The majority of creatine in the human body is in two forms, either the phosphorylated form making up 60% of the stores or in the free form which makes up 40% of the stores. The average 70 kg young male has a creatine pool of around 120-140 g which varies between individuals [10,11] depending on the skeletal muscle fiber type [1] and quantity of muscle mass [11]. The endogenous production and dietary intake matches the rate of creatinine production from the degradation of phosphocreatine and creatine at 2.6% and 1.1%/d respectively. In general, oral creatine supplementation leads to an increase of creatine levels within the body. Creatine can be cleared from the blood by saturation into various organs and cells or by renal filtration [1].
^ "The History of Weightlifting". USA Weightlifting. United States Olympic Committee. Archived from the original on 7 July 2013. Retrieved 3 September 2018. The genealogy of lifting traces back to the beginning of recorded history where man's fascination with physical prowess can be found among numerous ancient writings. A 5,000-year-old Chinese text tells of prospective soldiers having to pass lifting tests.
Endogenous serum or plasma creatine concentrations in healthy adults are normally in a range of 2–12 mg/L. A single 5 g (5000 mg) oral dose in healthy adults results in a peak plasma creatine level of approximately 120 mg/L at 1–2 hours post-ingestion. Creatine has a fairly short elimination half-life, averaging just less than 3 hours, so to maintain an elevated plasma level it would be necessary to take small oral doses every 3–6 hours throughout the day. After the "loading dose" period (1–2 weeks, 12–24 g a day), it is no longer necessary to maintain a consistently high serum level of creatine. As with most supplements, each person has their own genetic "preset" amount of creatine they can hold. The rest is eliminated as waste. A typical post-loading dose is 2–5 g daily.[52][53][54]
It can be hard not to compare yourself to Schwarzenegger, with his action-star movie career, his stint as a president-appointed fitness ambassador and his election as governor of California. Chang said that Heath’s personality, including his charisma and outspokenness, is similar to that of Schwarzenegger, who is still omnipresent and beloved in the sport.
Although it does not appear to influence baseline antioxidant enzymes (measured in red blood cells), one week of creatine loading in otherwise healthy young adults has increased red blood cell (RBC) content of the superoxide dismutase (SOD) enzyme in response to a sprint test by 8.1% immediately after exercise. This was no longer detectable after an hour since placebo increased to match.[299] Glutathione and catalase are unaffected.[299]
Creatine supplementation at 300mg/kg for one week (loading with no maintenance) in youth subject to six repeated 35m sprints (10s rest, known as the Running-based Anaerobic Sprint Test or RAST) noted that the increased average and peak power output seen in creatine was not met with a reduction in fatigue, although there was an attenuation in inflammation from exercise (TNFα and CRP).[299]
HMB supplementation is claimed to build muscle size and strength and promote fat loss in conjunction with a strength program. Studies of HMB have shown some benefit to strength athletes in building muscle bulk but the benefits are relatively small and the cost of HMB is high. The effective dose seems to be 3 grams/day divided into 1 gram three times a day. Probably not worth taking. Beta-alanine is the new guy on the block and has not been evaluated sufficiently in my view. It may provide some advantage in high-intensity sports like weight training but it’s much too early to know that it does. Some early studies are flawed. Save your money or try creatine instead.

In today's extra-large society, we tend to focus on the admirable guys who train hard and switch up their diet to transform their bodies by losing weight. We highlight their quests to lead healthier lives every chance we get — but there's another side of the wellness scale that can be just as difficult, depending on your body's makeup: Gaining mass and muscle.
Brain injury. Early research shows that taking creatine by mouth daily for 7 days increases the ability to exercise by increasing lung function in people with a spinal cord injury. However, other research shows that creatine does not improve wrist muscle or hand function. Early research also shows that taking creatine by mouth daily for 6 months reduces amnesia following a traumatic brain injury in children.
Any exercise that works and/or stretches the buttocks is suitable, for example lunges, hip thrusts, climbing stairs, fencing, bicycling, rowing, squats, arabesque, aerobics, and various specific exercises for the bottom. Weight training exercises which are known to significantly strengthen the gluteal muscles include the squat, deadlift, leg press, any other movements involving external hip rotation and hip extension.

