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In this research paper I will be discussing the ever-popular athletic supplements: Creatine, Androstenedione, and HMB. It has been proven that these supplements when taken in the proper doses will produce phenomenal results in athletic performance. They are taken by athletes of all fields of play in order too give them that extra edge over competition.
Creatine monohydrate, which is the number one supplement preferred by athletes, is not a mineral, herb, or steroid. Creatine is a natural nutrient found in the human body and the bodies of most animals. Creatine is also consumed in certain foods, particularly meats and fish, 2.4lbs of uncooked steak contains about four to five grams of Creatine (2). However, some of the Creatine is degraded during the cooking process. The average person consumes about one gram of Creatine a day from a regular diet. (3)
Creatine is also produced endogenously by the liver, pancreas and kidneys. The body of a 70-kg individual produces about two grams of Creatine a day consisting a turnover rate of about 1.6% a day. The body of a 70-kg individual would contain a total of about 120 grams of Creatine. Approximately 60% of the Creatine is stored in its phosphorylated form, phosphocreatine also known as Creatine phosphate(1).
Approximately 95% of the body?s Creatine supply are found in the skeletal muscles. The remaining 5% are scattered throughout the rest of the body, with the highest concentrations in the heart, brains, and testes. A skeletal muscle itself does not produce Creatine, but utilizes the Creatine originating in the liver and kidneys. The human body gets most of the Creatine; it needs from food or dietary supplements. Creatine is easily absorbed from the intestinal tract into the blood stream. When dietary consumption is inadequate to meet the body?s needs, a limited supply can be synthesized from the amino acids arginine, glycine, and methionine. This Creatine production occurs in the liver, pancreas, and kidneys.
Creatine monohydrate is an essential part of the primary energy source used for muscle contraction. It exists in two different forms, one as a free (chemically unbound) Creatine and the other a Creatine phosphate, which makes up 2/3?s of the body?s total Creatine supply. When your muscles contract, the initial fuel for this movement is a compound called ATP (andenosine triphosphat). As the muscles keep contracting the ATP release one of it?s molecules, thus becoming a different compound called ADP. ATP provides energy for about ten seconds, so for muscle contraction to continue, more ATP must be produced. ADP causes your muscles to fatigue. Creatine phosphate comes to the rescue by giving up its phosphate molecule to ADP, recreating ATP. This ATP can then be burned again as fuel for more muscle contraction. The primary purpose of phosphocreatine is to re-supply ADP with high-energy phosphates to buffer levels of ATP when ATP levels are falling rapidly as in intense exercise. ATP is the only direct source of energy that can be used by the cells. Glucose and free fatty acids are metabolized to eventually produce ATP, which the cell utilizes to do work such as muscular contraction. Skeletal muscle fatigues if ATP levels fall below 25-30% (ATP levels can not fall below 70%)(3). Creatine phosphate then acts as a reserve of high-energy phosphates. It transfers its phosphates to ADP to regenerate ATP while the glycolytic pathway is still ?warming-up?. Indeed it has been shown in studies that phosphocreatine usage peaks within a third of the time it takes for glycolysis to peak (which takes three seconds)(2). There is also a 3-to-1 ratio of phosphocreatine to ATP this allows ATP to be regenerated from ADP at a faster rate than the ATP is depleted (3).
The bottom line is that your ability to regenerate ATP depends on your supply of Creatine. The more Creatine monohydrate available, the more ATP synthesis occurs, which allows you to train your muscles to their maximum potential. This greater ATP synthesis also keeps your body form relying on the other energy system called glycolysis, which has lactic acid as a by product. This lactic acid creates the burning sensation you feel during intense exercise. If the amount of acid becomes to great, muscle movement stops. But if you keep on using ATP because of all the Creatine you have, you can minimize the amount of lactic acid produced and actually exercise longer and harder. This helps you gain strength, power, and muscle size, and you won?t get fatigued as easily. Creatine has also been thought to enhance your body?s ability to make proteins. Creatine is also thought to help absorb intracellular water into muscle cells by bloating the muscles with Creatine rich fluid, thus resulting in higher muscle volume. This allows for greater leverage and requires the muscles to move less and lift more weight. Creatine pulls water from other parts of the body to perform its work in cell volumization of the muscle.
