Without supplementation, approximately 14.6mmol (2g) of creatinine, creatine’s urinary metabolite, is lost on a daily basis in a standard 70kg male ages 20-39. The value is slightly lower in females and the elderly due to a presence of less muscle mass. This amount is considered necessary to obtain in either food or supplemental form to avoid creatine deficiency. Requirements may be increased in people with higher than normal lean mass. Creatine excretion rates on a daily basis are correlated with muscle mass, and the value of 2g a day is derived from the aforementioned male population with about 120g creatine storage capacity. Specifically, the rate of daily creatine losses is about 1.6%-1.7%, and mean losses for women are approximately 80% that of men due to less average lean mass. For weight-matched elderly men (70kg, 70-79 years of age) the rate of loss of 7.8mmol/day, or about half (53%) that of younger men.
How does creatine work? For those who remember their high school biology, creatine acts as an extra reservoir for phosphate groups. When your body starts running out of readily-available ATP (for example, when lifting weights), creatine can help donate some phosphate to ADP (to give your body more ATP). In terms of real-life application, creatine basically gives your cells a bit more extra energy.
Peirano, R. I., Achterberg, V., Dusing, H. J., Akhiani, M., Koop, U., Jaspers, S., Kruger, A., Schwengler, H., Hamann, T., Wenck, H., Stab, F., Gallinat, S., and Blatt, T. Dermal penetration of creatine from a face-care formulation containing creatine, guarana and glycerol is linked to effective antiwrinkle and antisagging efficacy in male subjects. J.Cosmet.Dermatol. 2011;10(4):273-281. View abstract.
Makes You Healthier: If you’re looking for a workout in which you get the biggest bang for your buck, strength training is it. Strength training increases bone density, builds a stronger heart, reduces your resting blood pressure, improves blood flow, halts muscle loss, helps control blood sugar, improves cholesterol levels, and improves your balance and coordination (turning you from this, to this).
As scientific research progressed, it became apparent that the best types of protein came from milk and eggs. That led to the next great revolution in sports nutrition, namely the engineered food, pioneered by Scott Connelly, M.D., a critical care specialist from Northern California who teamed with a young entrepreneur named Bill Phillips from Golden, Colorado.
It is prudent to note that creatine supplementation has been shown to reduce the body’s endogenous production of creatine, however levels return to normal after a brief period of time when supplementation ceases [1,6]. Despite this creatine supplementation has not been studied/supplemented with for a relatively long period. Due to this, long term effects are unknown, therefore safety cannot be guaranteed. Whilst the long term effects of creatine supplementation remain unclear, no definitive certainty of either a negative or a positive effect upon the body has been determined for many health professionals and national agencies [19,78]. For example the French Sanitary Agency has banned the buying of creatine due to the unproven allegation that a potential effect of creatine supplementation could be that of mutagenicity and carcinogenicity from the production of heterocyclic amines . Long term and epidemiological data should continue to be produced and collected to determine the safety of creatine in all healthy individuals under all conditions .
Few supplements have the solid scientific foundation that creatine has. Studies show that it's effective for 80 percent of those who use it. Since creatine is found naturally in meat, the more meat you eat, the less likely you'll need creatine supplementation. Vegetarians or those who rarely eat meat, however, can get huge boosts from most creatine supplements.
A recent review article published in The American Journal of Clinical Nutrition highlighted the benefits of protein supplementation and showed that supplementing with protein during prolonged (greater than 6 weeks) resistance-type training can lead to significantly greater increases in muscle mass and strength when compared to resistance training without a dietary protein intervention.
Taking creatine can also cause 5-10 lbs of water-weight gain. The stress from extra water causes muscle cells to grow faster. This is one reason why creatine supplementation increases muscle growth over the long term. Novice weightlifters see more benefits with creatine than seasoned athletes, since they have more muscle to gain. (That doesn’t mean athletes shouldn’t take creatine though.)
