Bodybuilding supplement

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Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. Bodybuilding supplements may contain ingredients that are advertised to increase a person's muscle, body weight, athletic performance, and decrease a person's percent body fat for desired muscle definition. Among the most widely used are high protein drinks, pre-workout blends, branched-chain amino acids (BCAA), glutamine, arginine, essential fatty acids, creatine, HMB, whey protein, ZMA, and weight loss products. [1] [2] Supplements are sold either as single ingredient preparations or in the form of "stacks" – proprietary blends of various supplements marketed as offering synergistic advantages.

Contents

History

Athletes in ancient Greece were advised to consume large quantities of meat and wine. A number of herbal concoctions and tonics have been used by strong men and athletes since ancient times across cultures to try to increase their strength and stamina. [3]

In the 1910s, Eugen Sandow, widely considered to be the first modern bodybuilder in the West, advocated the use of dietary control to enhance muscle growth. Later, bodybuilder Earle Liederman advocated the use of "beef juice" or "beef extract" (basically, consommé) as a way to enhance muscle recovery. In the 1950s, with recreational and competitive bodybuilding becoming increasingly popular, Irvin P. Johnson began to popularize and market egg-based protein powders marketed specifically at bodybuilders and physical athletes. The 1970s and 1980s marked a dramatic increase in the growth of the bodybuilding supplement industry, fueled by the widespread use of modern marketing techniques and a marked increase in recreational bodybuilding.

In October 1994, the Dietary Supplement Health and Education Act (DSHEA) was signed into law in the USA. Under DSHEA, responsibility for determining the safety of the dietary supplements changed from the government to the manufacturer, and supplements no longer required approval from the U.S. Food and Drug Administration (FDA) before distributing the products. Since that time, manufacturers did not have to provide FDA with the evidence to substantiate safety or effectiveness unless a new dietary ingredient was added. It is widely believed that the 1994 DSHEA further consolidated the position of the supplement industry and lead to additional product sales. [4]

Protein

Protein shakes, made from protein powder (center) and milk (left), are a common bodybuilding supplement. Protein shake.jpg
Protein shakes, made from protein powder (center) and milk (left), are a common bodybuilding supplement.

Bodybuilders may supplement their diets with protein for reasons of convenience, lower cost (relative to meat and fish products), ease of preparation, and to avoid the concurrent consumption of carbohydrates and fats. Additionally, some argue that bodybuilders, by virtue of their unique training and goals, require higher-than-average quantities of protein to support maximal muscle growth. [5] [6] [7] [8] [9] [10] [11] [12] While the recommended dietary allowance is much less, [13] Harvard Medical School points out in Health Health Publishing that this RDA (recommended daily allowance) is “the minimum amount you need to keep from getting sick — not the specific amount you are supposed to eat every day.” [14] Protein supplements are sold in ready-to-drink health shakes, bars, meal replacement products (see below), bites, oats, gels and powders. Protein powders are the most popular and may have flavoring added for palatability. The powder is usually mixed with water, milk or fruit juice and is generally consumed immediately before and after exercising or in place of a meal. The sources of protein are as follows and differ in protein quality depending on their amino acid profile and digestibility:

Shaker Bottle commonly used to mix supplements. Often has mesh or a metal whisk inside to breakdown lumps in the mixture. Osaka protein shaker.jpg
Shaker Bottle commonly used to mix supplements. Often has mesh or a metal whisk inside to breakdown lumps in the mixture.

Some nutritionists have suggested that higher calcium excretion may be due to a corresponding increase in protein-induced calcium absorption in the intestines. [16] [17] [18]

Amino acids

Some bodybuilders believe that amino acid supplements may benefit muscle development, but consumption of such supplements is unnecessary in a diet that already includes adequate protein intake. [19]

Prohormones

An androgen prohormone, or proandrogen, is a prohormone (or prodrug) of an anabolic-androgenic steroid (AAS). They can be prohormones of testosterone or of synthetic AAS, for example, nandrolone (19-nortestosterone). Dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and androstenedione may all be considered proandrogens of testosterone. [20]

Since 2005, the use of steroid precursors (prohormones) has been illegal in the U.S. [21]

