When testosterone and endorphins in ejaculated semen meet the cervical wall after sexual intercourse, females receive a spike in testosterone, endorphin, and oxytocin levels, and males after orgasm during copulation experience an increase in endorphins and a marked increase in oxytocin levels. This adds to the hospitable physiological environment in the female internal reproductive tract for conceiving, and later for nurturing the conceptus in the pre-embryonic stages, and stimulates feelings of love, desire, and paternal care in the male (this is the only time male oxytocin levels rival a female's).[citation needed]
Creatine is used up as energy during high intensity exercise. Due to this usage, the amount of glucose required from glycogen is decreased a bit. This both preserves glycogen concentrations in skeletal muscle and reduces lactate production, which is produced when glucose is oxidized for energy. There do not appear to be any alterations in the bioenergetic status of muscle cells during low to moderate intensity exercise.
Squats target both your inner and outer thighs. Use a barbell heavy enough to challenge your muscles but light enough that you can still control your form. Hold it behind your head with your feet shoulder-width apart. Tighten your core, then squat down as far as comfortable. There should be no knee or back pain. As you come back up, raise your hips and chest together.
Whey, the liquid remaining after milk has been curdled and strained, is rapidly digested and absorbed and has a remarkable ability to stimulate muscle protein synthesis (Hayes & Cribb, 2008). Whey is available in three varieties — whey protein powder, whey protein concentrate, whey protein isolate — and all provide high levels of the essential and branched chain amino acids, vitamins and minerals.
When females have a higher baseline level of testosterone, they have higher increases in sexual arousal levels but smaller increases in testosterone, indicating a ceiling effect on testosterone levels in females. Sexual thoughts also change the level of testosterone but not level of cortisol in the female body, and hormonal contraceptives may affect the variation in testosterone response to sexual thoughts.[51]
Incubation of a β-cell with additional creatine (5-10mM), even at saturated concentrations of glucose, is able to further increase insulin secretion in response to glucose, specifically as the leucine metabolite 2-ketoisocaproic acid, potassium, and a potassium channel blocker were all ineffective.[494] This has been found to occur in rats given 2% of the diet as creatine[345] but has since failed in humans given 5g of creatine.[351]
A testicular action was linked to circulating blood fractions – now understood to be a family of androgenic hormones – in the early work on castration and testicular transplantation in fowl by Arnold Adolph Berthold (1803–1861).[182] Research on the action of testosterone received a brief boost in 1889, when the Harvard professor Charles-Édouard Brown-Séquard (1817–1894), then in Paris, self-injected subcutaneously a "rejuvenating elixir" consisting of an extract of dog and guinea pig testicle. He reported in The Lancet that his vigor and feeling of well-being were markedly restored but the effects were transient,[183] and Brown-Séquard's hopes for the compound were dashed. Suffering the ridicule of his colleagues, he abandoned his work on the mechanisms and effects of androgens in human beings.

In 1927, the University of Chicago's Professor of Physiologic Chemistry, Fred C. Koch, established easy access to a large source of bovine testicles — the Chicago stockyards — and recruited students willing to endure the tedious work of extracting their isolates. In that year, Koch and his student, Lemuel McGee, derived 20 mg of a substance from a supply of 40 pounds of bovine testicles that, when administered to castrated roosters, pigs and rats, remasculinized them.[184] The group of Ernst Laqueur at the University of Amsterdam purified testosterone from bovine testicles in a similar manner in 1934, but isolation of the hormone from animal tissues in amounts permitting serious study in humans was not feasible until three European pharmaceutical giants—Schering (Berlin, Germany), Organon (Oss, Netherlands) and Ciba (Basel, Switzerland)—began full-scale steroid research and development programs in the 1930s.

The basic principles of weight training are essentially identical to those of strength training, and involve a manipulation of the number of repetitions (reps), sets, tempo, exercise types, and weight moved to cause desired increases in strength, endurance, and size. The specific combinations of reps, sets, exercises, and weights depends on the aims of the individual performing the exercise.
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 government to the manufacturer and supplements no longer required approval from the U.S. Food and Drug Administration (FDA) before distributing product. 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.[6]
1. Are you tracking calories? Doesn't have to be religiously but one should have a general idea of where they're at if the goal is mass gain and things have stalled. I'm not talking about weighing every gram of food you put in your mouth and meticulously logging your life on MyFitnessPal. As long as you're aware (within 100-200 calories) of what's going in, you should have an idea of what to adjust.
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.
In males, the testosterone test can help find the reason for sexual problems, like reduced sex drive or erectile dysfunction. If you’re having a hard time getting your partner pregnant, the test can tell if your blood testosterone level is low. It can also screen for problems with the hypothalamus or pituitary gland. This controls how much testosterone your body makes.
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.