When lifting to complete fatigue, it takes an average of two to five minutes for your muscles to rest for the next set. When using lighter weight and more repetitions, it takes between 30 seconds and a minute for your muscles to rest. For beginners, working to fatigue isn't necessary, and starting out too strong can lead to too much post-exercise soreness.
The last survivors of the pro-hormone supplements, which were removed from sale last January, estrogen-blocking supplements aren't pro-hormones but do inhibit the enzyme aromatase, which converts androgens into estrogens. In normal men that enzyme is ubiquitous, being present in such tissues as muscle, brain and skin. About 20 percent of the free testosterone circulating in the blood is converted into estrogen by way of aromatase.
Cranking up the levels of testosterone within the body, XPI's Testosyn is formulated with 100% natural and powerful ingredients to build lean muscle, boost sex drive, and increase energy levels. Using a high-performance testosterone complex that contains D-Aspartic Acid, Fenusterols, and Tribulus Terrestris, this potent supplement will aid in the enhancement of each workout and promote free testosterone. Testosyn's ingredients have the ability to increase testosterone levels nearly twice as much as other products for more strength, mass, and sexual vigor. Keep Reading »
Stand with your feet slightly wider than shoulder width with a kettlebell about a foot in front of you. With your weight in your heels, hinge at your hips while lowering your hands to the kettlebell handle. Grab the kettlebell with an overhand grip, “Hike” the kettlebell back between your legs, catching the force of the moving kettlebell with your hips. Exhale as you swing the kettlebell forward by thrusting your hips, straightening your legs, and squeezing your glutes and abs. Once the kettlebell reaches chest height, inhale as you allow it to fall, and guide it back to the “hiked” position.
In contrast to the above null effects, ingestion of creatine both before and after a workout (alongside protein and carbohydrate) over 10 weeks seems to promote muscle growth more than the same supplement taken in the morning, farther away from the time of the workout. The benefits of creatine around the workout, relative to other times, have been hypothesized to be related to an upregulation of creatine transport secondary to muscle contraction, a known phenomena.
In an article entitled Active Seniors Enjoy Life More, the American Council on Exercise reports, “As you grow older…regular exercise can help boost energy, maintain your independence, and manage symptoms of illness or pain. Exercise can even reverse some of the symptoms of aging.” Wow! Are you sold yet? But wait, there’s more. While taking your daily walk remains a crucial piece of this exercise pie, getting in your strength training reps is the part that will truly make the difference in your well-being. The Center for Disease Control and Prevention (“CDC”) recommends strength training for most older adults to help lessen the symptoms of the following chronic conditions:
Creatine is an organic acid naturally occurring in the body that supplies energy to muscle cells for short bursts of energy (as required in lifting weights) via creatine phosphate replenishment of ATP. A number of scientific studies have shown that creatine can improve strength, energy, muscle mass, and recovery times. In addition, recent studies have also shown that creatine improves brain function. and reduces mental fatigue. Unlike steroids or other performance-enhancing drugs, creatine can be found naturally in many common foods such as herring, tuna, salmon, and beef.
In a later study, it was found that biologically relevant concentrations (10-30mM) of creatine bind synthetic membranes with lipid compositions mimicking the inner mitochondrial membrane or plasma membrane in a concentration-dependent manner. This also conferred a degree of protection, increasing membrane stability in response to challenge from a number of destabilizing agents. Phosphocreatine was more effective than creatine in this context, although both were able to bind and stabilize membranes.
How to do it: In general, your feet should be shoulder-width or slightly wider apart (if you’ve got a bigger frame go wider; if you’re smaller, go closer together), and your feet planted firmly on the floor, driving and emphasizing that heel drive. Stand tall. Depending on your preference or what’s available, hold a dumbbell in each hand (arms down at your sides); position yourself under a barbell with the bar against your traps for a back squat, and just over your chest for a front squat; hold a kettbell or dumbbell at your chest for goblet squats; wrap resistance bands under your feet and around your shoulders; or, use just your bodyweight to perform a basic squat.
