The Branched-Chain Amino Acids, BCAAs for short, are leucine, valine and isoleucine.  Essentially, its a form of protein powder for muscle gain or other uses. These essential amino acids are not made by the body but are found in foods such as meats, dairy products and legumes. In medicine, BCAAs are used for a number of conditions, however, for many uses, further research is necessary to determine whether or not treatment is effective.
In females, this test can find the reason you’re missing periods, not having periods, or having a hard time getting pregnant. Doctors can also use it to diagnose polycystic ovary syndrome (PCOS). That’s a hormone problem that can cause irregular periods and make it hard to get pregnant. A testosterone test can also reveal if you might have a tumor in your ovaries that affects how much of the hormone your body produces.
In non-human primates, it may be that testosterone in puberty stimulates sexual arousal, which allows the primate to increasingly seek out sexual experiences with females and thus creates a sexual preference for females.[39] Some research has also indicated that if testosterone is eliminated in an adult male human or other adult male primate's system, its sexual motivation decreases, but there is no corresponding decrease in ability to engage in sexual activity (mounting, ejaculating, etc.).[39]
Injections of creatine are known to be neuroprotective against low oxygen levels (hypoxia) even to neonatal rats.[532] This is thought to be associated with the increased collective pool of phosphocreatine and creatine.[236] Since oral ingestion of creatine by the mother increases brain concentrations of creatine by 3.6% in the fetus prior to birth,[531] it is thought to be protective in the fetuses subject to hypoxic (low oxygen) stressors, such as a caesarean section.
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Although creatine is a natural component of food, the amount of food required to supersaturate the muscle with PCr may not be feasible. For example, it could require 22 pounds of meat daily [8]. If creatine monohydrate is proven to be a safe and effective ergogenic aid, creatine supplementation may be the simplest way to increasing muscle stores. It may be beneficial to avoid caffeine if taking creatine supplements. One study showed that caffeine diminished strength gains seen with creatine use [9].
McArdle’s disease is a myopathy associated with impaired glucose release from glycogen and impairments in muscle function at times when glucose would be the primary energy substrate. Creatine is thought to be therapeutic, but has shown differing effects in the two trials so far (both benefit and worsening of symptoms) for currently unknown reasons.
Low testosterone levels can cause mood disturbances, increased body fat, loss of muscle tone, inadequate erections and poor sexual performance, osteoporosis, difficulty with concentration, memory loss and sleep difficulties. Current research suggests that this effect occurs in only a minority (about 2%) of ageing men. However, there is a lot of research currently in progress to find out more about the effects of testosterone in older men and also whether the use of testosterone replacement therapy would have any benefits.
Guanidoacetate (made by AGAT) then receives a methyl donation from S-adenosyl methionine via the enzyme guanidinoacetate methyltransferase (GAMT), which produces S-adenosylhomocysteine (as a byproduct) and creatine. Deficiencies in GAMT are more severe (although equally rare) relative to AGAT, resulting in severe mental retardation and autism-like symptoms.[31]
Maughan RJ, King DS, Lea T. Dietary supplements. J Sports Sci. 2004 Jan;22(1):95-113.Kreider RB. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Med. 1999 Feb;27(2):97-110.Kerksick CM, Rasmussen CJ, Lancaster SL, et al. The effects of protein and amino acid supplementation on performance and training adaptations during ten weeks of resistance training. J Strength Cond Res. 2006 Aug;20(3):643-53.Update of Cochrane Database Syst Rev. 2001;(1):CD002946. Glucosamine therapy for treating osteoarthritis. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD002946.AIS Sports Nutrition - AIS Sports Supplement Program 2007.
Crave instant gratification? Strength training is a good motivator because you see progress quickly. “If you put someone on a walking program, it will take time before they perceive their body is changing,” explains Katula. “But with strength training, you can feel a difference in your muscles even after one session.” And it only takes a couple workouts before you’ll notice some muscle definition in the mirror. (Go ahead and flex. We dare you.)
The maximum amount of creatine the body can store is about 0.3 gram per kilogram of body weight [6]. 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 [7].
"Your glutes are made up of three different muscles, the gluteus maximus, medius, and minimus," says Lefkowith. "They externally rotate your hip, abduct your hip, extend your hip, and even posteriorly tilt your pelvis." Because of this, it is important that you not only work one or two of these muscles, but rather, focus on showing all of them some love. "If you were only to do moves in one plane of motion, say a front lunge or squat, you wouldn't work your glutes to strengthen all of the joint actions they can perform."
You’d have to look hard to find a fitness expert who doesn’t recommend taking supplemental protein powder for building muscle. It’s one of the best supplements for building muscle on the market! In addition to serving as a muscle building supplement, protein powder can be the perfect complement to a successful weight loss plan. Studies show that the supplement can prevent loss of muscle mass, helping you lose fat exclusively instead.
Arginine mainly benefits the body in two ways. The first of these is by producing nitric oxide. When arginine enters the body, some of it gets converted into nitric oxide. Nitric oxide is important for regulating blood pressure, as it can enlarge the blood vessels. Larger blood vessels allow the body to increase blood flow throughout the body, bringing extra nutrients and oxygen to the muscles during exercise.
The benefits of weight training overall are comparable to most other types of strength training: increased muscle, tendon and ligament strength, bone density, flexibility, tone, metabolic rate, and postural support. This type of training will also help prevent injury for athletes. There are benefits and limitations to weight training as compared to other types of strength training. Contrary to popular belief, weight training can be beneficial for both men and women.
Weight training aims to build muscle by prompting two different types of hypertrophy: sarcoplasmic and myofibrillar. Sarcoplasmic hypertrophy leads to larger muscles and so is favored by bodybuilders more than myofibrillar hypertrophy, which builds athletic strength. Sarcoplasmic hypertrophy is triggered by increasing repetitions, whereas myofibrillar hypertrophy is triggered by lifting heavier weight.[23] In either case, there is an increase in both size and strength of the muscles (compared to what happens if that same individual does not lift weights at all), however, the emphasis is different.