Creatine

Creatine is an organic acid naturally occurring in the body (and in red meats) [22] that supplies energy to muscle cells for short bursts of energy (as required in lifting weights) via creatine phosphate replenishment of ATP. Scientific studies have shown that creatine supplementation can increase the consumer's strength, [23] energy during performance, [24] muscle mass, and recovery times after exercise. In addition, recent studies have also shown that creatine improves brain function. [25] and reduces mental fatigue. [26]

Some studies have suggested that consumption of creatine with protein and carbohydrates can have a greater effect than creatine combined with either protein or carbohydrates alone. [27]

While generally considered safe, long-term or excessive consumption of creatine may have an adverse effect on the kidneys, liver, or heart and should be avoided if any pre-existing conditions affecting these organs exist. [28]

β-Hydroxy β-methylbutyrate

When combined with an appropriate exercise program, dietary supplementation with β-hydroxy β-methylbutyrate (HMB) has been shown to dose-dependently augment gains in muscle hypertrophy (i.e., the size of a muscle), [29] [30] muscle strength, [29] [31] [32] and lean body mass, [29] [31] [32] reduce exercise-induced skeletal muscle damage, [note 1] [29] [30] [32] and expedite recovery from high-intensity exercise. [29] [33] HMB is believed to produce these effects by increasing muscle protein synthesis and decreasing muscle protein breakdown by various mechanisms, including activation of the mechanistic target of rapamycin (mTOR) and inhibition of the proteasome in skeletal muscles. [31] [34]

The inhibition of exercise-induced skeletal muscle damage by HMB is affected by the time that it is used relative to exercise. [29] [33] The greatest reduction in skeletal muscle damage from a single bout of exercise appears to occur when calcium HMB is ingested 1–2 hours prior to exercise. [33]

Controversy

Mislabeling and adulteration

While many of the claims are based on scientifically-based physiological or biochemical processes, their use in bodybuilding parlance is often heavily colored by bodybuilding lore and industry marketing and, as such, may deviate considerably from traditional scientific usages of the terms. In addition, ingredients listed have been found at times to be different from the contents. In 2015, Consumer Reports reported unsafe levels of arsenic, cadmium, lead, and mercury in several of the protein powders that were tested. [35]

In the United States, the manufacturers of dietary supplements do not need to provide the Food and Drug Administration with evidence of product safety prior to marketing. [36] As a result, the incidence of products adulterated with illegal ingredients has continued to rise. [36] In 2013, one-third of the supplements tested were adulterated with unlisted steroids. [37] More recently, the prevalence of designer steroids with unknown safety and pharmacological effects has increased. [38] [39]

In 2015, a CBC investigative report found that protein spiking (i.e., the addition of amino-acid filler to manipulate analysis) was not uncommon; [40] however, many of the companies involved challenged these claims. [40]

Health problems

The US FDA reports 50,000 health problems a year due to dietary supplements [41] and these often involve bodybuilding supplements. [42] For example, the "natural" best-seller Craze, 2012's "New Supplement of the Year" by bodybuilding.com, widely sold in stores such as Walmart and Amazon, was found to contain N,alpha-Diethylphenylethylamine, a methamphetamine analog. [43]

The incidence of liver damage from herbal and dietary supplements is about 16–20% of all supplement products causing injury, with the occurrence growing globally over the early 21st century. [2] The most common liver injuries from weight loss and bodybuilding supplements involve hepatocellular damage and jaundice. The most common supplement ingredients attributed to these injuries are catechins from green tea, anabolic steroids, and the herbal extract, aegeline. [2] Other products by supplement designer and CEO of Driven Sports, Matt Cahill, have contained dangerous substances causing blindness or liver damage, and his pre-workout supplement Craze was found to contain illegal stimulants [44] that resulted in several athletes failing drug tests. [45]

Protein effectiveness

Some have argued that there is little evidence to indicate any benefit to using bodybuilding protein or amino acid supplements. A 2005 overview concluded that "[i]n view of the lack of compelling evidence to the contrary, no additional dietary protein is suggested for healthy adults undertaking resistance or endurance exercise". [13]

In contrast, a 2018 systematic review, meta-analysis and meta-regression concluded that, “Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults.“ (RET is an abbreviation for resistance exercise training.) [46]

See also

Notes

  1. ↑ The effect of HMB on skeletal muscle damage has been assessed in studies using four different biomarkers of muscle damage or protein breakdown: serum creatine kinase, serum lactate dehydrogenase, urinary urea nitrogen, and urinary 3-methylhistidine. [29] [32] [33] When exercise intensity and volume are sufficient to cause skeletal muscle damage, such as during long-distance running or progressive overload, HMB supplementation has been demonstrated to attenuate the rise in these biomarkers by 20–60%. [29] [33]

Related Research Articles

<span class="mw-page-title-main">Bodybuilding</span> Control and development of musculature

Bodybuilding is the practice of progressive resistance exercise to build, control, and develop one's muscles via hypertrophy. An individual who engages in this activity is referred to as a bodybuilder. It is primarily undertaken for aesthetic purposes over functional ones, distinguishing it from similar activities such as powerlifting and calisthenics.

