Sports Performance Nutrition
Food and beverages makers face complex challenges when targeting the needs of the active consumer. Many new and re-imagined ingredients are rising to meet those challenges.
Today’s sports nutrition formulations provide sophisticated ingredients, alone and in combination, for not only athletes and weekend warriors -- but also those engaged in the grueling competition of simply getting through the stressful marathon that is modern living. Some of these ingredients stand out for their ergogenic potential in the moment, whereas others require consistent use to build up to the requirements of performance and its improvement.
Sports nutrition ingredients cut across several categories, from proteins, amino acids and carbohydrates to vitamins and minerals, stimulants and other bioactive ingredients that take a more indirect route to help boost a body beyond its routine.
There are many ingredients purported to improve various parameters of athletic performance or body composition. Most have a strong foothold in science; others require more research to better target those who will benefit most from their use, and when and how to take them. In addition, certain ingredients require regular intake in doses that could present a challenge for food and beverage formulation.
For processors developing products for the active consumer, beverages and bars tend to rule. Channels have opened up in chews, gummies and, most recently, flavored gels that are squeezed into the mouth. Convenience, portion control and speedy access are what gym denizens and the casual athlete alike aggressively seek. Flavor still figures large, closely after effectiveness. However, research has indicated that not only can normally undesirable, “medicine-like” flavor notes be tolerated in a sports-oriented product; for many consumers such flavors are taken as a sign of authenticity. It communicates that the product is delivering something beyond mere caloric nourishment.
In other words, a hint of “medicine” flavor can be good; but, more than a hint can kill the product. For this reason, masking flavors, like vanilla or citrus, or fruit concentrates and powders, can be welcome considerations when formulating.
Protein is one of the most popular and versatile sports nutrition ingredients on the market today. Strength and endur-ance athletes need protein to build and repair muscle and to main-tain muscle power. And, when combined with carbohydrate, protein can help replenish glycogen stores more effectively than carbohydrate alone after endurance exercise. In addition, protein is essential throughout the lifespan and can help minimize age-related muscle-mass losses that start at about age 40.
Protein needs are higher for those on a reduced-calorie diet. Ideally, protein should be consumed at regular intervals throughout the day to maximally stimulate muscle protein synthesis, thereby providing multiple opportunities for protein-packed functional foods and beverages.
Companies face a few challenges when manufacturing protein-based products, particularly meeting an efficacious dose in one serving. Also, the product a protein is formulated into can change the bioavailability of the protein’s amino acids, due to conditions or other ingredients that can result in digestive losses and structural changes of amino acids.
Dairy proteins -- whey (hydrolyzed, isolate and concentrate), milk and casein—are the top options for sports nutrition products. Whey reigns because of its amino acid content, digestibility and speed of digestion–factors that make this protein stand out for its ability to spike muscle protein synthesis to a greater extent than soy or casein after a bout of resistance training.
In particular, whey is a protein that is digested quickly, resulting in a rapid appearance of amino acids in the bloodstream. In addition, whey also boasts a higher leucine content than many other proteins. The amino acid leucine is the key amino acid that initiates muscle protein synthesis. Protein quality depends, in part, on total leucine content.
Micellar casein, meanwhile, provides a slow and steady increase in amino acids released into the bloodstream. This helps decrease muscle breakdown and prolongs the rise in muscle protein synthesis (the anabolic period after exercise). Consuming a mix of whey and casein after exercise can be advantageous, particularly for individuals who wait several hours before their next protein-rich meal.
Though dairy proteins are front-runners in the sports nutrition market, egg protein is easy to digest and contains a good amount of leucine (though considerably less than whey protein: 38g of egg whites contains approximately 3g of leucine). Egg protein also is the highest bioavailable protein. It is absorbed more slowly than whey protein, yet does stimulate muscle protein synthesis.
Egg is a good option for consumers who do not want a dairy-based protein. Legume-derived proteins, specifically from soy, peas and, recently, lupin beans, also enjoy high demand -- especially among the growing demographic of vegetarian/vegan consumers.
Flavor-wise, soy protein can develop off-flavor notes in formulation, whereas pea proteins far less so. Any off-flavors from proteins, however, are easily masked -- commonly with vanilla, but also with cocoa or fruit powders/extracts.
Rice protein and sprouted rice protein also have proven to be especially effective forms of vegetarian protein. Rice protein is allergen-free, and sprouting enhances the health benefit. The seed germination leads to positive nutritional changes by creating a complete protein that contains all nine essential amino acids. Moreover, several recent studies have demonstrated that rice protein has similar muscle-building capabilities as whey protein.
Sprouted brown rice protein has a smooth texture, neutral taste, neutral color and neutral aroma. Finished products can avoid taste or texture changes. Sprouted rice protein stays suspended in liquid longer than other rice proteins, making it ideal for beverages, but it also is equally suitable for bars, cereals, and sweet or savory snacks.
Amino Acids, Vitamins and Minerals
Amino acids -- the building blocks of proteins -- are increasingly in demand. Previously the focus of supplements, they’re being used increasingly with sport and energy beverages and, lately, more solid products, such as bars and chews.