These effects are secondary to creatine being a source of phosphate groups and acting as an energy reserve. The longer a cell has energy, the longer it can preserve the integrity of the cell membrane by preserving integrity of the Na+/K+-ATPase and Ca2+-ATPase enzymes.[241][235][236] Preserving ATP allows creatine to act via a nongenomic response (not requiring the nuclear DNA to transcribe anything), and appears to work secondary to MAPK and PI3K pathways.[226]
Put simply, "strength training means using resistance to create work for your muscles," says Hannah Davis, C.S.C.S. and author of Operation Bikini Body. So even if your mind jumps straight to those hardcore machines and massive weights, there are a lot of ways to create this resistance that require minimal equipment (or none at all). Bodyweight workouts can be an incredibly effective way to strength train. Squats and push-ups FTW. You can also use tools like dumbbells, medicine balls, TRX bands, resistance bands, kettlebells, and slider disks, to help get the job done, explains Davis. But if that sounds like gibberish don't worry about it. Keep it simple and focus on equipment-free routines first. No matter what you do, the most important thing is to find something that challenges you, says Davis. 

Research shows that starting as early as age 30, the body begins to slowly lose muscle mass, with women losing up to 15 percent of their total-body muscle per decade by age 50. Apart from declines in strength, that declining muscle mass comes with a declining metabolism, Emilia Ravski, D.O., a sports medicine specialist with Hoag Orthopedic Institute in California, tells SELF. This decline in metabolic rate is actually one driving factor of the weight that women generally tend to put on after we naturally hit our peak muscle levels in our 20s, research from Tufts University suggests.
^ "Popular sports supplements contain meth-like compound". USA Today. October 25, 2013. Cohen said researchers informed the FDA in May about finding the new chemical compound in Craze. The team found the compound — N,alpha-diethylphenylethylamine — has a structure similar to methamphetamine, a powerful, highly addictive, illegal stimulant drug. They believe the new compound is likely less potent than methamphetamine but greater than ephedrine.
Jager et al [60] observed 1.17 and 1.29 greater peak plasma creatine concentration 1 hour after ingesting creatine pyruvate compared to isomolar amount of CM and creatine citrate respectively. However time to peak concentration, and velocity constants of absorption and elimination, was the same for all three forms of creatine. Although not measured in this study it is questionable that these small differences in plasma creatine concentrations would have any effect on the increase of muscle creatine uptake. Jäger et al [61] investigated the effects of 28-days of creatine pyruvate and citrate supplementation on endurance capacity and power measured during an intermittent handgrip (15 s effort per 45s rest) exercise in healthy young athletes. The authors used a daily dose protocol with the intention to slowly saturate muscle creatine stores. Both forms of creatine showed slightly different effects on plasma creatine absorption and kinetics. The two creatine salts significantly increased mean power but only pyruvate forms showed significant effects for increasing force and attenuating fatigability during all intervals. These effects can be attributed to an enhanced contraction and relaxation velocity as well as a higher blood flow and muscle oxygen uptake. On the other hand, the power performance measured with the citrate forms decreases with time and improvements were not significant during the later intervals. In spite of these positive trends further research is required about the effects of these forms of creatine as there is little or no evidence for their safety and efficacy. Furthermore the regularity status of the novel forms of creatine vary from country to country and are often found to be unclear when compared to that of CM [62].
Spero Karas, MD, assistant professor of orthopaedics in the division of sports medicine at Emory University, says that testosterone, the male hormone responsible for muscle growth, maxes out between the ages of 16 and 18. It reaches a plateau during the 20s and then begins to decline. As a result, muscle building after the adolescent years can be challenging, he says.
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.