When endothelial cells have a higher creatine concentration, they appear to be mildly less permeable when incubated with 0.5-5mM creatine, while the higher concentration (5mM) is able to fully ablate TNF-α-induced neutrophil adhesion and both E-selectin and ICAM-1 expression. This effect was prevented with ZM241385, an A2A (adenosine) receptor antagonist, and since adenosine released by this receptor is known to be protective of endothelial cells, it is thought that creatine works vicariously through this receptor and adenosine release, thought to be due to releasing ATP (occurs in response to stress) which protects the cell via the A2A signaling system.
Multivitamin: A bodybuilder’s regime is strict and consuming the essential nutrients is an integral part of the process. The entire process can take a very nasty turn if one is not careful with the amount and type of food intake. The intake of multi vitamins can, therefore, have a good impact on a body builder. These multivitamins are used so that essential vitamins and minerals are supplied to the body, to promote good health and also allow a constant flow of energy.
However, the basis of “take creatine after your workout” comes from a 2013 study published in the JISSN, which can be found here (open access too!). In this study, recreational male bodybuilders (19 men overall) were given five grams of creatine either before or after their workouts. They trained five days per week but were also directed to consume 5g on their rest days at any time they wanted. The workouts were fairly similar to most gym workouts, and the methodology (what they did and how they did it) suggests that the findings would apply to most weightlifters.
In elite swimmers, the growth hormone response to sprints appears to be attenuated (39%) following creatine loading, although after a 3g maintenance phase (22-27 weeks), this attenuation was reduced to less than 5%. Elsewhere in swimmers, resting growth hormone was unaffected by the loading phase, suggesting that this is an exercise-exclusive effect.
In a pilot study on youth with cystic fibrosis, supplementation of creatine at 12g for a week and 6g for eleven weeks afterward was associated with a time-dependent increase in maximal isometric strength reaching 14.3%, which was maintained after 12-24 weeks of supplement cessation (18.2% higher than baseline). This study noted that more patients reported an increase in wellbeing (9 subjects, 50%) rather than a decrease (3, 17%) or nothing (6, 33%) and that there was no influence on chest or lung symptoms.
Prison food isn’t as bad as people think. Prisoners often get three meals a day. Meals need to meet a certain amount of calories. You don’t need that much protein to build muscle, but prisoners can buy protein powder (and also extra food like oatmeal). Prisoners aren’t underfed in most western countries. The diet may not be optimal, but it’s sufficient to build muscle.
Moving through repetitions too quickly, going too fast; there is nothing gained by lifting weights fast. Some of the perks of lifting weight in a slow and controlled manner, include more total muscle tension and force produced, more muscle-fiber activation both slow and fast twitch fibers, and less tissue trauma. Remember, a joint is only as strong as the muscles that cross it; if you haven't lifted in a long time, or ever, be careful what you ask of your joints.
Han:SPRD‐cy rats (human polycystic kidney disease model) have pre-existing renal damage, which is accelerated upon ingestion of creatine supplementation at 0.3% of the diet for five days and 0.03-0.05% for the next 35 days (equivalent to human loading and maintenance). During this particular disease state, renal water content and size progressively increases. Since creatine supplementation furthered the increase by an additional 2.1%, it was thought that this property of creatine explained the 23% increased cyst scores seen relative to control.
In my late 20’s, I visited an anti-aging doctor who was one of the pioneers of what we now call functional medicine. I got a full hormone test. Shockingly, my testosterone was lower than my mother’s. No wonder I felt crappy and was overweight. My other sex hormones were out of whack too, especially my estrogen levels. They were high because the little testosterone I did make my body converted into estrogen. I went on a mix of topical replacement testosterone cream, plus small doses of pharmaceuticals like clomid and arimidex in order to keep my other sex hormones functioning properly.
