 46th Annual Meeting of the American College of Sports Medicine in Seattle, Washington. These findings were recently published in the official ACSM journal, Medicine & Science in Sports & Exercise, Vol. 31, No. 5.
According to Dr. Brilla, "A group of competitive NCAA football players who took ZMA nightly during an 8 week spring training program had 2.5 times greater muscle strength gains than a placebo group. Pre and post leg strength measurements were made using a Biodex isokinetic dynamometer." The strength of the ZMA group increased by 11.6% compared to only a 4.6% increase in the placebo group.
"The muscle strength increases may have been mediated by the anabolic hormone increases in the ZMA group. The ZMA group had 30% increases in free and total testosterone levels compared to 10% decreases in the placebo group. The ZMA group also had a slight increase in insulin-like growth factor-1 (IGF-1) levels compared to a 20% decrease in the placebo group. This study shows that anabolic hormone and muscle strength increases can be induced in already strength-trained athletes by using a novel zinc-magnesium preparation", said Brilla.
According to co-investigator Victor Conte, Director of BALCO Laboratories in Burlingame, California, "ZMA is the only all natural product that has been clinically proven to increase anabolic hormone levels and muscle strength in trained athletes." The dosage of ZMA used in the study contains 30 mg of zinc and 450 mg of magnesium. "There has never been a study reporting adverse health effects at these moderate dosages." said Conte.
John Gamble, strength and conditioning coach for the Miami Dolphins, reports that "players using ZMA are cramping much less and seem to be getting a more deep and restful sleep which enhances their recovery".