The partial synthesis in the 1930s of abundant, potent testosterone esters permitted the characterization of the hormone's effects, so that Kochakian and Murlin (1936) were able to show that testosterone raised nitrogen retention (a mechanism central to anabolism) in the dog, after which Allan Kenyon's group[191] was able to demonstrate both anabolic and androgenic effects of testosterone propionate in eunuchoidal men, boys, and women. The period of the early 1930s to the 1950s has been called "The Golden Age of Steroid Chemistry",[192] and work during this period progressed quickly. Research in this golden age proved that this newly synthesized compound—testosterone—or rather family of compounds (for many derivatives were developed from 1940 to 1960), was a potent multiplier of muscle, strength, and well-being.[193]
Testosterone fluctuates according to age and life circumstance, often plummeting at the onset of parenthood, and spiking (for some) during moments of triumph. Romantic relationships, too, can impact a person’s testosterone production; though the reasons are still not fully understood, entering a relationship tends to increase women’s testosterone levels, while decreasing men’s. Since males produce significantly more testosterone than females—about 20 times more each day—females can be more sensitive to these fluctuations. High levels of testosterone, particularly in men, have been correlated with a greater likelihood of getting divorced or engaging in extramarital affairs, though a causal link has not been established.
While training intensity can be accomplished trough a targeted training program and an ability to adequately stimulate our muscles is something the motivated and determined bodybuilder often has no problem doing, muscle recovery is another issue. It is especially important at a time of the year when social demands and incorrect eating combine to stifle our progress.
^ Jump up to: a b c d Brosnan JT, da Silva RP, Brosnan ME (May 2011). "The metabolic burden of creatine synthesis". Amino Acids. 40 (5): 1325–31. doi:10.1007/s00726-011-0853-y. PMID 21387089. Creatinine loss averages approximately 2 g (14.6 mmol) for 70 kg males in the 20- to 39-year age group. ... Table 1 Comparison of rates of creatine synthesis in young adults with dietary intakes of the three precursor amino acids and with the whole body transmethylation flux

A: First, you have to realize that when one is gaining weight it’s nearly impossible (steroid discussion aside) to gain solely muscle without the acquisition of some body fat as well. That being said though, you can improve thedistribution of lean body mass to fat mass by ensuring that your calorie consumption isn’t too aggressive (i.e. 1000+ over your BMR). Also, it should go without saying, but you need to be training hard while focusing on progressive overload to ensure that the calories you’re ingesting are actually going towards muscle growth. You shouldn’t be neglecting cardiovascular work either; both HIIT and LISS each play a role in enhancing mitochondrial density, balancing neurotransmitters, improving oxidative capacity, and influencing brain plasticity.

Remember that each person is unique, and each body responds differently to treatment. TT may help erectile function, low sex drive, bone marrow density, anemia, lean body mass, and/or symptoms of depression. However, there is no strong evidence that TT will help memory recall, measures of diabetes, energy, tiredness, lipid profiles, or quality of life.
“Compared to training for strength, intensity is going to drop during the hypertrophy phase of a program, with intensity sitting between 50 and 75 percent of the person’s 1RM, the maximum weight he or she can lift for one rep,” says Ava Fitzgerald, C.S.C.S., C.P.T., a sports performance coach with the Professional Athletic Performance Center in New York.
Another double-blind study supplemented with 18.75 g/day of creatine monohydrate for 5 days prior to high-intensity intermittent work to exhaustion, and then 2.25 g/day during testing. The workouts consisted of cycling to exhaustion using several protocols: (a) nonstop, (b) 60 seconds work/120 seconds rest, (c) 20 seconds work/40 seconds rest, and (d) 10 seconds work/20 seconds rest. Creatine supplementation significantly increased the total work time for all four protocols [13].
Most folks work a 9 to 5 position but if you’re not in the corporate world yet then odds are you’re a student with classes scattered throughout the day and it takes up the vast portion of your free time. That being said, you’re likely going to have to work out in the morning or the evening in order to fit in your session amidst the hectic commitments in your everyday life. Here are a few things to consider in regards to each time period:
In well-trained endurance runners, creatine (with glycerol for hyperhydration) caused a relatively large increase in body weight gain (0.90+/-0.40kg) and water weight (0.71+/-0.42L) but failed to negatively influence performance over 30 minutes in the heat.[3] This failure to improve physical performance in the heat with creatine loading (despite water retention) has been noted elsewhere.[346]

I know this goes against the recommendations you often see in stereotypical bodybuilding routines (i.e. the ones that involve having a single “chest day” or “arm day” or “shoulder day” once a week), but that’s just one of the many reasons why those types of routines suck for us natural, genetically-average people, and work best for steroid users with great genetics.
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.
Creatine may preserve dopamine synthesis in the striatum of mice (while protecting against dopaminergic depletion) when fed to mice at 2% of the diet for one week prior to MPTP toxicity[230]. This is possibly secondary to increasing tyrosine hydroxylase activity, the rate-limiting step of dopamine biosynthesis.[210][235] Two percent creatine was as protective as 0.005% rofecoxib (a COX2 inhibitor), but the two were additive in their protective effects (highly synergistic in regard to DOPAC by normalizing it, but not synergistic in preserving HVA).[230]

Why less volume for the smaller muscle groups, you ask? Partially because they are smaller, but mostly because they get a ton of indirect volume while training the bigger muscle groups (e.g. your biceps get hit pretty hard while training back, triceps get hit pretty hard while training chest and shoulders, shoulders get hit pretty hard while training chest, etc.).