Creatine helps athletes in many fields of play. Creatine users claim it to have many advantages, such as increased endurance, increased overall work potential, increased speed of muscular action, and potential to further increase muscle mass. Many tests subjects participating in Creatine supplementation experiments were reported to gain as much as 2 to 5lbs within one to four weeks of supplementation. Many researchers believe that some of this can be attributed to increase levels of water retention within cells caused by osmotic pressure resulting from the Creatine uptake. The belief is that the water retention causes the cell to become enlarged, and so the cell is able to synthesized more contractile protein particularly in the type II fibers (fast twitch)(4).
The phosphorylation reaction of ADP by phosphocreatine consumes hydrogen ion; thus it may reduce acid content in the muscles. Furthermore, the improved turnover rate of ATP caused by an increase level of Creatine reduces the cell?s reliance on glycolysis. Therefore, less lactate is formed(3). This has been indicated in studies that observed lower muscle lactate levels after exercise (4). An increase ratio of ATP to ADP in skeletal muscle cells (fiber) causes the cells to be more relaxed during the resting state. Therefore, they have greater contractile potential for high-powered movements(1). Such as throwing a shot put or performing a high jump. Creatine is a true athletes supplement. It allows an athlete to become bigger, faster, and stronger. Creatine almost works like magic and gives the athlete an extra boost when it is really needed, and the athlete is struggling.
The side effects of Creatine monohydrate are were minimal so far and are nausea, upset stomach, dizziness, or weakness, loose stools or diarrhea; and generally occur with dosages greater than 5 grams a day. Muscle cramping is also commonly reported, the cause of this, many scientist believe, is because the users doesn?t drink enough water while working out, and with Creatine the athlete can dehydrate much quicker because water gets absorbed into the muscles faster. Long-term consequences of daily Creatine ingestion, especially in high dosages, are currently unknown. There is a strong possibility that excess Creatine can put stress on the kidneys.
Androstenedione is a direct precusor in the biosynthesis to testosterone. It?s naturally made in both men and women. And it?s also found in the tree pollen scotch pine trees.
Andro was first isolated in 1935, but it wasn?t looked into until the late 50?s when scientists determined andro is converted in the body to testosterone. There are two different pathways in the body that can create andro: either from DHEA (dehydroepiandrosterone) or from a hormone called ?17 alpha-hydroxyprogesterone.? Scientist found andro could be converted to testosterone (and vice versa). Andro is a steroid hormone that is the precursor to testosterone the steroid hormone associated with masculinity (1,2). It is converted from cholesterol, a reaction, or chain of reactions, that occurs in order to covert molecule A into molecule B. Specific enzymes and hormones, among other things, must be present and ready to work, so to speak, for these conversions to take place. Andro has a very short half-life in the blood and is produced by the adrenal glands and the gonads from either 17-alpha-hydroxyprogestrone or dehydroepiandrosterone(DHEA)(3). DHEA is also sold as a dietary supplement. Andro may be converted into either testosterone or an estrogen (estrone) within the blood (4).
Andro itself is a relatively weak androgen(2,4). However, the anabolic effects of testosterone are well documented. One study reported that supraphysiologic doses of testosterone significantly increased muscle size and strength in normatestosterogonic men after 10 weeks.(4) Supplementation with andro, the immediate precursor to testosterone is believed to elevate blood testosterone levels in both males and females and thus increase lean body mass (muscle mass) and physical strength.
