science of ZMA

[saku]

how would having zinc, magneesium, and b6 increase your testosterone? i just started to take ZMA lastnight, not because i think im gonna have 30% more testosterone but because i wanted to sleep better. and i must say it does work for sleep and crazy dreams. but if somebody can tell me how its suppose to increase test that would be great.

cheers

[Errat1c]

taken from science in sport....

"ZMA is designed to be taken last thing at night on an empty stomach in order to optimise the absorbs ion, it is base on research which shows that hard training can deplete zinc and magnesium levels which can in turn lead to lower testosterone and insulin growth factor levels. By supplementing zinc and magnesium it has been shown that it is possible to maintain higher Insulin Growth Factor and Testosterone levels during periods of hard training. Zinc and magnesium levels are often shown to be low in athletic populations"

P.S what do you mean in crazy dreams??, i was thinking about purchasing ZMA for my sleep.

[Vadim Beliaev]

Keep in mind that it will only work if youre zinc and magnesium deficient. If you are supplementing with a good multi, chances are that ZMA will do absolutely squat to you. I suggest not to waste your money, and buy a good vitamin supplement like Animal Pak instead.

[OneBetter]

the above was pretty right on, if you're deficient in zinc, your test levels can be negatively effected. but if you get enough from your diet, i don't think extra zinc will do much. although, the magnesium does aid in sleep quality.

[The Brotherhood]

i dunno..my zinc/magnesium volumes shouldnt be low, i follow a solid diet and supplement with AST multipro 2x a day.

I dont know how to measure test increase, but if i take
ZMA at night the following day if and when i ejaculate the volume and thickness is more than normal. Test increasE? =/

[iron619]

Quote from the prominent Charles Poliquin from T-Nation regarding ZMA:

ZMA: Take It

About 54-75% of the American population is deficient in magnesium. Variation for zinc is somewhat greater. I've found that both zinc and magnesium are deficient in 100% of the athletes who come into my clinic. The higher their training volume, the greater their deficiency. When I gave ZMA to my athletes, virtually all of them reported better quality of sleep, an essential factor in maximizing recovery. About 70% of them noted an increase in morning libido. If you're active, the odds that ZMA will enhance your performance in the gym are high. Expect the results to be the greatest after 6 weeks of use.

Personally, I take ZMA to maximize sleep quality; the dreams are just an added bonus.

I would like to read some medical journals, studies, or experiments conducted on ZMA. If anyone has anything, please post.

[bigmuscleserik]

Keep in mind that it will only work if youre zinc and magnesium deficient. If you are supplementing with a good multi, chances are that ZMA will do absolutely squat to you. I suggest not to waste your money, and buy a good vitamin supplement like Animal Pak instead.

agreee. dont waste your money. there are other options.

[deadaim]

I take animal pak and zma, really helps you sleep, and the dreams are wicked, its not so much that your dreams change its just theres more REM sleep so longer dreams.

[saku]

alright thanks guys,

i definatly noticed a deeper sleep just form one night in taling it. its been a while since i have had a dream(s) durring the night. but last night i had many (3-4). i cant wait for tonight.

cheers

[BigPappaSmurf]

Keep in mind that it will only work if youre zinc and magnesium deficient. If you are supplementing with a good multi, chances are that ZMA will do absolutely squat to you. I suggest not to waste your money, and buy a good vitamin supplement like Animal Pak instead.

If the multi contained calcium as well, wouldn't it interfere with the absorbtion of the ZMA?

[GeneticTweak]

I started taking ZMA about 2 weeks ago to help me sleep better. The dreams are pretty vivid and numerous. But now after 2 weeks I don't remember my dreams as easily as I did with the first few days, I just know that I had some. The stuff definately helps me sleep better and the dreams are intense.

[saku]

wow i must say that the ZMA is really working for me, i used to be tired sometimes even after 8.5 hours of sleep now iv been wakeing up on my own fully rested at 8 hours and this is only me 3rd night of taking ZMA.

[UnivofAZ2006]

okay when you say dreams, are talking the kind of dreams teens have, or some other dreams. Im lost somewhere.

[fayd]

Keep in mind that it will only work if youre zinc and magnesium deficient. If you are supplementing with a good multi, chances are that ZMA will do absolutely squat to you. I suggest not to waste your money, and buy a good vitamin supplement like Animal Pak instead.