<span class="mw-page-title-main">Leucine</span> Chemical compound

Leucine (symbol Leu or L) is an essential amino acid that is used in the biosynthesis of proteins. Leucine is an α-amino acid, meaning it contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isobutyl group, making it a non-polar aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it: it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, and beans and other legumes. It is encoded by the codons UUA, UUG, CUU, CUC, CUA, and CUG. Leucine is named after the Greek word for "white": λευκός (leukós, "white"), after its common appearance as a white powder, a property it shares with many other amino acids.

<span class="mw-page-title-main">Ornithine</span> Chemical compound

Ornithine is a non-proteinogenic α-amino acid that plays a role in the urea cycle. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. The radical is ornithyl.

<span class="mw-page-title-main">Dietary supplement</span> Product providing additional nutrients

A dietary supplement is a manufactured product intended to supplement a person's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources, or that are synthetic. The classes of nutrient compounds in supplements include vitamins, minerals, fiber, fatty acids, and amino acids. Dietary supplements can also contain substances that have not been confirmed as being essential to life, and so are not nutrients per se, but are marketed as having a beneficial biological effect, such as plant pigments or polyphenols. Animals can also be a source of supplement ingredients, such as collagen from chickens or fish for example. These are also sold individually and in combination, and may be combined with nutrient ingredients. The European Commission has also established harmonized rules to help insure that food supplements are safe and appropriately labeled.

<span class="mw-page-title-main">Whey</span> Liquid remaining after milk has been curdled and strained

Whey is the liquid remaining after milk has been curdled and strained. It is a byproduct of the manufacturing of cheese or casein and has several commercial uses. Sweet whey is a byproduct resulting from the manufacture of rennet types of hard cheese, like cheddar or Swiss cheese. Acid whey is a byproduct brought out during the making of acid types of dairy products, such as strained yogurt.

<span class="mw-page-title-main">Cachexia</span> Syndrome causing muscle loss not entirely reversible

Cachexia is a complex syndrome associated with an underlying illness, causing ongoing muscle loss that is not entirely reversed with nutritional supplementation. A range of diseases can cause cachexia, most commonly cancer, congestive heart failure, chronic obstructive pulmonary disease, chronic kidney disease, and AIDS. Systemic inflammation from these conditions can cause detrimental changes to metabolism and body composition. In contrast to weight loss from inadequate caloric intake, cachexia causes mostly muscle loss instead of fat loss. Diagnosis of cachexia can be difficult due to the lack of well-established diagnostic criteria. Cachexia can improve with treatment of the underlying illness but other treatment approaches have limited benefit. Cachexia is associated with increased mortality and poor quality of life.

<span class="mw-page-title-main">Creatine</span> Chemical compound

Creatine is an organic compound with the nominal formula (H2N)(HN)CN(CH3)CH2CO2H. It exists in various tautomers in solutions. Creatine is found in vertebrates, where it facilitates recycling of adenosine triphosphate (ATP), primarily in muscle and brain tissue. Recycling is achieved by converting adenosine diphosphate (ADP) back to ATP via donation of phosphate groups. Creatine also acts as a buffer.

<span class="mw-page-title-main">Carnosine</span> Chemical compound

Carnosine (beta-alanyl-L-histidine) is a dipeptide molecule, made up of the amino acids beta-alanine and histidine. It is highly concentrated in muscle and brain tissues. Carnosine was discovered by Russian chemist Vladimir Gulevich.

<span class="mw-page-title-main">Whey protein</span> Protein supplement

Whey protein is a mixture of proteins isolated from whey, the liquid material created as a by-product of cheese production. The proteins consist of α-lactalbumin, β-lactoglobulin, serum albumin and immunoglobulins. Glycomacropeptide also makes up the third largest component but is not a protein. Whey protein is commonly marketed as a protein supplement, and various health claims have been attributed to it. A review published in 2010 in the European Food Safety Authority Journal concluded that the provided literature did not adequately support the proposed claims.

