Optimal nutrition enhances physical performance. It makes sense, but the point may not be quite so obvious when it comes to sports in which muscle building or fat loss is desired. In the past 10 years, there’s been a remarkable increase in the availability of bodybuilding supplements. Many have been widely studied, while others have only theoretical promise.

Stacking, Defined
Stacking is the method of using multiple supplements in an effort to augment athletic performance gains. A term originally applied to anabolic steroids, stacking has found its way into the natural-supplement world. In the face of mounting condemnation and public awareness about the dangers of steroids, natural bodybuilding supplement stacks have emerged.

Natural Stacks
These stacks contain a variety of supplement products. The practice has become so widespread that some products now offer pre-mixed combinations of supplements. Also, some manufacturers offer advice on how best to stack their supplements. BSN, for example, advocates stacking its products in a pyramid that may include Axis-HT, N.O.-Xplode, Nitrix, CellMass, Thermonex, Cheaters Relief, and Lean Dessert Protein.

Stack Breakdown
Of the various types of bodybuilding-supplement stacks, the most common are for muscle building, fat loss (also known as shredding), and muscle recovery. Muscle-building and muscle-recovery stacks are similar; a basic stack of this type will typically contain creatine, glutamine, protein, multivitamins, and amino acids. Creatine is arguably the most popular oral supplement among top-level strength and speed athletes. It has been demonstrated to enhance muscular development in response to weight training. Glutamine is reported to increase muscle recovery following strength training. Research has proven that strength athletes require an increased amount of protein compared to nonathletes to build and maintain muscle mass. Finally, multivitamins and branched-chain amino acids (BCAAs) assist with muscle recovery through the stimulation of protein synthesis.

Medicine Looks at Stacks
Medical literature is beginning to address these training stacks. The majority of research is done using protein, creatine, and glutamine in various combinations. Thus far, studies show that subjects using combinations of these supplements have increased muscle strength. More studies are needed to confirm that this combination leads to an increase in overall muscle mass, although current studies tend in this direction. These products have a good safety profile in most individuals; however, they may be unsafe in the presence of kidney or heart failure.

Play It Safe
Fat-loss or shredding stacks typically contain bitter orange extract (Citrus aurantium)—a source of synephrine—as well as natural sources of caffeine and aspirin. Bodybuilders needing to shed weight before a contest often use these products. Though they may be effective as performance-enhancing supplements, they should be used with great caution. They can lead to dehydration, elevated blood pressure, insomnia, nervousness, irritability, and artery constriction in the brain and heart.

Before using a stacking product:

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  Be a student of nutrition. Learn how to achieve a balanced, healthy diet for your sport.

  
  


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  Use stacking products only in association with a prudent diet and sound training.

  
  


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  Be patient with weight loss and muscle gains. A great physique is not built in a day.

  
  


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  Review the list of banned substances before entering a sports competition. Many stacking products are banned by some sports organizations.

  
  


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  Review any supplements you take with your health-care provider.

  
  

—Marie President, M.D.