The branched-chain amino acids (BCAAs) and leucine are among the most popular, due to their role in stimulating muscle protein synthesis. They also can help decrease soreness and muscle damage resulting from intense exercise. Consumed regularly, immediately before or after resistance training, BCAAs can augment gains in strength and help improve body composition.
Despite the benefits of BCAAs and leucine, there are some hurdles to their use in food or beverage formulations.
“Amino acids do not taste good and are not very soluble,” says Robert Wildman, Ph.D., chief science officer for Dymatize Enterprises LLC. “They have a tendency to rise to the top and float in liquid, so they need to be blended with something like lecithin.”
Instantizing the amino acids and combining them with lecithin can make them a little more soluble. But, getting higher levels of amino acids into beverages can be tricky. Gels are easier to work with, because they are naturally thick. This delivery format has experienced a sudden increase in popularity.
Creatine is one of the most efficacious ergogenic aids in sports. Creatine helps regenerate the high-energy fuel source, adenosine triphosphate (ATP), used during the first several seconds of intense activity -- faster than via anaerobic glycolysis. When consumed regularly over time, creatine can improve measures of strength, power and performance, while also helping to increase lean body mass.
The primary difficulty with creatine formulation comes down to getting an efficacious dose in a product consumers will accept. At least 3g of creatine are needed per serving, according to Wildman. This can be difficult, because creatine is a dry, powdery, gritty, grainy substance that does better in acid environments yet is not very water-soluble. This is why it isn’t typically deployed in ready-to-drink beverages.
Powders are still the main format for creatine, and consumers must mix them thoroughly and consume the product right away. But, Wildman points out, “Chewable supplements are a good avenue for creatine formulation.”
Vitamins and minerals are commonly formulated into sports nutrition products. There is no reported ergogenic benefit from consuming them in conjunction with exercise, but they are vital to the metabolic pathways that keep everything running in the human body. The B-class of vitamins, especially B12, has enjoyed a resurgence of popularity in energy products, leading to “crossover” into those products designed for performance. Electrolyte minerals, particularly sodium and potassium, are the exception, since these are lost through sweat.
To add vitamins and minerals to meet consumer demands, a product developer might want to consider a premix. Working with a supplier to customize a premix that provides necessary balance of components and overages of same will allow the developer to accurately account for the sometimes considerable amount of vitamins lost during processing, as well as uptake barriers secondary to metabolism and competition from other nutrients. In this way, the R&D team can more efficiently (and less expensively) achieve the desired end-product, because waste and manufacturing time are reduced.
Mind and Body Lifts
Caffeine is a go-to favorite for a quick energy hit and mental boost. It can be particularly helpful during long bouts of exhaustive exercise or after sleep deprivation. But, it also happens that, in low-to-moderate doses (3-6mg/kg bodyweight), caffeine is a safe and effective ergogenic aid for both long duration endurance exercise, as well as short, high-intensity exercise (including team sports with intermittent activity). The anhydrous form of caffeine appears to be most bioactively beneficial.
Caffeine has a slightly astringent taste, although the cleaner, more concentrated forms of caffeine are easier to work with. The anhydrous form is perhaps the easiest to use because of its light taste -- barely recognizable once sweetener is added. Dosages also are easier to control with the anhydrous form. Yerba maté or guarana present challenges, in that the exact amount of caffeine might not be immediately obvious to the consumer. The perception among consumers is that the herbal form of caffeine is best, but this is contrary to fact.
Carnitine is found in cells throughout the body and plays an important role in energy production by transporting long-chain fatty acids into the mitochondria of the cell, where they are burned for energy. Carnitine also helps transport toxic compounds out of cells. Given its role in fatty acid oxidation, carnitine supplements often are marketed as “fat-burning” supplements alleged to help the body use more fat for energy, while sparing muscle carbohydrate stores.
Carnitine supplements alone don’t increase muscle carnitine content. Studies have found that carnitine supplementation increases total skeletal muscle carnitine stores, when ingested in combination with carbohydrate. Consuming 80g of a high-molecular-weight glucose polymer increased insulin production, enabling supplemental carnitine (as l-carnitine tartrate, 2g) transport into the mitochondria. This resulted in increased fat use; decreased reliance on carbohydrate as a fuel source during exercise; and increased work output when compared to carbohydrate ingestion alone.
“Individuals need to consider the benefits of this regimen within the context of the potential cost,” cautions Richard Bloomer, Ph.D., chair of the Department of Health and Sport Sciences at The University of Memphis. “That is, some individuals seeking improved exercise performance through dietary supplementation might not want to add 300+ calories per day of high-glycemic carbohydrate to their diet.”
Carnitine is hygroscopic, absorbing water quickly. However, the l-carnitine form is less so. Microencapsulated carnitine protects against water absorption, so it can be formulated in various products, with l-carnitine used in bars and chews, and even gum, although it does have a shorter shelflife.
