Sleep Like an Athlete: Supplement Smart to Complement, not Replace Periodization & Basic Rules of Sleep Hygiene

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Blindfolds and earplugs can improve your sleep quality significantly. The special beauty of blindfolds is: unlike earplugs, blindfolds may also be used to refresh 'other things' you may be doing beneath or on top of your sheets, which in turn will help those who are struggling with getting restorative sleep (learn more)

While every idiot will tell you that ZMA is "the shit" (it indeed is, literally) its purported benefits are either insufficiently proven or even disproven, as it is the case for the alleged  anabolic effect of ZMA, which clearly don't exist (Wilborn 2004) outside of the "alternative facts" supplement companies use in pamphlets people call "write ups". Obviously, this won't stop the bros at the gym from telling you: "Dat ZMA gives me an amazingly anabolic sleep, bro!"

The reasons ZMA (unfortunately) hasn't disappeared, yet, is still in the TOP10 of an unfortunately high number of supplement retailers' sales-lists, though, is not only bropaganda. It's bropaganda that appears plausible, because both, B-vitamins and magnesium, play an important role in the physiology of human sleep.
It is thus only logical that they made it on a list scientists from Portugal and Spain compiled and published in "Arch Med Deporte" in form of a review. A review which does, unlike a dozen of articles on fitness websites, mislead its readers to believe that supplements were the basis or at least necessary for optimal sleep in athletes.

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Figure 1: Rules of optimal sleep hygiene for athletes - Sleep hygiene measures that may contribute to improving the quantity and quality of sleep in athletes (from Ordóñez 2017).

You wouldn't have believed such bogus, anyway, would you? I mean, we all know that the basis of optimal sleep ain't different for athletes vs. couch potatoes, it's always sleep hygiene. The rules of sleep hygiene, on the other hand, may well differ. Periodization and a sensible control of one's training volume and intensity, for example, are nothing you'd find on the average couch potato's list because he's already training way too little to get optimal sleep.
For you, who is obviously not a sedentary couch potato, my first advice to "fix your sleep" is thus: make sure you're not following the invalid "more helps more" approach and have been overtraining for weeks (that's in contrast to overreaching | learn more). When you've your sleep hygiene ducks in a row, go ahead and read the following paragraphs about supplements:

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  Figure 1: Changes in sleep in response to TRYP (Silber 2010).

  the serotonin precursor tryptophan- while it is unquestionably essential for optimal sleep, the amount of the serotonin precursor tryptophan in our diet is usually more than high enough to fulfill our dietary requirements;
  
  still, if your intake is low and/or your requirements are increased (e.g. low niacin intake and/or requirements of the tryptophan based-vitamin) or you've been stupid enough to block the entry of tryptophan into the brain by guzzling BCAAs all day (learn more), taking at least 1g (best consumed on empty) before going to bed may help you fall asleep and improve subjective sleep quality
• vitamins from the B-complex - yes, here it is B-vitamin, but the infamous B6 (pyridoxin) from ZMA, is required only in very low doses and together with folate as a co-factor in serotonin synthesis; in fact, taking too much (which is what you will find in most ZMA products) can ruin your sleep by giving you the weirdest kind of dreams;

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  Figure 1: Possible mechanisms of the influence of dietary components on the synthesis of serotonin and melatonin (from Peuhkuri 2012). One thing you should remember, though: Most of us get all the necessary nutrients from our diet, accordingly you must not expect exorbitant benefits from taking supplements.

  often forgotten, but at least as important, especially for athletes, whose requirements may be significantly increased, is vitamin B3 aka niacin, the endogenous production of which will otherwise be favored by your body over the synthesis of serotonin from tryptophan (Peuhkuri 2012); some evidence also exists for B12, which is necessary for the proper synthesis of melatonin, and should thus have possible positive effect on the quantity of sleep, especially in vegetarian athletes, who often don't get enough B12 from their meatless and thus in many cases cobalamine-deficient diet
• overrated, but important magnesium - while there's little doubt that magnesium is important for the 5-Hydroxytryptamine enzyacetyltransferase to convert 5-HT into N-Acetyl-5-Hydroxytryptamine and which is then transformed into N-Acetyl-5-methoxy tryptamine aka Melatonin, there's little evidence that taking extra Mg has beneficial effects on sleep; in fact, scientists have yet to establish, if low magnesium is the cause of just a corollary factor of sleep problems (Nielsen 2010 | this could still mean that Mg supplementation will solve the underlying problems that keep you awake, though) and beneficial effects of supplementation have only been established in elderly subjects (Abbasi 2012), where it has been found to reverse the age-related neuroendocrine and sleep EEG changes (Held 2002)

