In a sports-nutrition segment that maintains its margins and avoidance of commodity pricing through innovation, the drive for 'the next best thing' is always at the forefront. As sports-nutrition and weight-loss products move in and out of speciality and mass channels, Mark J Tallon, PhD, investigates the latest trends and challenges facing the category in 2007

It was the best of times and it was the worst of times in the sports and weight-loss segment in 2005. Although the category as a whole increased by seven per cent in 2005 from $15.6 billion, according to Nutrition Business Journal, many categories are in decline, especially within the weight-loss market.1 Many of the larger companies are branching into mass-market channels and away from the core-nutrition segment. However, they still require innovative ingredients to maintain strong brand loyalty and keep their consumers away from myriad copy cats.

Following the increase in media attention regarding dietary-supplements contamination, and athletes testing positive for banned substances, the industry turned to purity testing and certification programmes to overcome supplement-contamination issues. Commercial and World Anti-doping Authority (WADA)-accredited analytical labs offer their own brand of testing to help protect the elite athlete and consumer from these illicit substances. However, are these organisations really providing a service that protects the public interests? What are the strengths and weaknesses of these different certification programmes? And finally, where does the future lie for product testing? The following gives an overview of those ingredients set to push the category forward in 2007 and beyond.

Beta-Alanine: New Kid In Town
Carnosine is an imidazole dipeptide composed of beta-alanine and histidine. It appears to hold such great promise because of its multiple roles within muscle tissue, including acting as an antioxidant and enhancing the body's ability to buffer fatigue-causing hydrogen ions often associated with such feelings as 'the burn' during intense exercise.2

The body's ability to buffer the accumulation of hydrogen ions is often the limiting factor for the number of sets and reps one can ultimately perform during high-intensity exercise. Because beta-alanine is the rate-limiting nutrient in the synthesis of carnosine,3 and is also less expensive than carnosine, the take-home message is it gives more bang for the buck.

Recent work has defined further its specific role in the enhancement of sports performance by controlling (buffering) the detrimental performance effects of low pH levels in muscle tissue.3 The result is an enhancement in the length of time a set intensity can be maintained during exercise.4 The suggestion is this enhancement of intracellular carnosine will not only lead to a rapid increase in performance but also greater gains in muscle strength and endurance.5

A host of products include beta-alanine as a central ingredient. There are still questions regarding beta-alanine as a sports supplement, including long-term safety, correct dosing (leading to muscle saturation); and optimal timing. Even with these questions outstanding, it is believed across the industry that beta-alanine is here to stay. However, whether its effectiveness will eclipse the success found with creatine in the mid-1990s is yet to be seen.

RTDs and MRPs Get Fortified
Leucine is one of the branched-chain amino acids that has become the 'now nutrient' present within most liquid hydrolyzed-protein-based products. Pioneering research shows that leucine has some unique properties in relation to muscle growth exceeding that of the vast majority of other amino acids.6^,7^,8 Studies have shown that leucine can significantly enhance recovery from exercise, leading to greater gains in strength and muscle mass for the effort.8 This has caused those within the speciality channels of sports nutrition to use it as a hook for both the hard-core bodybuilder and fitness enthusiast.

Other innovations likely to stir interest in 2007 include a new class of enzymically altered and filtered proteins such as casein-derived di/tripeptide products. These peptide products are high in fast glutamine peptides, and have been shown to enhance insulin release and, when used in conjunction with carbohydrates, can accelerate recovery.9 This has led to greater interest in incorporating protein into traditional carbohydrate-heavy sports drinks. One such product contains a patented 4:1 ratio of carbohydrates to protein to speed muscle glycogen replenishment and rebuild muscle protein after exercise. Another key difference is whether the protein peptides are hydrolysed or not.

The Nox Revolution
The 2002 release of a branded sustained-release arginine-alphaketoglutarate ingredient (AAKG) has led to a flood of products claiming to enhance the release of the chemical nitric oxide. The science behind these products relates to increased nutrient delivery and muscle stimulation from higher levels of nitric oxide.¹⁰ AAKG as a precursor to nitric oxide is presumed to be better than arginine. However, the science regarding its efficacy as a significant enhancer of body composition is equivocal based on recent clinical-trial work.