This is simply untrue. For a variety of reasons, (competition, blocked absorption) a person receives essentially none of the minerals in their multi-vitamin. There's lots of information on that. Personally, I've taken ZMA, and get definite effects from it, some indicative of increased test. I get vivid dreams, increased confidence/aggression, and most shocking, if I don't orgasm for about 3 days, I'll get wet dreams. W/o ZMA, I would have to go weeks before this would happen, perhaps longer (never heard anyone else mention this though). To test whether regular zinc has the same effect, I recently bought zinc gluconate and have been taking two (50mg) per night on an empty stomach just like ZMA. I have noticed none of the 'sides' I get from ZMA, even though this form of zinc is supposed to be highly bioavailable. What I'm saying is ZMA is certainly superior to regular zinc and definitely to a multi.

[fayd]

http://www.sportsnutritionsociety.or...2-12-20-04.pdf

there's a study done in 2004 indicating that ZMA does nothing for resistance training. the other study, done in 1999 by victor conte (who invented and sells ZMA) showed the numbers often cited (10.5% increase in strength etc etc).

[Cyrus317]

If the multi contained calcium as well, wouldn't it interfere with the absorbtion of the ZMA?

Yes. People are missing the point of ZMA. Zinc is used up in the muscles through extended periods of physical exertion. Zinc also loses its ability to be properly absorbed by the body when in the presence of Calcium. Don't think of "deficient" as "malnourished." You can have a great multi and a great diet, and with some training, you still may be Zinc deficient. Maybe it doesn't work for everyone, but it sure as hell works wonders for me. I'm giving it the thumbs up.

[Boiler23]

**SORRY THIS WAS ALREADY LINKED ABOVE**


EFFECTS OF ZINC MAGNESIUM-ASPARTATE (ZMA) SUPPLEMENTATION
DURING TRAINING ON BODY COMPOSITION AND TRAINING ADAPTATIONS

B Campbell, J Baer, A Thomas, R Slonaker, A Vacanti, B Marcello, C Wilborn, C Kerksick, C Rasmussen, S Ounpraseuth, P Casey, R Wilson, M
Greenwood, C Earnest & R Kreider. Exercise & Sport Nutrition Lab, Baylor University,

ZMA supplementation has been purported to increase anabolic
hormone status and promote gains in strength and muscle
mass during training. 42 resistance-trained males (27±9 yrs;
178±8 cm, 86±14 kg, 18.1±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
(ZMASSPM®, Cytodyne LLC, Lakewood, NJ) 30-60 minutes
prior to going to sleep during 8-weeks of standardized
resistance-training. At 0, 4, and 8-weeks, subjects had DEXA
body composition determined and performed 1RM muscular
strength, 80% of 1RM muscular endurance, and Wingate 30-s
sprint cycling anaerobic capacity tests. Data were analyzed by
repeated measures ANOVA and are presented as means and
± standard deviation changes from baseline for the P and ZMA
groups, respectively. Although some trends were observed, no
significant differences were observed between groups in
changes in fat free mass (0.15±1.3; 0.73±1.5 kg, p=0.20), fat
mass (-0.08±1.0; -0.74±1.5 kg, p=0.12), percent body fat (-
0.07±1.2; -0.79±1.5 %, p=0.10), bench press 1RM (3.6±5.5;
5.6±5.9 kg, p=0.24), leg press 1RM (24.6±25; 25.4±32 kg,
p=0.92), bench press lifting volume (-51±206; 4±186 kg,
p=0.38), leg press lifting volume (480±1,022; 724±1,258 kg,
p=0.48), sprint peak power (0.9±10; 3.6±10 %, p=0.40), sprint
total work (8.0±29; 1.1±12.2 %, p=0.34), or sprint fatigue index
(-1.0±7.2; -0.2±8.7 %, p=0.76). Additional research is
warranted to further investigate the effects of ZMA
supplementation during training on body composition and
training adaptations.
Supported in part by Cytodyne Technologies (Lakewood, NJ)

[Lewa nua]

This is simply untrue. For a variety of reasons, (competition, blocked absorption) a person receives essentially none of the minerals in their multi-vitamin. There's lots of information on that. Personally, I've taken ZMA, and get definite effects from it, some indicative of increased test. I get vivid dreams, increased confidence/aggression, and most shocking, if I don't orgasm for about 3 days, I'll get wet dreams. W/o ZMA, I would have to go weeks before this would happen, perhaps longer (never heard anyone else mention this though). To test whether regular zinc has the same effect, I recently bought zinc gluconate and have been taking two (50mg) per night on an empty stomach just like ZMA. I have noticed none of the 'sides' I get from ZMA, even though this form of zinc is supposed to be highly bioavailable. What I'm saying is ZMA is certainly superior to regular zinc and definitely to a multi.