β-Hydroxy β-methylbutyric acid Chemical compound

β-Hydroxy β-methylbutyric acid (HMB), otherwise known as its conjugate base, β-hydroxyβ-methylbutyrate, is a naturally produced substance in humans that is used as a dietary supplement and as an ingredient in certain medical foods that are intended to promote wound healing and provide nutritional support for people with muscle wasting due to cancer or HIV/AIDS. In healthy adults, supplementation with HMB has been shown to increase exercise-induced gains in muscle size, muscle strength, and lean body mass, reduce skeletal muscle damage from exercise, improve aerobic exercise performance, and expedite recovery from exercise. Medical reviews and meta-analyses indicate that HMB supplementation also helps to preserve or increase lean body mass and muscle strength in individuals experiencing age-related muscle loss. HMB produces these effects in part by stimulating the production of proteins and inhibiting the breakdown of proteins in muscle tissue. No adverse effects from long-term use as a dietary supplement in adults have been found.

<span class="mw-page-title-main">Sarcopenia</span> Muscle loss due to ageing or immobility

Sarcopenia is a type of muscle loss that occurs with aging and/or immobility. It is characterized by the degenerative loss of skeletal muscle mass, quality, and strength. The rate of muscle loss is dependent on exercise level, co-morbidities, nutrition and other factors. The muscle loss is related to changes in muscle synthesis signalling pathways. It is distinct from cachexia, in which muscle is degraded through cytokine-mediated degradation, although the two conditions may co-exist. Sarcopenia is considered a component of frailty syndrome. Sarcopenia can lead to reduced quality of life, falls, fracture, and disability.

<span class="mw-page-title-main">Branched-chain amino acid</span> Amino acid with a branched carbon chain

A branched-chain amino acid (BCAA) is an amino acid having an aliphatic side-chain with a branch. Among the proteinogenic amino acids, there are three BCAAs: leucine, isoleucine, and valine. Non-proteinogenic BCAAs include 2-aminoisobutyric acid and alloisoleucine.

<span class="mw-page-title-main">Protein supplement</span>

A protein supplement is a dietary supplement or a bodybuilding supplement, and usually comes in the form of a protein bar, protein powder, and even readily available as a protein shake. Usually made from whey, plant, and/or meat sources.

<span class="mw-page-title-main">Muscle atrophy</span> Loss of skeletal muscle mass

Muscle atrophy is the loss of skeletal muscle mass. It can be caused by immobility, aging, malnutrition, medications, or a wide range of injuries or diseases that impact the musculoskeletal or nervous system. Muscle atrophy leads to muscle weakness and causes disability.

<span class="mw-page-title-main">Sports nutrition</span> Study and practice of nutrition to improve performance

Sports nutrition is the study and practice of nutrition and diet with regards to improving anyone's athletic performance. Nutrition is an important part of many sports training regimens, being popular in strength sports and endurance sports. Sports nutrition focuses its studies on the type, as well as the quantity of fluids and food taken by an athlete. In addition, it deals with the consumption of nutrients such as vitamins, minerals, supplements and organic substances that include carbohydrates, proteins and fats.

<span class="mw-page-title-main">Protein (nutrient)</span> Nutrient for the human body

Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue and can also serve as a fuel source. As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal per gram; in contrast, lipids provide 9 kcal per gram. The most important aspect and defining characteristic of protein from a nutritional standpoint is its amino acid composition.

<span class="mw-page-title-main">Muscle hypertrophy</span> Enlargement or overgrowth of a muscle organ

Muscle hypertrophy or muscle building involves a hypertrophy or increase in size of skeletal muscle through a growth in size of its component cells. Two factors contribute to hypertrophy: sarcoplasmic hypertrophy, which focuses more on increased muscle glycogen storage; and myofibrillar hypertrophy, which focuses more on increased myofibril size. It is the primary focus of bodybuilding-related activities.

Arginine alpha-ketoglutarate (AAKG) is a salt of the amino acid arginine and alpha-ketoglutaric acid. It is marketed as a bodybuilding supplement.