Parashos, S. A., Swearingen, C. J., Biglan, K. M., Bodis-Wollner, I., Liang, G. S., Ross, G. W., Tilley, B. C., and Shulman, L. M. Determinants of the timing of symptomatic treatment in early Parkinson disease: The National Institutes of Health Exploratory Trials in Parkinson Disease (NET-PD) Experience. Arch Neurol. 2009;66:1099-1104. View abstract.


Bodybuilding became more popular in the 1950s and 1960s with the emergence of strength and gymnastics champions, and the simultaneous popularization of bodybuilding magazines, training principles, nutrition for bulking up and cutting down, the use of protein and other food supplements, and the opportunity to enter physique contests. The number of bodybuilding organizations grew, and most notably the International Federation of Bodybuilders (IFBB) was founded in 1946 by Canadian brothers Joe and Ben Weider. Other bodybuilding organizations included the Amateur Athletic Union (AAU), National Amateur Bodybuilding Association (NABBA), and the World Bodybuilding Guild (WBBG). Consequently, the male-dominated contests grew both in number and in size. Besides the many "Mr. XXX" (insert town, city, state, or region) championships, the most prestigious titles[according to whom?] were Mr. America, Mr. World, Mr. Universe, Mr. Galaxy, and ultimately Mr. Olympia, which was started in 1965 by the IFBB and is now considered the most important bodybuilding competition in the world.
What happened was that, statistically speaking (less than 5% chance what was observed was due to chance means ‘significant’ for this study) there was no significant difference between pre- and post- workout, meaning that both were equally effective. This protocol did note that both groups found benefits with creatine supplementation, but they both found the same amount of benefit.
The synthesis of creatine (from guanidinoacetate via GAMT) also requires SAMe as a cofactor and is implicated in homocysteine production. While supplementation of guanidinoacetate at 0.36% (prior to SAMe) can increase homocysteine by up to 50% in rats, supplementation of creatine (0.4%) is able to suppress homocysteine by up to 25%, secondary to reducing creatine synthesis,[309] and has been replicated elsewhere with 2% of the rat diet, while a loading phase did not alter the benefits.[124]