I get it too but much more extreme ( I also take universal n1-d(whoppin 1g of test levels) no orgasim or bye bye clean sheets (my wife's enjoying this neccsity) any way When I took zma at 19 signs were almost steroidial why?
cause your body reacts highly to everything you do, during bodybuilding it makes the highest smount of use of whatever you put in so in this case using it to raise test levels

[thinker]

talks about the ZMA , craze and how silly this author thought it was and it was just another brillaint scam , no biggie , no real science -Mandella was fired for his candid communication on ZMA . Three very cheap ingrediants , combine them , quote some sponsored excerpts from non-scientific uncontrolled studys and yes you have a multi million dollar item .

[green10]

Not saying you shouldn't supp zinc, but keep in mind that high levels of zinc (100+ mg/day) have been shown to significantly increase the risk of prostate cancer.

http://patient.cancerconsultants.com....aspx?id=17534

[thinker]

You are 100% correct , 75 milligrams or more have shown very bad results

[DUILEE]

ZMA didn't do anything in terms of helping me sleep. I think its a little overhyped in its ability to do so. I will admit though that even ****** doesn't put me to bed so maybe I'm just a freak.

[bongd]

ZMA didn't do anything in terms of helping me sleep. I think its a little overhyped in its ability to do so. I will admit though that even ****** doesn't put me to bed so maybe I'm just a freak.

Were you using ****** CR?

Maybe you just have a separate sleep disorder. When I had first taken ZMA my diet probably wasn’t as consistent and I was likely lacking both zinc and magnesium (not a big red meat eater), but it sure did knock my skinny ass out cold. I would have the most intense dreams ever. Some times when I had woken up from night terrors, I would glance over at my clock and notice that I had only been sleeping for an hour and a half to two hours, but I felt fully rested!!

I have recently tried ZMA with less than stellar results, but still some results nonetheless. Not as many intense dreams, but I still woke up feeling damn well rested considering how simple ZMA is. My diet’s better and I am likely getting more zinc from whole foods. But ZMA’s pretty cheap, pretty darn effective ime and shouldn’t be shrugged off. While I don’t think it jacks up your test levels by 30%, nor increase lean mass, I still think it’s a great sleep aid that a lot of people can likely benefit from! In a few months, I will be trying ZMA again and I’m positive that I’ll still see some good results in my sleep.

As far as busting a nut’s concerned, I don’t think that is the best way of measuring T levels. Go to the doc and ask for a blood test. If you wanna bust a fat nut, take a few grams of lecithin each day…. Funny story, once my ex-gf learned how to get good at giving gummers, she’d do it all the time. And when I started supplementing with lecithin, BANG! Huge wads (she didn’t mind though, she was a trooper )!! I did a bit of research and apparently porn stars ingest a gross amount like 20g a day (I was only getting a couple of g in a day iirc) and that was enough to notice a change.

[digital_entropy]

So, maybe it's just me but during my longer dreams I'm beating the **** out of things more than normal. Anyone else have this happen? Apparently, I'm a crazed muscle bound anger freak in my sleep.

[bongd]

It’s probably not to do with ZMA. Could be potentially from a T increase, but ZMA won’t make you more violent in your dreams. Dreams have a billion variables and meanings. Just remember that ZMA will toss you into a deeper sleep (there’s a lot of science behind REM, dreams, etc) so that’s probably why. Deeper sleeps.

I’m telling you, I’ve had some of the most wacked out, lucid and crazy dreams on ZMA, White Blood and Melatonin. It was far more intense than any psychedelic experiences I’ve ever had. My pineal gland was probably working over time and accidentally pumped out an acid hippy dosage of DMT or something. I tripped friggen balls and woke up feeling like I could deadlift my house.

[digital_entropy]

I tripped friggen balls and woke up feeling like I could deadlift my house.

Me too...go figure

[crackyflipside]

I ordered my first bottle of ZMA, I'll see if it works for me.

[Chrome Face]

Keep in mind that it will only work if youre zinc and magnesium deficient. If you are supplementing with a good multi, chances are that ZMA will do absolutely squat to you. I suggest not to waste your money, and buy a good vitamin supplement like Animal Pak instead.