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.
Adequate hydration is essential to muscle building, yet few people get enough water, even without daily exercise. So in addition to the daily 8 to 10 glasses of water recommended by the Dietary Guidelines for Americans, Karas suggests an additional 12 to 16 ounces before working out. He then recommends another 8 to 10 ounces for every 15 minutes of vigorous exercise.
With a resistance band looped around your lower thighs, lay on your right side with your arm extended along the mat and your head relaxed on your arm. Bend both knees and draw them forward slightly to bring your feet in line with your glutes, ensuring that your hips are stacked and that you maintain a small gap between your waist and the floor. This is your starting position.

Gain mass: One of the most popular reasons for people to take body building supplements is to gain weight and that is why protein powder is much sought after. Protein is the building block of muscles and therefore, bodybuilders use protein powder to help repair muscles, speed recoveries and preserve muscle mass. They usually consume 1 to 2 grams of protein per pound of body weight every day. 
Perform bent over rows to work your back. Stand with your feet shoulder-width apart, about 6 to 10 inches (15–25 cm) behind the barbell or two dumbbells. Bend slightly at the knees but keep your shins vertical. Bend forward at the waist with your spine and head straight. Lift the weight with an overhand grip up to your lower chest or upper abdomen. Lower slowly until your arms are nearly extended, without touching the ground. 3 x 8.[5]
The brain is also affected by this sexual differentiation;[13] the enzyme aromatase converts testosterone into estradiol that is responsible for masculinization of the brain in male mice. In humans, masculinization of the fetal brain appears, by observation of gender preference in patients with congenital diseases of androgen formation or androgen receptor function, to be associated with functional androgen receptors.[99]
The 100% Grass-Fed Whey Protein Isolate comes in the form of powder and can be mixed with any liquid. While the protein powder can be mixed well with water, try mixing it with milk for added calories and protein. You can even add this to smoothies and baked goods to increase the protein profile. Recommended protein intake for adults is 0.8 grams per kilogram. Some athletes may need as much as 1.2-2 grams protein per kilogram. For your specific needs, always consult a registered dietitian.
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]

A typical creatine supplementation protocol of either a loading phase of 20 to 25 g CM/d or 0.3 g CM/kg/d split into 4 to 5 daily intakes of 5 g each have been recommended to quickly saturate creatine stores in the skeletal muscle. However a more moderate protocol where several smaller doses of creatine are ingested along the day (20 intakes of 1 g every 30 min) could be a better approach to get a maximal saturation of the intramuscular creatine store. In order to keep the maximal saturation of body creatine, the loading phase must be followed by a maintenance period of 3-5 g CM/d or 0.03 g CM/kg/d. These strategies appear to be the most efficient way of saturating the muscles and benefitting from CM supplementation. However more recent research has shown CM supplementation at doses of 0.1 g/kg body weight combined with resistance training improves training adaptations at a cellular and sub-cellular level. Creatine retention by the body from supplementation appears to be promoted by about 25% from the simultaneous ingestion of carbohydrate and/or protein mediated through an increase in insulin secretion. This combination would produce a faster saturation rate but has not been shown to have a greater effect on performance.
Expert tip: To make it harder, inch yourself close to a wall so your trunk is about a foot away. Bring what would be your “planted” leg on the wall, foot flat against the surface. From here, raise your “non-working leg” up into the air, keeping your knee bent. As you raise up into the glute bridge, you’ll drive your heel against the wall, raising your hips. You can also use a bench. And like the standard bridge, you can up the ante by adding weight. 
The first published results (not blinded) noted that a loading phase of 20g of creatine for a week, followed by 3g daily for up to six months, was able to enhance maximal voluntary isometric muscular contraction (MVIC) on a dynamometer for both the knee and elbow joints, with enhanced fatigue resistance on the same joints in more than half of subjects (53-70% response rate).[545]
Testosterone was first used as a clinical drug as early as 1937, but with little understanding of its mechanisms. The hormone is now widely prescribed to men whose bodies naturally produce low levels. But the levels at which testosterone deficiency become medically relevant still aren’t well understood. Normal testosterone production varies widely in men, so it’s difficult to know what levels have medical significance. The hormone’s mechanisms of action are also unclear.
^ Jump up to: a b c Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM (2017). "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults". Br J Sports Med. 52 (6): bjsports–2017–097608. doi:10.1136/bjsports-2017-097608. PMC 5867436. PMID 28698222.
Diet – To boost your body’s testosterone levels, you need to reduce your intake of foods that promote an increase in your belly fat. Increase in belly fat promotes the activity of an enzyme called aromatase which converts testosterone to the female sex hormone, estrogen. Therefore, the greater the amount of belly fat you have, the more your level of testosterone reduces. In addition, increase your intake of heart-healthy foods such as fiber from whole grains, lean white meat, fresh fruits, and vegetables and reduce your intake of red meat and animal fat.
In the following article I will outline the supplements that have helped me to add a massive 10 kilograms (22lbs) of solid muscle to my physique over the past year—taking my body weight from 80 kilograms (176lbs) to 90 kilograms (198lbs)—and explain how these have helped me to improve my performance and enhance my size as a natural bodybuilder, aged 35.