Coenzyme Q10 (CoQ10) is a vitamin-like, fat-soluble substance synthesized in all cells in healthy humans and found throughout cell membranes. CoQ10 is a co-factor in the production of ATP from carbohydrates and fatty acids, and also acts as an antioxidant, helping counter free-radical damage. Aging and disease states decrease the body’s production of CoQ10, especially after about age 35.
Some studies show CoQ10 may improve exercise performance, while others fail to show a significant benefit. In a double-blind, placebo-controlled, crossover study, adults aged 30-65 receiving 300mg of CoQ10 as ubiquinol daily for four weeks had a significant improvement in blood CoQ10 levels. No improvement was observed in a graded exercise treadmill test (total time @ 29 minutes or less) or repeated cycle sprint test (five 10-second sprints with 2-minute active recovery times in between) compared to placebo.
CoQ10 supplementation increases muscle CoQ10 concentration in both trained and untrained adults. But, in the above study, no significant differences in markers of exercise-induced oxidative stress were noted. Other studies show 90-150mg CoQ10 has no effect on oxidative stress or various measures of athletic performance in both younger and older trained adults. The few studies that show CoQ10 might help decrease measures of fatigue used sedentary adults as study subjects.
It must be noted that CoQ10 needs to be taken over time to replenish depleted stores, however. Supplementation with CoQ10 doesn’t seem to affect endogenous CoQ10 production, when taken over short periods of time (months), nor does it accumulate in the body after cessation of supplementation. CoQ10 supplementation isn’t associated with any serious side effects and has a good safety profile at levels up to 1,200mg/day.
CoQ10 has a high molecular weight and is lipid-soluble, making bioavailability an issue. However, microbead technology and other advancements have enhanced CoQ10 solubility. It is not heat-sensitive (though it is sensitive to light) and doesn’t alter flavors. It can change the color of a product, yet is easily formulated into beverages, gums and bars.
Carbohydrates fuel athletic performance, help rapidly replenish depleted glycogen stores and decrease muscle breakdown after resistance training. And, like protein, there are differences in carbohydrates based on speed of action.
The best carbohydrates for rapidly resynthesizing glycogen and attenuating increases in muscle breakdown after resistance training are those that rapidly spike insulin: dextrose/glucose, maltodextrin and high-molecular-weight glucose polymers. In addition, when formulating carbohydrate-based sports drinks for the endurance athlete, using multiple types of carbohydrate is preferable to a single type.
This is because the body has intestinal transporters for each type of carbohydrate and, when one becomes saturated, the rate of carbohydrate oxidation slows. Therefore, using more than one type of carbohydrate, athletes can absorb more total carbohydrate at one time.
New Kid on the Sports Nutrition Block
Beta-hydroxy-beta-methylbuteric acid (HMB) is a metabolite of the essential amino acid leucine. It can increase muscle protein synthesis, though less effectively than leucine, and also decreases muscle protein breakdown in an insulin-independent manner. Muscle growth, over time, depends on chronically increasing muscle protein synthesis, while also decreasing muscle protein breakdown, particularly right after exercise.
Calcium-HMB is a relatively stable, white crystalline powder that exerts a buffering effect in liquids, making a liquid or emulsion with HMB more resistant to shifts in pH. Calcium-HMB is relatively easy to work with and can be formulated in beverages, bars and powders. The “free acid” form, HMB-fa, is a stable, viscous liquid that mixes readily with water and works well in gel packets, beverages and liquid capsules.
Studies have found supplemental HMB doses of 3g, as well as 0.38 and 0.76mg/kg/day, attenuate muscle breakdown and lower markers of muscle damage after exercise both acutely and over time, enhancing recovery. Although some research indicates that, when taken over time, HMB can increase strength and muscle mass when combined with an effective strength-training program, other studies found no such benefit.
Initially, it appeared as if the elderly and untrained adults stood to gain the greatest ergogenic benefit from HMB, because their potential for muscle damage after resistance training is greater than a trained individual. However, trained adults also can benefit from HMB, if their strength-training program is sufficient in volume and intensity to induce muscle damage.
Future research will help distinguish any differences in muscle breakdown between the two forms of HMB, although at least one study found HMB-fa gel resulted in both faster and greater increases in plasma concentrations of HMB.
Calcium HMB should be consumed at least 1-2 hours prior to a workout, while HMB-fa should be consumed 30-60 minutes beforehand. While 3g is the suggested daily dosage, HMB should be taken in two or three divided doses per day to minimize urinary losses. Also, it could be more effective when consumed for two weeks before an exercise session. HMB appears to be safe for the young and elderly when taken in normal doses (2-3g) over time.
Juicing to Enhance Performance
Beetroot juice and other high-nitrate foods are the latest rage in nitric oxide boosters. High nitrate foods, such as beetroot juice, increase the body’s production of nitrites (as long as bacteria in the mouth that help convert nitrates to nitrites aren’t destroyed with antibiotics or mouthwash). Nitrites, in turn, increase vasodilation, thereby improving blood flow and nutrient delivery to working muscles. When consumed regularly over approximately two weeks, in doses that equate to 300–600mg nitrates, the nitrates can improve time to exhaustion. However, despite the hype, the studies on beetroot juice are not all positive, possibly due to individual variability and study design.