I disagree with the deficiency argument. ZMA works period. It doesn't matter if your multivitamin says it contains certain amounts of zinc or if you supplement with zinc & magnesium tabs on their own. I've tried supplementing with all different kinds of zinc and magnesium(e.g. chelate, citrate...) and nothing compares to the ZMA formula. It works period.... and it's cheap as hell. Everybody who is against it has probably never used a quality ZMA supplement.

[Speedbuff]

RESEARCH SUPPORTIVE OF ZMA SUPPLEMENTATION

1. The effect of zinc depletion on muscle function was tested in 8 male subjects. After receiving 12 mg Zn/day for 17 days, the subjects received 0.3 mg Zn/day for either 33 or 41 days. The subjects were then divided into two groups for zinc repletion. Group A subjects received overnight infusion of 66 mg of Zn on Day 1 and 10 and then were fed 12 mg Zn/day for another 16 days. Group B subjects were fed 12 mg Zn/day for 21 days. Peak force and total work capacity of the knee and shoulder extensor and flexor muscle groups were assessed using an isokinetic dynamometer at baseline, at two points during depletion, and at repletion. Plasma zinc levels decreased by an average of 67% during depletion and remained 9% below baseline after repletion. The peak force of the muscle groups was not found to be significantly affected by acute zinc depletion, however, shoulder peak force (strength) was found to be reduced by 9.2% in the extensor muscles. Total work capacity (muscle endurance) for the knee extensor muscles and shoulder extensor and flexor muscles declined significantly by 28.1%, 24.1% and 26.4%, respectively. This study demonstrates that muscle endurance, or total work capacity, declines rapidly with acute zinc depletion and the degree of the decline was correlated with the reduction in plasma zinc concentration.

Van Loan, MD, et al. The Effects of Zinc Depletion on Peak Force and Total Work of Knee and Shoulder Extensor and Flexor Muscles. Int J of Sport Nutr, June 1999, Vol. 9, No. 2, 125-135.

2. A study was conducted to determine the effects of magnesium supplementation on strength development during a double-blind, 7-week strength training program in 26 untrained subjects (14=placebo, 12= Mg), 18-30 years old. Pre and post peak quadriceps torque (leg press) measurements were made using an isokinetic dynamometer. The leg muscle strength of the magnesium supplemented group significantly increased by 26%, compared to only 10% for the placebo group.

Brilla, LR, et al. Effect of Magnesium Supplementation on Strength Training in Humans. J Am Coll Nutr, July 1992, Vol 11, No. 3, 326-329

3. Serum zinc levels were determined in 160 training athletes (103 males and 57 females). In 23.3% of male and 43% of female athletes, serum zinc was significantly below the "normal range".

Haralambie, G. Serum zinc in athletes in training. Int J Sports Med 2 (1981) 135-138.

4. Magnesium, zinc and copper status of 270 US Navy Sea, Air and Land (SEAL) trainees was determined from dietary intakes and biochemical profiles. The dietary intakes of 34% and 44% of the trainees were below the RDA for Mg and Zn, respectively. The blood plasma concentrations of Mg and Zn were significantly below the "normal range" for 23% and 24% of the trainees, respectively.

Sing A, et al. Magnesium, Zinc and Copper status of US Navy SEAL trainees. Am J Clin Nutr 1989;49:695-700.

5. Serum zinc levels were measured in 20 adolescent gymnasts (9 boys, 11 girls, age 12-15). They had 26% lower serum zinc levels (0.599 +/- 0.026 mg/l) when compared to 118 matched controls (0.810 +/- 0.014, p < 0.001). The gymnasts serum zinc levels were positively correlated with adductor strength (r=0.468, p < 0.05). The 11 of 20 gymnasts with serum zinc < 0.6 mg/L had lower insulin-like growth factor binding protein 3 levels than the others (2.326 +/- 0.064 vs 2.699 +/- 0.12, p < 0.01). This protein is supposed to reflect growth hormone activity. Thus, zinc is lowered in trained adolescent gymnasts and this reduction could play a role in abnormalities of growth or muscular performance.

Brun J, et al. Serum zinc in highly trained adolescent gymnasts. Bio Trac Elem Res, 1995, Vol. 47, 273-278.