In a study from the world-renowned Baylor University in Texas, researchers assessed the adaptive responses of AAKG product vs a nonsustained release AAKG to resistance training.11 This study was not without its flaws, including some conclusions. Firstly, the study did not compare the two forms of AAGK regarding training adaptations. Secondly, the pharmacokinetic aspect of the study did compare the two AAKG forms, and the authors state a difference. However, according to their own data presented within the manuscript, no statistically significant difference was evident between mean plasma arginine between groups or area under the curve.

Although compared to placebo there were some significant adaptations to training following the sustained- release group (single-rep bench press — a measure of strength — as well as peak power, blood glucose and plasma arginine), no change was seen in body composition or aerobic capacity. Given that no pharmacokinetic difference was present between the sustained-release or nonsustained-release AAKG, there is no rationale as to why the sustained version would be any better — though the AAKG was superior to placebo in some ways. Clearly, more research is required.

Creatine the Commodity
Creatine is one of the more popular sports-nutrition products, and is now finding potential applications within the medicinal field of muscle-disease states — though this research is still preliminary and not yet a source of revenue for any company. As a commodity ingredient within the sports category, it was of no surprise to see creatine sales fall to $220 million in 2005, as reported by NBJ.1

However, recent advancements in nutricosmetic research may provide an additional avenue for creatine sales. Researchers in Germany found that human skin cells that are energetically recharged with the naturally occurring energy precursor, creatine, are markedly protected against a variety of cellular stress conditions, like oxidative and UV damage in vitro and in vivo.12

In another twist to the creatine story, the buffered, so-called pH-stable (does not degrade in stomach, leading to higher bioavailability) creatine products have attempted to revitalize the market. Furthermore, creatine-based products without NDI approval, such as creatine ethyl ester (CEE), are purported to enhance solubility.

Problems related to the evidence behind these products' safety and/or efficacy have arisen, given no published data exist to support claims, such as it inhibits creatine breakdown in acidic conditions. There is also no evidence proving CEE or buffered creatines enhance performance and/or creatine retention beyond that of regular creatine monohydrate. Until these issues are resolved, consumer confusion regarding the effectiveness and safety of these products will undermine the industry as a whole. In essence, these issues could undo the strides the industry has gained from one of the most credible and scientifically valid ingredients the sports supplement market has produced.

New Potential for Carnitine
Carnitine is a compound linked to the efficient transport of fatty acids into the muscle mitochondria where they can be used as a fuel source.13 Data suggest L-carnitine supplementation can speed up recovery from exercise stress by reducing lactate production, which decreases muscle soreness post-exercise.14 It has been shown that during intense exercise, sodium-potassium pump function can be inhibited.15 It has also been shown by a research group from the UK that carnitine transport is also linked to the sodium and potassium pump and as such the use of compounds that may accelerate this pump may also enhance carnitine transport during exercise.16^,17

Based on this premise, the development of an ingredient composed of L-carnitine and the patented Vitargo (a glucose polymer) gets carnitine to load into muscle similar to creatine. Currently, the combination of an insulin-mediated transport system for carnitine is patent pending through the University of Nottingham, UK. This breakthrough approach to raise insulin in the blood enhances carnitine storage in muscle, which enhances the muscles' capacity to burn fat. Beyond fat burning, these enhanced carnitine levels also open up provocative potential applications for diabetics by improving the amount of carbohydrates stored in cells independent of eating more carbohydrates. Further research is expected regarding enhancement of endurance and recuperative capacities for athletes.

Co-Q10 Soldiers On
Coenzyme Q10 is a veteran of sports ingredients, though it lacks the sizzle of some of these nouveau products. Co-Q10 is an essential component of the mitochondria, where it plays a major role in energy production.18 In one of the most lauded of human studies with co-Q10 and exercise performance, a 1997 Finnish study of 25 top-level cross-country skiers who took 90mg/day demonstrated significant performance improvements in aerobic, anaerobic and VO2 max indices. Fully 94 per cent of skiers felt that the supplement had improved their performance and recovery time, vs 33 per cent in the placebo group.19

In the same year, a month-long Australian study using similar quantities of supplemental co-Q10 in male road cyclists and triathletes found significant increases in plasma co-Q10 levels, but no correlating improvements in aerobic or anaerobic indices, oxygen uptake, blood-lactate levels, heart rate, lipids, or blood pressure.20 Indeed, in a recent review of 11 studies in which co-Q10 was tested for an effect on exercise capacity, six showed a modest improvement, yet five showed no effect.21

Future Expectations
Over the coming year or so, the sports market will be pushed by predominantly the weight-loss and energy markets, and a shift in general ingredients toward those that have a recognised name, including spices and botanical extracts. This latter shift will be driven by the boomer demographic, which is forever increasing in its movement toward a healthier lifestyle and better bodies.