α-Ketoisocaproic acid Chemical compound

α-Ketoisocaproic acid (α-KIC), also known as 4-methyl-2-oxovaleric acid, and its conjugate base and carboxylate, α-ketoisocaproate, are metabolic intermediates in the metabolic pathway for L-leucine. Leucine is an essential amino acid, and its degradation is critical for many biological duties. α-KIC is produced in one of the first steps of the pathway by branched-chain amino acid aminotransferase by transferring the amine on L-leucine onto alpha ketoglutarate, and replacing that amine with a ketone. The degradation of L-leucine in the muscle to this compound allows for the production of the amino acids alanine and glutamate as well. In the liver, α-KIC can be converted to a vast number of compounds depending on the enzymes and cofactors present, including cholesterol, acetyl-CoA, isovaleryl-CoA, and other biological molecules. Isovaleryl-CoA is the main compound synthesized from ɑ-KIC. α-KIC is a key metabolite present in the urine of people with Maple syrup urine disease, along with other branched-chain amino acids. Derivatives of α-KIC have been studied in humans for their ability to improve physical performance during anaerobic exercise as a supplemental bridge between short-term and long-term exercise supplements. These studies show that α-KIC does not achieve this goal without other ergogenicsupplements present as well. α-KIC has also been observed to reduce skeletal muscle damage after eccentrically biased resistance exercises in people who do not usually perform those exercises.

Pre-workout is a generic term for a range of bodybuilding supplement products used by athletes and weightlifters to enhance athletic performance. Supplements are taken to increase endurance, energy, and focus during a workout. Pre-workout supplements contain a variety of ingredients such as caffeine and creatine, differing by capsule or powder products. The first pre-workout product entered the market in 1982, and since then the category has grown in use. Some pre-workout products contain ingredients linked to adverse effects. Although these products are not regulated, the Food and Drug Administration (FDA) warns consumers to be cautious when consuming them.

References

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  29. 1 2 3 4 5 6 7 8 Momaya A, Fawal M, Estes R (April 2015). "Performance-enhancing substances in sports: a review of the literature". Sports Medicine. 45 (4): 517–31. doi:10.1007/s40279-015-0308-9. PMID   25663250. S2CID   45124293. Wilson et al. [91] demonstrated that when non-resistance trained males received HMB pre-exercise, the rise of lactate dehydrogenase (LDH) levels reduced, and HMB tended to decrease soreness. Knitter et al. [92] showed a decrease in LDH and creatine phosphokinase (CPK), a byproduct of muscle breakdown, by HMB after a prolonged run. ... The utility of HMB does seem to be affected by timing of intake prior to workouts and dosage [97].
  30. 1 2 Wu H, Xia Y, Jiang J, Du H, Guo X, Liu X, et al. (September 2015). "Effect of beta-hydroxy-beta-methylbutyrate supplementation on muscle loss in older adults: a systematic review and meta-analysis". Archives of Gerontology and Geriatrics. 61 (2): 168–75. doi:10.1016/j.archger.2015.06.020. PMID   26169182.
  31. 1 2 3 Brioche T, Pagano AF, Py G, Chopard A (August 2016). "Muscle wasting and aging: Experimental models, fatty infiltrations, and prevention" (PDF). Molecular Aspects of Medicine. 50: 56–87. doi:10.1016/j.mam.2016.04.006. PMID   27106402. S2CID   29717535. Archived (PDF) from the original on 2021-11-24. Retrieved 2020-09-01. In conclusion, HMB treatment clearly appears to be a safe potent strategy against sarcopenia, and more generally against muscle wasting, because HMB improves muscle mass, muscle strength, and physical performance. It seems that HMB is able to act on three of the four major mechanisms involved in muscle deconditioning (protein turnover, apoptosis, and the regenerative process), whereas it is hypothesized to strongly affect the fourth (mitochondrial dynamics and functions). Moreover, HMB is cheap (~30– 50 US dollars per month at 3 g per day) and may prevent osteopenia (Bruckbauer and Zemel, 2013; Tatara, 2009; Tatara et al., 2007, 2008, 2012) and decrease cardiovascular risks (Nissen et al., 2000). For all these reasons, HMB should be routinely used in muscle-wasting conditions especially in aged people. ... 3 g of CaHMB taken three times a day (1 g each time) is the optimal posology, which allows for continual bioavailability of HMB in the body (Wilson et al., 2013).
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