No such conclusive evidence exists for zinc, the third ingredient in the supplement everybody will name when you ask for "sleep supplements for athletes". While an older rodent study suggests that a full-blown zinc deficiency goes hand in hand with reduced melatonin levels (Abbasi 2012), there's no evidence that zinc deficiency is (a) causally involved, (b) a major problem in the average athlete and (c) no human data to support improved sleep with zinc. Similarly promising, but not fully convincing evidence exists for

• GABA and phenibut, which I've discussed in detail (see "GABA - An Effective Sleep Aid W/ GH Boosting Effects that Works Within 30 Minutes - Only 100 mg Pre-Bed Will Suffice" | read it, and "Phenibut, Addictive Sleep Aid With Unhealthy Hangover? Dosages, Effects, Side Effects and Safety Concerns" | read it), ...
• plain dietary calciumand potassium, which are, much like magnesium, essential for protein encoding that facilitates sleep and regeneration, ...
• dietary (or supplemental) L-ornithine, the anti-stress effects of which I've likewise addressed in previous articles ( "L-Ornithine an Anti-Stress Agent: Lower Cortisol, Higher DHEA, Better Sleep W/ Only 400mg of Ornithine Pre-Bed" | read more) and 
• reduced intakes of palmitic acid (aka hexadecanoic acid), which have been found to be significantly associated with difficulties falling asleep (Grandner 2014).

All these dietary links that have been outlined quite nicely by Zeng et al. a 2014 paper about their potential use in functional foods (see Figure 3):

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Figure 3: Possible mechanisms of functional components in foods promote sleep (from Zeng 2014).

Certainly effective in some, but highly debated among both scientists and practitioners, is the last supplement on the list: melatonin. Useful dosages for athletes appear to range from 3-12 mg with higher doses not necessarily working better, but increasing the risk of side effects ranging from headaches over nausea and drowsiness during the day or nightmares, all of which could potentially negatively affect your performance. I would thus not necessarily call melatonin a "must have" supplement for athletes - well,... unless you're traveling over several time zones regularly. In that case, you can use it to combat jet lag and reprogram your internal clock; or, as a Cochrane Review says you could use its "remarkabl[e effectivity] in preventing or reducing jet lag [... whenever you cross] five or more time zones, particularly in an easterly direction, and especially if [you have experienced jet lag on previous journeys" (Herxheimer 2002).
References:

• Abbasi, Behnood, et al. "The effect of magnesium supplementation on primary insomnia in elderly: a double-blind placebo-controlled clinical trial." Journal of Research in Medical Sciences 17.12 (2012).
• Grandner, Michael A., et al. "Sleep symptoms associated with intake of specific dietary nutrients." Journal of sleep research 23.1 (2014): 22-34.
• Held, Katja, et al. "Oral Mg2+ supplementation reverses age-related neuroendocrine and sleep EEG changes in humans." Pharmacopsychiatry 35.04 (2002): 135-143.
• Herxheimer, Andrew, and Keith J. Petrie. "Melatonin for the prevention and treatment of jet lag." The Cochrane Library (2002).
• Ordóñez, Fernando Mata, et al. "Sleep improvement in athletes: use of nutritional supplements." Nº 135 (Murc Tlf (2017): 93.
• Nielsen, Forrest H., LuAnn K. Johnson, and Huawei Zeng. "Magnesium supplementation improves indicators of low magnesium status and inflammatory stress in adults older than 51 years with poor quality sleep." Magnesium Research 23.4 (2010): 158-168.
• Peuhkuri, Katri, Nora Sihvola, and Riitta Korpela. "Diet promotes sleep duration and quality." Nutrition Research 32.5 (2012): 309-319.
• Silber, B. Y., and J. A. J. Schmitt. "Effects of tryptophan loading on human cognition, mood, and sleep." Neuroscience & Biobehavioral Reviews 34.3 (2010): 387-407.
• Wilborn, Colin D., et al. "Effects of zinc magnesium aspartate (ZMA) supplementation on training adaptations and markers of anabolism and catabolism." Journal of the International Society of Sports Nutrition 1.2 (2004): 12.
• Zeng, Yawen, et al. "Strategies of functional foods promote sleep in human being." Current signal transduction therapy 9.3 (2014): 148-155.