Sports Nutrition: Supplements & Ergogenic Aids

Ergogenic aids are applications or techniques that increase performance capacity work efficiency, and enable easy recovery after exercises or easy adaptation to difficult training. Nutritional support strategies before and during exercise are thought to replenish building block stores, maintain fluid balance, and facilitate regeneration between competitions. The use of ergogenic support can provide an advantage in terms of sportive performance by increasing the ability to perform intermittent high-intensity activity and/or motor skills (Dziedzic & Higham, 2014). Ergogenic supplements are often sold as tablets, capsules, soft gels, liquids, powders, and sticks (Kreider et al., 2010). It is reported that ergogenic nutritional supplements actually increase performance in a very small part, however, they can cause different health problems (Di Luigi, 2008; Maughan, 2005). Using uncontrolled ergogenic nutritional supplements can reduce the bioavailability of many nutrients or the effectiveness of other drugs used (Millen et al., 2004). Athletes turn to sportive nutritional products in order to meet the energy they lose. In this article, information is given about the use of supplements and ergonomic supports and their effects on athlete performance.

Figure 1. Sports nutrition supplement on shelf.

www.123rf.com (n.d.)

Protein powders are ergogenic supplements that are widely used among athletes to increase muscle mass. In particular, casein is thought to have positive effects in long-term resistance exercises. One of the commonly used proteins in sports nutrition is whey protein. Whey protein helps weight loss by reducing appetite and increasing satiety through various mechanisms such as regulation of satiety hormones and hepatic gluconeogenesis (Wirunsawanya et al., 2018). In addition, it has been reported that these protein supplements contribute to the reduction of body weight and total fat mass in overweight and obese patients and to the elimination of cardiovascular risk factors (Wirunsawanya et al., 2018). Studies show that it reduces muscle loss, protects body composition, increases protein synthesis, creates hypertrophy in muscle, repairs muscle damage and increases fat burning (Keri Marshall, 2004; Cooke et al., 2009; Burd et al., 2011; Tsutsumi & Tsutsumi, 2014). Whey protein supplementation helps to repair muscle damage caused by exercise (Buckley et al., 2010). There are studies that predict a positive effect on creatine kinase and blood concentration levels with six-week whey protein supplementation (Philpott et al., 2018). Whey protein supplementation can improve exercise performance in trained men (West et al.,2017).

Sports drinks are products that are produced for the maximum efficiency of the athletes and provide them with benefits in the acute period. For short-term intense workouts, sports drinks can be a good support before and during exercise, while sports drinks can be highly effective for long and intermittent workouts. In addition, it has been emphasized that low-carbohydrate drinks can contribute to performance in order to prevent both the emptying of carbohydrate stores and the loss of fluid-electrolyte in long-term endurance exercises (Coombes, 2000). Sports and energy drinks can be consumed by athletes to replace energy, fluid and electrolytes lost during exercise and to increase performance. However, the composition, active ingredients, effects on sports performance as risk factors of both products are different from each other. When sports drinks are used and are correctly adjusted to the type of sport and the individual, they help to significantly improve physical performance due to their carbohydrate, electrolyte and fluid contents. It has been reported that drinking protein-containing sports drinks during exercise increases endurance, reduces dehydration-induced weight loss, and supports reducing muscle damage after exercise compared to those containing only carbohydrates and electrolytes (Naclerio, 2014). Sports drinks contain different types of carbohydrates (sucrose, fructose, glucose polymers, glucose) and they consist of colorant, and electrolytes. At the same time, if they contain 6-8% glucose and sucrose, they are absorbed as fast as water in the body, and they also provide energy to the working muscles. Since those with a carbohydrate ratio of 6-10% are quickly absorbed and mixed with the blood, they are recommended to be used during activity. Those with a carbohydrate ratio of 10-25% can be used during rest, since absorption is completed in a longer time. In addition, drinks containing more than 10% carbohydrates can cause nausea, diarrhea and cramps in some individuals. This may be due to increased insulin sensitivity after exercise. Sports drinks also contain sodium and potassium electrolytes. Drinks containing sodium trigger the thirst mechanism and encourage fluid intake. Sodium also improves absorption and retention. It also helps athletes who sweat excessively and salty to replenish salt. While the drinks containing sodium do not isolate the feeling of thirst, the ones that do not (including drinking water) cause a decrease in the desire to drink water and, consequently, insufficient fluid intake, as it isolates thirst. When glucose and sodium are added to water, fluid absorption is accelerated because glucose and sodium accelerate osmosis (Naclerio, 2014). Despite strategies that may be effective, improper use can lead to diabetes and tooth decay, and if they contain more potassium and calcium than is lost through sweat, they can put pressure on skeletal and cardiac muscles during exertion and cause pulse irregularities. In addition, these sugar-containing fluids can cause problems due to the displacement of blood for the digestion of sugar during strenuous exercise, insufficient blood flow to other organs, and consequent cramping and increased temperature (Naclerio, 2014). With the use of glutamine in endurance sports, there was a decrease in the incidence of disease reported after exercise (Castell, 1996).