de Salles Painelli V, Alves VT, Ugrinowitsch C, et al. Creatine supplementation prevents acute strength loss induced by concurrent exercise. Eur J Appl Physiol 2014;114:1749-55.del Favero S, Roschel H, Artioli G, et al. Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids 2012;42:2299-305. View abstract.
A retrospective study [81], that examined the effects of long lasting (0.8 to 4 years) CM supplementation on health markers and prescribed training benefits, suggested that there is no negative health effects (including muscle cramp or injuries) caused by long term CM consumption. In addition, despite many anecdotal claims, it appears that creatine supplementation would have positive influences on muscle cramps and dehydration [82]. Creatine was found to increase total body water possibly by decreasing the risk of dehydration, reducing sweat rate, lowering core body temperature and exercising heart rate. Furthermore, creatine supplementation does not increase symptoms nor negatively affect hydration or thermoregulation status of athletes exercising in the heat [83,84]. Additionally, CM ingestion has been shown to reduce the rate of perceived exertion when training in the heat [85].
Weight trainers commonly spend 5 to 20 minutes warming up their muscles before starting a workout. It is common to stretch the entire body to increase overall flexibility; however, many people stretch just the area being worked that day. The main reason for warming up is injury prevention. Warming up increases blood flow and flexibility, which lessens the chance of a muscle pull or joint pain.
It's OK to be a little sore. Your muscles might feel achy or tired the day after a tough training session thanks to DOMS, or delayed onset muscle soreness. When you strength train you're causing microscopic damage to the tissue that will be repaired, that's how you build stronger lean muscle. Speaking of repair and recovery, though, rest days are important. "If you constantly break down muscle without a recovery period, you won’t give the muscle fibers a chance to repair and build back stronger,” explains Davis.

Studies measuring extracellular water versus intracellular water note similar increases in both, associated with creatine. Creatine does not tend to disturb the ratios of water to dry mass in various tissues measured.[609] At least one study in older men (48-72 years) has failed to find a significant difference in both intracellular and extracellular water concentration after 14 weeks of 5g creatine daily (with gatorade) relative to gatorade in isolation, with the ratio being maintained.[615]