Our Keep-It™ guarantee is valid for the first-time purchase of a formula, and redeemable up to three months (90 days) after the purchase date. Multiple bottles, foods, apparel and gear do not fall under this guarantee, however, they may be applicable for return. Fitness equipment, personal care products, knowledge purchases, and DVDs are not eligible for return or refund. For more information and a full list of products that qualify, visit our Keep-It™ page. Further details can be found on our Refund Policy support page.
Heath has 1.8 million Instagram followers, 300,000 Twitter followers, a global fan base and a growing portfolio of muscle magazine covers. He competes in just one competition a year, Mr. Olympia, for which he won the $400,000 first prize this year. He spends the rest of the year staying in shape and flying hundreds of thousands of miles for appearances, conferences and meetings. He has five sponsors, led by Ultimate Nutrition, a supplement company. All told, he earns more than $1 million a year, his agent said.
You have to fuel your body with high-quality, real, wholesome food. Eating pizza, burgers, ice cream, and fast food just because it’s high in calories is a really bad plan. You’ll feel terrible, and while the extra calories will help muscle gains to an extent, most of them will turn to fat. It’s not worth it. Your recovery will be slower and you will be riddled with inflammation.
Escolar, D. M., Buyse, G., Henricson, E., Leshner, R., Florence, J., Mayhew, J., Tesi-Rocha, C., Gorni, K., Pasquali, L., Patel, K. M., McCarter, R., Huang, J., Mayhew, T., Bertorini, T., Carlo, J., Connolly, A. M., Clemens, P. R., Goemans, N., Iannaccone, S. T., Igarashi, M., Nevo, Y., Pestronk, A., Subramony, S. H., Vedanarayanan, V. V., and Wessel, H. CINRG randomized controlled trial of creatine and glutamine in Duchenne muscular dystrophy. Ann Neurol 2005;58(1):151-155. View abstract.
In standard dosages (5-10g creatine monohydrate) the bioavailability of creatine in humans is approximately 99%, although this value is subject to change with different conjugates (forms) of creatine and dosages. Coingestion of cyclocreatine (an analogue) can reduce uptake by about half and coincubation of taurine, choline, glycine, or beta-alanine had minimal attenuation of absorption, which is likely not practically relevant. The inhibition noted with cyclocreatine may be due to receptor saturation.
According to the two meta-analyses on the topic, creatine significantly increases power when supplemented in both sexes over a period of time up to 8 weeks, during which improvement over placebo is maintained, rather than being enhanced further. The rate at which power is derived from a resistance training regimen appears to be up to 78.5% greater with creatine relative to placebo, and in active trained men who are naive to creatine, this can be quantified at about 7kg for the bench press and 10kg for the squat over 8 weeks.
This test measures a participant's ability to stand up from a seated position as many times as possible in a thirty-second period of time. Testing the number of times a person can stand up in a thirty-second period helps assess strength, flexibility, pain, and endurance, which can help determine how far along a person is in rehabilitation, or how much work is still to be done.
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Although some men believe that taking testosterone medications may help them feel younger and more vigorous as they age, few rigorous studies have examined testosterone therapy in men who have healthy testosterone levels. And some small studies have revealed mixed results. For example, in one study healthy men who took testosterone medications increased muscle mass but didn't gain strength.
In a mouse model of allergin-induced asthma, where mice were sensitized by ovalbumin for three weeks and then given 500mg/kg creatine, supplementation induced an increase in asthmatic hyperresponsiveness to low but not high doses of methacholine. This hyperresponsiveness was associated with increased eosinophil and neutrophil infiltration into the lungs, and an increase in Th2 cell cytokines (IL-4 and IL-5) alongside an increase in IGF-1, which is known to influence this process. Interestingly, there was a nonsignificant increase in responsiveness in mice not sensitized to ovalbumin.