Some other cytokines and hormones may increase the receptor activity. These include growth hormone (GH) which acts upon the growth hormone receptor (GHR)[166][167] to stimulate c-Src[168][169] which directly increases the activity of the CrT via phosphorylation. This is known to occur with the 55kDa version of c-Src but not the 70kDa version and requires CD59 alongside c-Src.[170]
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]
Some other cytokines and hormones may increase the receptor activity. These include growth hormone (GH) which acts upon the growth hormone receptor (GHR)[166][167] to stimulate c-Src[168][169] which directly increases the activity of the CrT via phosphorylation. This is known to occur with the 55kDa version of c-Src but not the 70kDa version and requires CD59 alongside c-Src.[170]
You’ll Feel Better: Not only will you find yourself with more energy and confidence, less stress and anxiety, and a better overall mood, but you’ll actually begin to think better (resistance training has been proven to help increase cognitive function). And while training too close to bedtime can be a bad idea, exercising earlier in the day has been proven to help prevent sleep apnea and insomnia. I even improved my posture – when I started lifting, I was 5’4”.  Now I’m 5’5.5”.

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]
A previous meta-analysis [28] reported an overall creatine supplementation effect size (ES) of 0.24 ± 0.02 for activities lasting ≤30 s. (primarily using the ATP- phosphocreatine energy system). For this short high-intensity exercise, creatine supplementation resulted in a 7.5 ± 0.7% increase from base line which was greater than the 4.3 ± 0.6% improvement observed for placebo groups. When looking at the individual selected measures for anaerobic performance the greatest effect of creatine supplementation was observed on the number of repetitions which showed an ES of 0.64 ± 0.18. Furthermore, an increase from base line of 45.4 ± 7.2% compared to 22.9 ± 7.3% for the placebo group was observed. The second greatest ES was on the weight lifted at 0.51 ± 0.16 with an increase from base line of 13.4 ± 2.7% for the placebo group and 24.7 ± 3.9% for the creatine group. Other measures improved by creatine with a mean ES greater than 0 were for the amount of work accomplished, weight lifted, time, force production, cycle ergometer revolutions/min and power. The possible effect of creatine supplementation on multiple high intensity short duration bouts (<30 s) have shown an ES not statistically significant from 0. This would indicate that creatine supplementation might be useful to attenuate fatigue symptoms over multiple bouts of high-intensity, short duration exercise. The ES of creatine on anaerobic endurance exercise (>30 – 150s), primarily using the anaerobic glycolysis energy system, was 0.19 ± 0.05 with an improvement from baseline of 4.9 ± 1.5 % for creatine and -2.0 ± 0.6% for the placebo. The specific aspects of anaerobic endurance performance improved by creatine supplementation were work and power, both of which had a mean ES greater than 0. From the findings of this previous meta-analysis [28] it would appear that creatine supplementation has the most pronounced effect on short duration (<30s) high intensity intermittent exercises.
While it'’s okay to chow down on the occasional fast-food choice for convenience, a mass-gain program isn'’t an excuse to gorge on pizza and chocolate sundaes. “"Rebuilding muscle tissue broken down by training requires energy -— in other words, calories,"” says bodybuilding nutritional guru Chris Aceto. "“But many people, including many nutritionists, overestimate the energy needs for gaining mass, encouraging extreme high-calorie intakes. This often leads to an increase in bodyfat, making you bigger, for sure, but also leaving you fat." In general, aim for 300-500 more calories every day than your body burns through exercise and normal functioning (multiply bodyweight by 17). And that'’s divided among six meals a day.
The structure of cyclocreatine is fairly flat (planar), which aids in passive diffusion across membranes. It has been used with success in an animal study, where mice suffered from a SLC6A8 (creatine transporter at the blood brain barrier) deficiency, which is not responsive to standard creatine supplementation.[97] This study failed to report increases in creatine stores in the brain, but noted a reduction of mental retardation associated with increased cyclocreatine and phosphorylated cyclocreatine storages.[97] As demonstrated by this animal study and previous ones, cyclocreatine is bioactive after oral ingestion[97][98] and may merely be a creatine mimetic, able to phosphorylate ADP via the creatine kinase system.[97]
In the modern bodybuilding industry, the term "professional" generally means a bodybuilder who has won qualifying competitions as an amateur and has earned a "pro card" from their respective organization. Professionals earn the right to compete in competitions that include monetary prizes. A pro card also prohibits the athlete from competing in federations other than the one from which they have received the pro card.[12] Depending on the level of success, these bodybuilders may receive monetary compensation from sponsors, much like athletes in other sports.
Safety. Excess quantities of antioxidants may produce a ‘pro-oxidant’ effect, which is the opposite of what you would take these supplements for. The Australian Institute of Sport recommends that antioxidant vitamin supplements only be taken for a period of a few weeks while the body adjusts to stressful circumstances. Excess vitamin C may promote excess iron absorption, which may not be healthy for everyone.
Do you know what happens when a person attempts to build muscle faster than they legitimately can? They fail, and then they wonder why it’s not working as quickly as they thought it would. From there, they’ll jump from workout to workout, diet to diet and useless supplement to useless supplement in the hopes of finally finding the missing link that will make it happen. But they’re never going to find it. They’ll just keep wasting their time, effort and money searching for something that doesn’t exist.