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Creatine is most commonly found in the basic form of creatine monohydrate, which is the standard form and usually recommended due to the low price. It can also be micronized to improve water solubility, or the monohydrate can be temporarily removed to concentrate creatine in a small volume supplement. Neither alteration changes the properties of creatine.
“Imagine you've fasted for over eight hours,” he says. “At breakfast, you're firing your metabolism off really high. If you don't eat for another five hours, your metabolism starts to slow right down and you have to try and kickstart it again with your next meal. If you eat every two and a half to three hours, it's like chucking a log on a burning fire.”
There are positive correlations between positive orgasm experience in women and testosterone levels where relaxation was a key perception of the experience. There is no correlation between testosterone and men's perceptions of their orgasm experience, and also no correlation between higher testosterone levels and greater sexual assertiveness in either sex.[34]
After all, you’ve probably seen the countless workouts, diets, supplements, programs, products and people claiming that super fast muscle growth is possible. You’ve probably also seen the click-bait headlines (“How To Build 20lbs Of Muscle In Just 6 Weeks!”) and the unbelievable transformations of supposedly “natural” people (bodybuilders, celebrities, athletes, fitness gurus on social media, etc.) that clearly prove it can happen faster than this.
One study lasting 16 months using 10g creatine daily alongside the pharmaceutical riluzole noted that, after 34 of the patients died from ALS, creatine failed to exert protective effects against ALS-related mortality (adjusted hazard ratio of 0.78 with a 95% CI of 0.47–1.48[505]). A smaller study measuring only eight deaths noted that the six in placebo (relative to two in creatine) was too small of a sample size to detect a statistically significant difference.[506] A nonsignificant trend to increase survival has been noted elsewhere with 5g of creatine daily with a similar ratio: 3 deaths in placebo to 1 death in creatine.[507]
Minor liver lesions (grade I, no grade II or III, pathology not indicative of toxicity) have been studied in SOD1 G93A transgenic mice (a research model for amyotrophic lateral sclerosis or ALS, but used in this study to assess a state of chronic pro-oxidative stress) for 159 days with 2% of feed intake and in CD-1 rats (seen as normal) over 56 days with 0.025-0.5mg/kg in CD-1 mice, although in Sprague-Dawley rats (normal controls) there were no significant differences noted even after 2% of feed intake for 365 days.[503] These observations appear to be due to the strain of the rodents used,[504][503] and human studies on amyotrophic lateral sclerosis (ALS; what the SOD1 G93A transgenic mice are thought to represent) lasting from nine to sixteen months with subjects supplementing with up to 10g of creatine daily have failed to find any abnormalities in serum biomarkers of liver or kidney health.[505][506][507]
There is a great amount of research published on creatine supplementation; protocols of administration, forms of creatine, as well as potential side effects. Despite this, the mechanisms by which creatine acts in the human body to improve physical and cognitive performance are still not clear. The main objectives of this review are to analyze the more recent findings on the effects and mechanisms of creatine supplementation in sports and health. As a secondary purpose, we will analyze the most recommended protocols of ingestion and its potential side effects.
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Testosterone is a steroid from the androstane class containing a keto and hydroxyl groups at the three and seventeen positions respectively. It is biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites.[5] It exerts its action through binding to and activation of the androgen receptor.[5] In humans and most other vertebrates, testosterone is secreted primarily by the testicles of males and, to a lesser extent, the ovaries of females. On average, in adult males, levels of testosterone are about 7 to 8 times as great as in adult females.[6] As the metabolism of testosterone in males is greater, the daily production is about 20 times greater in men.[7][8] Females are also more sensitive to the hormone.[9]
While creatine's influence on physical performance has been well documented since the early twentieth century, it came into public view following the 1992 Olympics in Barcelona. An August 7, 1992 article in The Times reported that Linford Christie, the gold medal winner at 100 meters, had used creatine before the Olympics. An article in Bodybuilding Monthly named Sally Gunnell, who was the gold medalist in the 400-meter hurdles, as another creatine user. In addition, The Times also noted that 100 meter hurdler Colin Jackson began taking creatine before the Olympics.[12][13]
Branched-chain amino acids (leucine, isoleucine, valine) play important roles in muscle building. Some researchers have found that following exercise, the branched-chain amino acids, especially leucine, increase the rate of protein synthesis and decrease the rate of protein catabolism (Blomstrand, 2006). The billion dollar supplement industry has been quick to respond; leucine supplements are widely available in health food stores, with a cost upwards of $50 per container. However, because the research findings are inconsistent and little is known about the safety of these products, the American Dietetic Association (soon to be renamed the Academy of Nutrition and Dietetics) advises against individual amino acid supplementation and protein supplementation overall (Rodriquez, 2009). It may be that food sources of these proteins and amino acids provide the same effect for a small fraction of the cost.
You can't scroll through Instagram without clocking a mammoth cheat day feast, but are real-life bodybuilders consuming such a crazy amount of calories every couple of weeks? Not quite. When he’s dieting for a competition, Terry incorporates ‘re-feed days’ into his schedule. This means he eats the exact same food, but essentially doubles the portion sizes.
Even if your focus is on a particular body part, say getting flat abs or losing fat around the hips, it's important to work all your muscle groups. Spot reduction doesn't work, so doing crunches for your abs or leg lifts for your thighs isn't going to help you achieve your goal. What does work is building more lean muscle tissue and burning more calories.

To do dips, place your hands at shoulder-width apart on a bench, with your body and feet stretched out in front of the bench. Slowly bend your elbows and lower your body down so that your butt nearly touches the floor. Lift back up with your arms to starting position; repeat, doing 3 x 8. If this isn't a high-intensity set for you, increase the resistance by lifting one foot off the floor.
Increasing creatine levels in skeletal muscle to 687% of baseline (0.5mM creatine, thought to be equivalent to 5g creatine[135]) doesn’t seem to per se increase glucose uptake, but increases glucose oxidation (140% of baseline)[341] which is due to a two-fold increase in the activity of α1 and α2 subunits of AMPK, a potency comparable to 1mM of the reference drug AICAR.[341] Glucose uptake associated with AMPK has indeed been noted in diabetic people who are undergoing physical exercise[342] and in contracting skeletal muscle cells,[153][330] but according to rat[343][344][345] and in vitro studies of cells not being contracted,[341] this is not a per se effect of non-exercising tissue but an augmentation of exercise-induced glucose uptake.

It doesn’t get more natural than getting a good night’s sleep. Research published in the Journal of the American Medical Association showed that lack of sleep can greatly reduce a healthy young man’s testosterone levels. That effect is clear after only one week of reduced sleep. Testosterone levels were particularly low between 2 and 10 p.m. on sleep-restricted days. Study participants also reported a decreased sense of wellbeing as their blood testosterone levels dropped.
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