Looking directly at the raw-ingredients market, a number of ingredients ought to continue to grow and dominate throughout 2007, including the previously discussed beta-alanine, novel testosterone enhancers and, abetted by newly published research, carnitine (notably carnitine combined with an ingredient to boost insulin levels).

The sports-nutrition category will continue to do what it does best — innovate. However, whether this innovation and related fiscal growth continue to occur at the expense of ingredient-safety data, NDI approvals and athlete protection are issues of industry self-regulation.

With meaningful collaboration and debate with governmental (FDA/MHRA) and nongovernmental institutions (University/CRO/Analytical labs), the media negatives reverberating post-BALCO can be overcome.

References
1. No author. Sports nutrition & weight loss report 2006. Nutrition Business Journal. Penton Media, Inc. USA.
2. Begum G, et al. Physiological role of carnosine in contracting muscle. Int J Sport Nutr Exerc Metab 2005;15(5):493-514.
3. Tallon MJ, et al. The carnosine content of vastus lateralis is elevated in resistance-trained bodybuilders. J Strength Cond Res 2005;19(4):725-9.
4. Hill CA, et al. Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity. Amino Acids 2006 (Epub ahead of print).
5. Hoffman J, et al. Effect of creatine and beta-alanine supplementation on performance and endocrine responses in strength/power athletes. Int J Sport Nutr Exerc Metab 2006 Aug;16(4):430-46.
6. Rennie MJ, et al. Branched-chain amino acids as fuels and anabolic signals in human muscle. J Nutr 2006;136(1 Suppl):264S-8S.
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8. Crowe MJ, et al. Effects of dietary leucine supplementation on exercise performance. Eur J Appl Physiol 2006;97(6):664-72.
9. Peptopro study. DSM Food Specialties website. www.dsm.com/en_US/html/dfs/peptopro_recovery_endurance.htm
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11. Campbell B, et al. Pharmacokinetics, safety, and effects on exercise performance of l-arginine alpha-ketoglutarate in trained adult men. Nutrition 2006;22(9):872-81.
12. Lenz H, et al. The creatine kinase system in human skin: protective effects of creatine against oxidative and UV damage in vitro and in vivo. J Invest Dermatol 2005;124(2):443-52.
13. Longo N, et al. Disorders of carnitine transport and the carnitine cycle. Am J Med Genet C Semin Med Genet 2006;142(2):77-85.
14. Brevetti G, et al. Increases in walking distance in patients with peripheral vascular disease treated with L-carnitine: a double-blind, cross-over study. Circulation 1988; 77:767.
15. Sandiford SD, et al. Muscle Na-K-pump and fatigue responses to progressive exercise in normoxia and hypoxia. Am J Physiol Regul Integr Comp Physiol 2005; 289(2):R441-R449.
16. Stephens FB, et al. Insulin stimulates L-carnitine accumulation in human skeletal muscle. FASEB J 2006; 20(2):377-9.
17. Stephens FB, et al. A threshold exists for the stimulatory effect of insulin on plasma L-carnitine clearance in humans. Am J Physiol Endocrinol Metab 2007 Feb;292(2):E637-41.
18. Crane FL. Biochemical functions of coenzyme Q10. J Am Coll Nutr 2001 Dec; 20(6):591-8.
19. Ylikoski T, et al. The effect of coenzyme Q10 on the exercise performance of cross-country skiers. Mol Aspects Med 1997;18 Suppl:S283-90.
20. Weston SB, et al. Does exogenous coenzyme Q10 affect aerobic capacity in endurance athletes? Int J Sport Nutr 1997 Sep; 7(3):197-206.
21. Rosenfeldt F, et al. Systematic review of effect of coenzyme Q10 in physical exercise, hypertension and heart failure. Biofactors 2003;18(1-4):91-100.

Mark J Tallon, PhD, is chief science officer of OxygeniX, a London-based consultancy firm specialising in claims substantiation, product development and technical writing. www.oxygenix.com
Dr Tallon is also co-founder of Cr-Technologies, a raw-ingredients supplier. www.cr-technologies.net Respond: [email protected]