The andro supplements, which are becoming so popular among bodybuilders, are tablets and capsules. How effective are these oral supplements, well, one study, quoted in a German patent application, stated that oral doses of andro, given to men at levels of 50mg and 100mg, raise testosterone levels by 140% and 183% and 211% to 237% respectively. Another study, preferred in the U.S. at the medical college of Georgia, examined the effects of a 100mg dose of andro on women. The effects of andro in females seem to be more dramatic than in men these women experience a four to sixfold increase in total testosterone within an hour after oral ingestion.
A study conducted in 1962 reported that two female subjects who ingested 100mg of andro had dramatically elevated blood testosterone levels within 90 minutes of ingestion. At 60 minutes, serum testosterone concentration increased by approximately 400% in one of the subjects and nearly 700% in the other subject. Serum testosterone concentration remained elevated both subjects for about 90 minutes before returning to the normal level. (2)
Since andro seems to cause a brief burst of testosterone, it may or may not cause any of the unusual testosterone side effects: acne, prostate, hypertrophy, and a decrease in HDL (good) cholesterol.
Because it does fall under the category of steroid hormones, and because it was shown to have androgenic and anabolic properties, it may produce side effects similar to those of testosterone based anabolic steroids. The most dangerous of them is the increased risk you put yourself at for heart disease, contain cancers, depression, psychoses, and even extreme aggression. There are also sex specific effects. For men, these include shrinking testes, increased hair loss, enlarged breasts, and possible sterility. Woman may experience such side effects as shrinking breast and uterus, enlarged clitoris, irregular menstruation, increased facial and body hair growth, and a deepening voice.
The overall effects of andro have been shown to increase strength and quicker, more productive muscle recover, therefore the athletes will be bigger and stronger helping them perform better than they did.
HMB is otherwise known as ?beta-hydroxy beta-methylbutyrate.? It?s a metabolite of the essential amino acid leucine. Our body?s make some HMB but we also get some from food- it?s found in small amounts in both plants and animals foods, including: grapefruit and catfish. HMB is not a steroid or drug.
HMB appears to up-regulate our ability to build muscle and burn fat in response to intense exercise. In fact in one recent study recently published in the prestigious Journal of Applied Physiology, it was revealed that athletes who supplemented their diets with three grams of HMB a day, for just three weeks, gained three times as much lean body mass and experienced an increase in strength two and a half times greater than test subjects who followed the same workout program but used a placebo(5).
HMB has been shown to have a positive effect on protein metabolism. HMB also appears to be safe and non-toxic. It has also been shown to have only positive effects on health and human metabolism with HMB supplementation.
HMB seems to shift the balance of protein metabolism in favor of new muscle growth, and it also appears to minimize the breakdown of muscle tissue (an anti-catabolic effect). In doing so, HMB can help support a consistent increase in muscle tissue growth. According to studies HMB supplementation may double the muscle building and fat burning effects of exercise.
It is unknown exactly how HMB works but it may supply a precursor to muscle and to the immune system that supports maximal cellular repair. Thus, the muscle membrane is more rapidly repaired after exercise-induced damage, and having an adequate supply of this substrate in the muscle for membrane expansion supports muscle growth. The result is a more rapid return to position protein synthesis.
Another hypothesis is that HMB supports a decrease inn protein turnover or muscle damage. In turn, this decrease in muscle breakdown could result in more rapid neural recruitment by the muscle fibers and may act as a catalyst to faster strength increases. This could explain why in scientific studies, test subjects using HMB noticed a dramatic increase in strength after using the supplement for only a week or two.
HMB is a normal product of human metabolism; it is naturally present in mother?s milk and is found in small quantities in the foods we eat. HMB also appears to be an essential part of the tissue growth process. In addition, it?s a water-soluble compound, which is excreted in the urine in proportion to dietary intake. Thus, based on the chemistry of HMB, it would be predicted that HMB is a Seabee compound.
In the discussion of these three supplements you can see that they do have an overall effect on an athletes performance. It is proven that these supplements help athletes too gain strength, speed and endurance. In gaining these they are able to perform at an elevated level beyond that of what they were capable before.
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