Figure 2: Studies Show Little Benefit in Supplements. Paul Rogers (2016).

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BCAA (leucine, isoleucine, valine) is an essential amino acid for protein synthesis (Dudgeon et al., 2016; Platt et al., 2016). BCAAs are found in high amounts in skeletal muscle, where are also oxidized, while other amino acids are predominantly catabolized in the liver. They help prevent protein breakdown and increase protein synthesis. Many studies have shown that BCAAs reduce muscle soreness and muscle damage during exercise, but also play a key role in recovery. Such an ingredient preserves muscle mass when protein loss and catabolism occur, and helps to reduce muscle damage and accelerate recovery after heavy endurance training. They are also important for maintaining the normal functioning of body performance and ideal body composition (Dudgeon et al., 2016; Shimomura, 2004). According to studies, it has been shown that taking BCAAs before and after exercise has positive effects on reducing exercise-induced muscle damage and increasing muscle protein synthesis (Howatson et al., 2012). Muscle damage causes delayed muscle soreness that occurs 24-48 hours after intense exercise and inhibits athletic performance. Other studies have shown that BCAA supplementation improves plasma glutamine concentration as well as mononuclear cell proliferation in peripheral blood in response to mitogens after prolonged intense exercise. By directing the lymphocyte immune response towards Th1, BCAAs change the cytokine production sequence released by exercise (Bassit et al., 2002). In line with these findings, BCAAs can be considered as a useful supplement because of their positive effects on muscle recovery and immune regulation (Bassit et al., 2002; Negro et al., 2008). In addition to BCAA's, ZMA supplements can aid muscle growth by enhancing athletic performance; especially in people with zinc or magnesium deficiency, they can provide this increase more clearly. ZMA is a supplement consisting of Zinc, Vitamin B6 and Magnesium. It can strengthen their anabolic hormonal profile, affect and slow down the catabolic process, strengthen the immune level and improve adaptation to resistance exercises. Because of these features, it is preferred by athletes (Wilborn et al., 2004).

Caffeine and creatine are two of the most commonly employed ergogenic aids. Studies have shown that creatine increases strength, power output, sprint performance, total work to fatigue, peak power, and peak power exhibited during multiple sets of maximal effort contractions (Liddle & Connor, 2013). In a study conducted with cyclists, it was shown that creatine supplementation decreased blood lactate levels and increased the lactate threshold (Oliver et al.,2013). Creatine is predicted to be effective in repetitive short bursts of power between 6 seconds and 4 minutes, mainly sprinting and weight lifting, high-intensity activity (Terjung et al., 2000; Branch & Williams, 2002; Branch, 2003; Insel et al., 2004; Burke, 2006; Dunford, 2006). There are studies on the potential ergogenic effects of caffeine, the mobilizing of free fatty acids, and its role in sparing of muscle glycogen (Dunford, 2006; Graham & Moisey, 2005). Caffeine is known to be a powerful ergogenic aid. It has also been widely suggested to increase exercise capacity by promoting fat oxidation and inhibiting carbohydrate oxidation through feedback mechanisms in active muscle (Tarnopolsky 1994; Graham 2001). It has been suggested that this action results in reduced dependence on muscle glycogen stores, and glycogen subsequently promotes increased endurance. This theory was supported by Costill et al. (Costill et al. 1978; Ivy et al. 1979; Essig et al. 1980).

Figure 3: Carnitine. Donato, (2021).

www.mskcc.org

Carnitine is present in sufficient amount in muscle cells. In other words, it can be said that a situation such as carnitine deficiency will not occur. Much more can be obtained from the diet than the carnitine excreted in the urine. The body also stores excess carnitine. It can be said that in a healthy body (including professional athletes) there is no carnitine problem and it finds enough carnitine. When carnitine is taken orally, only the rate of carnitine in the blood increases, it does not reach the muscles and is excreted from the body with urine. L-carnitine is required for the transport of long-chain fatty acids from the cytosol to the mitochondrial matrix. ATP is produced by the oxidation of long-chain fatty acids in the mitochondrial matrix. L-carnitine is thought to play a key role in muscle energy metabolism by increasing fatty acid oxidation and energy expenditure. There are studies indicating that L-carnitine improves endurance capacity by increasing oxygen uptake or fatty acid oxidation (Pandareesh & Anand, 2013).