There are many potential reasons, but I am going to keep it simple and give you just two. The first and most common reason people suffer from underactive glutes or “glute amnesia” is due to lifestyle. Even when people train hard every day, if they spend the majority of the remainder of the day sitting down, then they are simply not using their glutes. And remember the old saying - if you don’t use it, you lose it. Unfortunately, this is just what happens with your glutes.

Trimethylglycine (TMG, betaine) is a dietary supplement and component of beet root, which is a methyl donor. It contributes to metabolic processes in the body which require a methyl group either directly (the methylation of homocysteine) or indirectly via replenishing the active form of folate or via replenishing S-adenosyl methionine (SAMe). As the synthesis of creatine (via GAMT) requires a donation from SAMe,[597] it is thought that TMG can aid in creatine synthesis, which has been noted in the rat liver in the absence of creatine supplementation.[598]
A team led by Dr. Joel Finkelstein at Massachusetts General Hospital investigated testosterone and estradiol levels in 400 healthy men, 20 to 50 years of age. To control hormone levels, the researchers first gave the participants injections of a drug that suppressed their normal testosterone and estradiol production. The men were randomly assigned to 5 groups that received different amounts (from 0 to 10 grams) of a topical 1% testosterone gel daily for 16 weeks. Half of the participants were also given a drug to block testosterone from being converted to estradiol.

Nutrient timing is a hot topic, especially for athletes and anyone looking for that extra edge in the gym or in body transformation. Part of this stems from science showing that the timing of carbohydrate consumption does influence important aspects, such as glycogen replenishment (and in limited cases, muscle protein synthesis). The other side is practical: You want the most bang for your buck when it comes to the nutritional products and supplements you purchase.
^ Jump up to: a b Wallimann T, Wyss M, Brdiczka D, Nicolay K, Eppenberger HM (January 1992). "Intracellular compartmentation, structure and function of creatine kinase isoenzymes in tissues with high and fluctuating energy demands: the 'phosphocreatine circuit' for cellular energy homeostasis". The Biochemical Journal. 281 ( Pt 1) (Pt 1): 21–40. doi:10.1042/bj2810021. PMC 1130636. PMID 1731757.
In 1990, professional wrestling promoter Vince McMahon announced that he was forming a new bodybuilding organization named the World Bodybuilding Federation (WBF). McMahon wanted to bring WWF-style showmanship and bigger prize money to the sport of bodybuilding. A number of IFBB stars were recruited but the roster was never very large and featured the same athletes competing; the most notable winner and first WBF champion was Gary Strydom. McMahon formally dissolved the WBF in July 1992. Reasons for this reportedly included lack of income from the pay-per-view broadcasts of the contests, slow sales of the WBF's magazine Bodybuilding Lifestyles (later WBF Magazine), and the expense of paying multiple six-figure contracts while producing two TV shows and a monthly magazine.
Some protein powders are loaded with junk. We recommend this grass-fed protein isolate because it is a non-GMO product and contains no artificial sweeteners. It is a US-based product, and the whey protein is cultivated from American cows. With 28 grams of protein in one scoop, one spoonful of this powder may provide the equivalent protein profile of a whole meal. What’s even better is that one scoop is only 120 calories. This powder gives you quite a bit of protein for minimal calories, keeping you lean.
"Eating well" is tough to objectively quantify. One can eat "well" but that doesn't necessarily mean that you are eating enough to build muscle or recover adequately from workouts. Also, taking protein shakes doesn't guarantee that one will start to accrue massive slabs of lean body mass. Muscle anabolism is a fairly complex metabolic process which has a number of contributing factors at the cellular level and can't be reduced to a single supplement or dietary component.
One case study exists of a man with focal segmental glomerulosclerosis who experienced an accelerated rate of GFR decline during supplementation (5g thrice daily for loading, then a 2g maintenance for seven weeks) which was partially reversed upon supplement cessation. This was deemed strong circumstantial evidence, and the brand of supplement was not named.[616] Elsewhere, interstitial nephritis associated with creatine supplementation has been reported in a man, although symptoms arose four weeks after supplementation started with no evidence to support correlation.[617] Some studies involving athletes and various dietary supplements have attempted to draw a correlation with creatine and cases of rhabdomyolysis.[618][619][620][621] Finally, one study in a diabetic person ingesting both metformin and creatine resulting in metabolic acidosis has attempted to place causation on creatine, but it did not establish causation or circumstantial evidence.[622]

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.