Men who produce more testosterone are more likely to engage in extramarital sex. Testosterone levels do not rely on physical presence of a partner; testosterone levels of men engaging in same-city and long-distance relationships are similar. Physical presence may be required for women who are in relationships for the testosterone–partner interaction, where same-city partnered women have lower testosterone levels than long-distance partnered women.
Testicular diseases which may cause low T include inherited conditions such as undescended testis, Klinefelter’s syndrome, and acquired conditions such as Mump’s orchitis, trauma to the testicles, and damage caused by cancer treatment. Conditions which may affect the regulatory functions of the hypothalamus and pituitary gland include medications such as opioid pain medications and steroids, kidney failure, tumors, tuberculosis, sarcoidosis, HIV/AIDS, obesity, and physical or emotional stress.
JAK2 (Janus-Activating Kinase 2) is a novel protein that has been shown to suppress the activity of the creatine transporter CrT in vitro. The effects of JAK2 on CrT are not well-understood in vivo, however. Given that growth hormone activates both c-src (increases CrT activity) and JAK2- which has been found to decrease CrT activity, it is plausible that JAK2 may function as a negative-feedback regulator of creatine uptake. Future research is needed to better understand the role of JAK2 on CrT activity in vivo.
Some of these medications that can harm the kidneys include cyclosporine (Neoral, Sandimmune); aminoglycosides including amikacin (Amikin), gentamicin (Garamycin, Gentak, others), and tobramycin (Nebcin, others); nonsteroidal anti-inflammatory drugs (NSAIDs) including ibuprofen (Advil, Motrin, Nuprin, others), indomethacin (Indocin), naproxen (Aleve, Anaprox, Naprelan, Naprosyn), piroxicam (Feldene); and numerous others.
Mr. Olympia is part of the International Federation of Bodybuilding Professional League. The I.F.B.B. says that it operates under the guidelines of the World Anti-Doping Agency and that competitors are subject to drug testing. Chang, who oversees the Mr. Olympia contest, said that I.F.B.B. testing is random, but is not conducted during the Mr. Olympia contest itself.
Place a band around your ankles. Shift your weight into your right foot and place the toes of your left foot on the ground about an inch behind your right foot, so there is tension in the band. Exhale as you kick your left leg back about six inches. Avoid arching your back and keep your knees straight. Inhale as you return your left foot to the starting position. Do 10-12 reps. Switch sides.
The creatine kinase (CK) enzyme in rat heart tissue appears to have a KM around 6mM of creatine as substrate. and is known to positively influence mitochondrial function as higher cytoplasmic phosphocreatine concentrations (not so much creatine per se) increase the oxidative efficiency of mitochondria This is thought to be due to the transfer of high energy phosphate groups.
Although research is underway, doctors do not know the long-term health effects of taking creatine supplements, especially in children who are still growing. Because of these unknown risks, children and adolescents younger than 18 years and pregnant or nursing women should never take creatine supplements. People with kidney problems also should never take creatine supplements.
Homocyteine (normal serum range of 5-14µM) is known to adversely affect motor control in genetically susceptible people when their levels exceed 500µM, which is usually associated with genetically induced deficiencies of B12. In these particular instances (assessed by rats fed homocysteine to increase serum levels to such a high level) it appears that administration of 50mg/kg creatine (injections) to these rats can protect dysfunction in muscle metabolism (pyruvate kinase activity, Krebs cycle intermediates, and muscle cell viability) induced by homocysteine.
Researchers described the study as one of the first to examine how strength training can reduce the risk of cardiovascular disease, separate from the effects of aerobic activity like running or long walks. The point: for those who are not meeting recommended guidelines for aerobic activity—perhaps because they lack the time—bursts of weight training can be enough.
It’s an amazing feeling when you graduate from lifting 10-pounders to 15-pounders. “Over time, you get better at something you’re doing, and you develop a sense of mastery and feeling that you’re getting stronger,” explains James Whitworth, a doctoral research fellow in the Biobehavioral Resistance Training Lab at Columbia’s Teachers College in New York City. “It helps your confidence, and that gives you a boost in self-esteem.”