Figure 4: What's Really in Supplements? Mark Matcho, (2009).

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Phosphate salts are one of the basic elements to be taken in the human body and are important for both nutrition and other functions of the body. Since it cannot be synthesized in the body, it must be taken from the outside through food. To date, few studies have supported the benefits of phosphate salt supplementation on exercise performance. In these studies, maximum oxygen consumption (Kreider et al., 1992; Czuba et al., 2009) and increase in anaerobic threshold (Kreider et al., 1992), time trial performance (Brewer et al., 2015) and improvement in repeated sprint ability (Buck et al. ., 2015; Kopec et al., 2016) and a number of mechanisms have been proposed to explain the ergogenic effects of phosphate loading, including increased oxidative metabolism and increased ATP synthesis, faster restoration of ATP and phosphocreatine in muscles. Phosphate supplementation was predicted to positively affect the cardiorespiratory system and gross efficiency in elite cyclists in a hypoxic environment. Sodium salts can be used to eliminate the effect of lactic acid, which is produced in the organism by the use of glycogen in an anaerobic environment and accumulates in the muscles according to the action mechanisms of the buffering systems. Specifically, sodium bicarbonate buffers anaerobic exercises to reduce the oxidant effect on muscle tissue (Lindh et al., 2008).

Figure 5: Hepatitis C Drugs Boost Remdesivir’s Antiviral Activity Against COVID-19. Jenna Luecke (2021).

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Apart from performance, various supplements may also be effective in preventing certain diseases (Klein, 2011). Caffeine is widely used in sports as a performance-enhancing or ergogenic supplement, often in the form of caffeinated tablets, gels, or chewables. The ergogenic effects of caffeine on exercise performance are generally explained by its ability to bind to adenosine receptors. Caffeine metabolic rate varies between individuals depending on genetic variations (Pickering & Kiely, 2018). Apart from this, related to athlete performance, short-term folate supplementation in aerobic exercise is predicted to strengthen the immune system and reduce cardiovascular risk. It is thought to be applicable as a short-term ergogenic supplement due to the low cost of folate (Grigoletti et al., 2018). As another ergonomic support, athletes use ginseng to increase aerobic performance and energy level. Its possible mechanism of action is that it increases the response to cortisol during strenuous sports and decreases lactic acid production by keeping creatine phosphate levels high in the body. It is also known that ginseng has anti-inflammatory, antioxidant, stimulating brain function and performance enhancing effects (Sellami et al., 2018). It has been determined that ginseng increases muscle stimulation and muscle strength in athletes, and accelerates the healing of muscle damage (Cristina-Souza et al., 2022). In addition, ginseng supplementation positively affects bodybuilders' anabolic indices, muscle strength and body composition (Azizi & Moradi, 2021).

In summary, maintaining health and achieving high sportive performance can only be achieved through balanced, regular and purposeful nutrition. A well-structured, periodic training program tailored to the athlete's goal, an appropriate nutrition plan, and the right balance between exercise and recovery are essential to achieving personal athletic goals. However, the correct use of supplements is very important to increase performance, balance body fat ratio and activate protein synthesis. Ergogenic aids can be used to continuously increase strength, endurance, speed and dexterity.

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Figure 1: Anonymous, (n.d.). Sports nutrition supplement on shelf. [Photo]. Retrieved from https://www.123rf.com/photo_126028588_sports-nutrition-supplement-on-shelf-fitness-protein-shakers-energy-drinks-vector-illustration-healt.html?vti=n92d7mm723x1fhni5q-1-6

Figure 2: Rogers, P. (2016). Studies Show Little Benefit in Supplements. The New York Times. [Photo]. Retrieved from https://www.nytimes.com/2016/11/15/well/eat/studies-show-little-benefit-in-supplements.html

Figure 3: Donato (2021). Carnitine. Memorial Sloan Kettering Cancer Center. [Photo]. Retrieved from

https://www.mskcc.org/cancer-care/integrative-medicine/herbs/carnitine

Figure 4: Matcho, M. (2009). What's Really in Supplements? The Wall Street Journal. [Photo]. Retrieved from https://www.wsj.com/articles/SB10001424052970204731804574390840811949538

Figure 5: Luecke J., (2021). Hepatitis C Drugs Boost Remdesivir’s Antiviral Activity Against COVID-19. [Photo]. Retrieved from https://news.utexas.edu/2021/04/27/hepatitis-c-drugs-boost-remdesivirs-antiviral-activity-against-covid-19/