6. Twenty-one professional football (soccer) players underwent a maximal exercise test on a cycloergometer, with progressively increasing workloads until VO2max. On the whole these subjects had low serum zinc because nine (43%) of them had a hypozincemia (0.54 +/- 0.01 mg/L) which suggested a zinc deficiency. The subjects with low serum zinc had a 26% lower power output (123 +/- 8.71 vs. 166.27 +/- 14.84 watts, p = 0.029) and exhibited a 35% higher increase in blood lactate (lactic acid) during exercise (7.51 +/- 0.81 vs. 5.57 +/- 0.33 mmol/L, p <0.04) resulting in a 24% lower 2 mmol lactate threshold (44.7 +/- 3.9% vs. 58.9 +/- 4.8% of maximal power output p < 0.04). In conclusion, this study suggests that zinc status may influence blood rheology (flow) during exercise by an effect related to lactate accumulation.

Khaled S, et al. Serum zinc and blood rheology in sportsmen (football players. Clin Hemo and Micro 17 (1997) 47-48.

7. Ten collegiate basketball players serum mineral levels were measured before official practice began and immediately following the competitive season. Diets were monitored and remained the same throughout the four month period. Mean serum values for Mg and Zn decreased pre-season to post- season by 16% and 41%, respectively.

Lefavi RG, et al. Reduced serum mineral levels in basketball players after season. Med and Sci in Sports and Exer. Vol. 27, No. 5, May 1995

8. Twelve professional volleyball players and 12 control subjects were studied to determine the effects of daily physical training on serum, sweat and urine zinc concentrations. The professional athletes trained every day in two sessions, one in the morning (work in the gym for 2 hours) and another in the afternoon (specific work on the sports field for 3 hours). Simultaneously, 12 male volunteer university students, who were moderately trained, participated as the control group. The study was conducted over a period of 10 weeks. Pre-post tests were made using a progressive bicycle ergometer (increasing 30 W every 3 minutes to reach a maximum tolerated power). Pre-post blood samples were obtained at rest and immediately following exercise. After ten weeks of training, the professional athletes showed a significant increase in 24 hour urinary zinc excretion (22% greater losses), in contrast to a slight decrease (2% less) in the controls. The athletes also showed a very significant increase in the zinc loses in sweat compared to the controls. The athletes sweat zinc concentrations increased by an astounding 300%, compared to only 30% increases in the control group. The athletes serum zinc levels decreased by 4%, compared to a 2% decrease in the control group. Finally, the post exercise cortisol levels of the athletes significantly increased by 93%, compared to only an 18% increase in the controls. The authors stated that the athletes "cortisol levels increased in response to the exercise work load stress, and this behavior seems to be related to muscular damage". The authors went on to say that "It seems that the changes in zinc metabolism found in the study may be damage, increased protein turnover and increased zinc excretion (via sweat and urine). Because strenuous exercise during a period of competition can induce a "catabolic state" and has been shown to increase skeletal muscle protein turnover, it is likely that urine zinc is derived from muscle tissue". The authors concluded by saying that "Zinc supplementation and/or stress control appear to be indicated in athletes. In our practical opinion, we think that alterations in zinc metabolism with increases in zinc excretion and stress levels lead to a situation of latent fatigue with a decrease of endurance".

Cordova A, et al. Effect of training on zinc metabolism: changes in serum and sweat concentrations in sportsmen. Ann Nutr Metab, 1998 42:5, 274-82.

9. Plasma zinc, iron, copper and selenium levels were measured in 66 Navy SEAL trainees before and after a 5 day period of sustained physical and psychological stress called "Hell Week". The trainees pre-post plasma zinc levels decreased by 33%.

Singh A, et al. Biochemical indices of selected trace minerals in men: effect of stress. Am J Clin Nutrition 1991; 53:126-31.

10. Nine healthy, male subjects (18-40 years) were supplemented daily with 365 mg of magnesium as aspartate for 14 days. Before and after the supplementation period each subject performed a rigorously identical one hour ergometer exercise. The magnesium supplementation significantly reduced the subjects plasma levels of the catabolic "stress" hormone cortisol by an average of 25% (P < 0.025), which remained decreased during the exercise. The magnesium also significantly lowered the subjects' heart rates throughout the exercise period by an average of 8% (P < 0.03). Golf SW, et al. Plasma aldosterone, cortisol and electrolyte concentrations in physical exercise after magnesium supplementation. Clin Chem Clen Biochem, 1984, Vol. 22, pp. 717-721.