In young rats given creatine in the diet at 2% of the diet for eight weeks, supplementation appears to increase bone mineral density (BMD) in the lumbar spine with a nonsignificant trend to increase BMD in the femur. Despite the trend, the femur appeared to be 12.3% more resistant to snapping from mechanical stress associated with increased thickness. Menopausal rats (ovarectomized) experience similar benefits, as supplementation of creatine (300mg/kg) for eight weeks during ovarectomy is able to increase phosphorus content of the bone and other biomarkers of bone health, although bone stress resistance was not tested.
The maximum amount of creatine the body can store is about 0.3 gram per kilogram of body weight . The creatine content of skeletal (voluntary) muscles averages 125 millimoles per kilogram of dry matter (mmol/kg/dm) and ranges from about 60 to 160 mmol/kg/dm. Approximately 60% of muscle creatine is in the form of PCr. Human muscle seems to have an upper limit of creatine storage of 150 to 160 mmol/kg/dm. Athletes with high creatine stores don't appear to benefit from supplementation, whereas individuals with the lowest levels, such as vegetarians, have the most pronounced increases following supplementation. Without supplementation, the body can replenish muscle creatine at the rate of about 2 g/day .
Walnuts are a dietary paradox – or at least they appear that way. As you probably know, walnuts are very calorically dense, mainly because of their fat content. Just one ounce of walnuts – that is about 12-14 halves – contains 185 calories. If you’ve ever tracked your food intake, you know that sort of thing can add up very quickly, especially if you’re just grabbing handfuls and not measuring.
The participants were seen every 4 weeks. Blood was taken to measure hormone levels, and questionnaires were given to assess physical function, health status, vitality, and sexual function. Body fat and muscle measurements were also taken at the beginning and end of the 16 weeks. The study was funded in part by NIH’s National Institute on Aging (NIA) and National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Results appeared in the September 12, 2013, issue of the New England Journal of Medicine.
Cornelissen, V. A., Defoor, J. G., Stevens, A., Schepers, D., Hespel, P., Decramer, M., Mortelmans, L., Dobbels, F., Vanhaecke, J., Fagard, R. H., and Vanhees, L. Effect of creatine supplementation as a potential adjuvant therapy to exercise training in cardiac patients: a randomized controlled trial. Clin.Rehabil. 2010;24(11):988-999. View abstract.
Creatine, which is synthesized in the liver and kidneys, is transported through the blood and taken up by tissues with high energy demands, such as the brain and skeletal muscle, through an active transport system. The concentration of ATP in skeletal muscle is usually 2–5 mM, which would result in a muscle contraction of only a few seconds. During times of increased energy demands, the phosphagen (or ATP/PCr) system rapidly resynthesizes ATP from ADP with the use of phosphocreatine (PCr) through a reversible reaction with the enzyme creatine kinase (CK). In skeletal muscle, PCr concentrations may reach 20–35 mM or more. Additionally, in most muscles, the ATP regeneration capacity of CK is very high and is therefore not a limiting factor. Although the cellular concentrations of ATP are small, changes are difficult to detect because ATP is continuously and efficiently replenished from the large pools of PCr and CK. Creatine has the ability to increase muscle stores of PCr, potentially increasing the muscle’s ability to resynthesize ATP from ADP to meet increased energy demands.
Testosterone is the primary male sex hormone and an anabolic steroid. In male humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. In addition, testosterone is involved in health and well-being, and the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty and bone loss.
In vitro studies on endothelial cells have noted that the benefits of creatine against atherosclerosis (via immune cell adhesion to the endothelial cell) are blocked with the pharmaceutical ZM241385, a high affintiy adenosine A2A receptor antagonist. This particular receptor subset (A2A rather than other adenosine receptors) and its inhibition are similar to caffeine, suggesting that caffeine may have an inhibitory effect on this mechanism of creatine.
Bodybuilders spend years and years of their lives focused on perfecting the human body through proper training and nutrition. You, on the other hand, might not have an interest in the sport of bodybuilding, but do want to know the secrets to six-pack abs, a wide back, and rounded shoulders. And what better place to score the tricks of the trade than from 3-time Mr. Olympia Phil Heath.
It arises from the posterior gluteal line of the inner upper ilium, a pelvic bone, and roughly the portion of the bone including the crest of the ilium (the hip bone), immediately above and behind it; and from the posterior surface of the lower part of the sacrum, the base of the spine, and the side of the coccyx, the tailbone; from the aponeurosis of the erector spinae (lumbodorsal fascia), the sacrotuberous ligament, and the fascia covering the gluteus medius (gluteal aponeurosis). The fibers are directed obliquely downward and lateralward; The gluteus maximus has two insertions:
A 2011 survey of 33 supplements commercially available in Italy found that over 50% of them exceeded the European Food Safety Authority recommendations in at least one contaminant. The most prevalent of these contaminants was creatinine, a breakdown product of creatine also produced by the body. Creatinine was present in higher concentrations than the European Food Safety Authority recommendations in 44% of the samples. About 15% of the samples had detectable levels of dihydro-1,3,5-triazine or a high dicyandiamide concentration. Heavy metals contamination was not found to be a concern, with only minor levels of mercury being detectable. Two studies reviewed in 2007 found no impurities.
^ Jump up to: a b Travison TG, Vesper HW, Orwoll E, Wu F, Kaufman JM, Wang Y, Lapauw B, Fiers T, Matsumoto AM, Bhasin S (April 2017). "Harmonized Reference Ranges for Circulating Testosterone Levels in Men of Four Cohort Studies in the United States and Europe". The Journal of Clinical Endocrinology and Metabolism. 102 (4): 1161–1173. doi:10.1210/jc.2016-2935. PMC 5460736. PMID 28324103.
^ Butenandt A, Hanisch G (1935). "Umwandlung des Dehydroandrosterons in Androstendiol und Testosterone; ein Weg zur Darstellung des Testosterons aus Cholestrin" [About Testosterone. Conversion of Dehydro-androsterons into androstendiol and testosterone; a way for the structure assignment of testosterone from cholesterol]. Hoppe-Seyler's Z Physiol Chem (in German). 237 (2): 89–97. doi:10.1515/bchm2.1935.237.1-3.89.
A meta-analysis of 16 studies conducted on creatine and its influence on power and strength, (with or without exercise in all age groups above 16, but placebo controlled and without crossover) compiled studies utilizing a 5-7 day loading period with continued maintenance thereafter and studies assessing 1-3 rep bench press strength in trained young men. Seven studies (four of which are online) totaling 70 people using creatine and 73 people in placebo showed a 6.85kg increase in strength relative to placebo, the benefits of which peaked at 8 weeks. This meta-analysis also quantified a significant increase in squat strength (9.76kg) yet failed to find a significant influence on peak bicep contraction power, which may have been influenced by the two null studies being in elderly people while the positive study was statistically outweighed, but noted an 1.8-fold increase in power associated with creatine over placebo. The other meta-analysis conducted the following year calculated effect sizes for creatine supplementation and noted no significant differences between genders or when comparing trained and untrained individuals. The mean effect size of exercises lasting below 30s (those that use the creatine-phosphate system) was 0.24+/-0.02 and performed significantly better than placebo, where exercise increased performance by 4.2+/-0.6% while the addition of creatine enhanced this effect to 7.5+/-0.7%.
Whenever you hear the word, “bodybuilding”, your mind usually flashes you images of bulging muscles, steel, sweat, the shouts of weightlifters, and ripped, muscular bodies of men and women in skimpy spandex. Your mind instantly takes you to the gym followed by wishful thinking that you can have a sexy body and bigger muscles. However, it takes more than just