11. Medical students were tested to determine the acute effect of zinc supplementation on cortisol levels. The test was started at 7:00 AM after a 12 hour fast. Serial blood samples were collected from an experimental zinc group and controls at 30 minute intervals for 240 minutes. A subgroup of 7 subjects (3 men, 4 women) ingested 25 mg of zinc immediately after the baseline collection and their cortisol levels were compared to 8 matched controls who received a placebo. The control group started out with an average cortisol level of 11 mcg/dL and fell to 9 mcg/dL at 240 minutes, which is an 18% reduction. The zinc supplemented group started out with an average cortisol level of 16 mcg/dL and significantly dropped to 6.5 mcg/dL, which is a 59% reduction. In summary, the zinc supplemented group had a 41% greater reduction in cortisol levels compared to controls. The fact that zinc inhibits basal cortisol secretion in humans may be related to a direct blockade of cortisol synthesis and secretion in the adrenal cortex.

Brandao-Neto J, et al. Zinc acutely and temporarily inhibits adrenal cortisol secretion in humans. Bio Trace Elem Res, 1990, Vol. 24, 83-89.

12. Nine men participated in an 85 day zinc depletion/repletion study divided into 3 metabolic periods: 18 day baseline, a 44 day depletion, and a 23 day repletion. 12 mg of zinc per day was fed to the men during baseline and were held constant after adjustments during the baseline period. Plasma zinc declined from 77.1 +/- 0.03 mcg/dl at baseline to 28.1 +/- 0.07 mcg/dl at depletion; concentrations returned to 77.9 +/- 0.03 mcg/dl at repletion. Total body weight, fat, fat-free mass (FFM), and bone mineral did not change during depletion, but total body water increased 5.3% +/- 1.9%, or about 2 kg or 4.4 lbs (P <0.05) by the end of the depletion and returned to baseline values at the end of repletion. The percent water in FFM increased from 71% +/- 1 to 75% +/- (P <0.05) at the end of depletion and was associated with a small decrease in body protein. The data suggest that zinc depletion impairs water balance.

Sutherland B, et al, Effect of experimental zinc depletion on body composition and basal metabolism in men. The FASEB Journal, Mar. 10, 1995, Volume 9, Number 4.
__________________
SNAC System

[Sldge]

Maybe you should post studies that represent 99% of the users on this forum instead of posting studies done on starving sleep deprived Navy Seals or professional athletes working out 5+ hours everyday.

Here are 2 that you seem to have missed, RESEARCH NOT SUPPORTIVE OF ZMA:

J Int Soc Sports Nutr. 2004 Dec 31;1(2):12-20.
Effects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and Catabolism.
Wilborn CD, Kerksick CM, Campbell BI, Taylor LW, Marcello BM, Rasmussen CJ, Greenwood MC, Almada A, Kreider RB.

Exercise & Sport Nutrition Lab, Baylor University, Waco, TX.

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. Results 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. Results indicate that ZMA supplementation during training does not appear to enhance training adaptations in resistance trained populations.


Eur J Clin Nutr. 2009 Jan;63(1):65-70. Epub 2007 Sep 19.Click here to read Links
Serum testosterone and urinary excretion of steroid hormone metabolites after administration of a high-dose zinc supplement.
Koehler K, Parr MK, Geyer H, Mester J, Sch?nzer W.

1Institute of Biochemistry, German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany.

Objectives:To investigate whether the administration of the zinc-containing nutritional supplement ZMA causes an increase of serum testosterone levels, which is an often claimed effect in advertising for such products; to monitor the urinary excretion of testosterone and selected steroid hormone metabolites to detect potential changes in the excretion patterns of ZMA users.Subjects:Fourteen healthy, regularly exercising men aged 22-33 years with a baseline zinc intake between 11.9 and 23.2 mg day(-1) prior to the study.Results:Supplementation of ZMA significantly increased serum zinc (P=0.031) and urinary zinc excretion (P=0.035). Urinary pH (P=0.011) and urine flow (P=0.045) were also elevated in the subjects using ZMA. No significant changes in serum total and serum free testosterone were observed in response to ZMA use. Also, the urinary excretion pattern of testosterone metabolites was not significantly altered in ZMA users.Conclusions:The present data suggest that the use of ZMA has no significant effects regarding serum testosterone levels and the metabolism of testosterone in subjects who consume a zinc-sufficient diet.European Journal of Clinical Nutrition (2009) 63, 65-70; doi:10.1038/sj.ejcn.1602899; published online 19 September 2007.