Due to this relative deficiency-state in vegetarians and vegans, some aspects of creatine supplementation are seen as more akin to normalizing a deficiency, rather than providing the benefits of supplementation. In young vegetarians, but not omnivores, creatine supplementation can enhance cognition. The increased gain in lean mass may be more significant in vegetarians, relative to omnivores. Supplementation of creatine in vegetarians appears to normalize the gap in storage between vegetarians and omnivores. This is possibly related to a correlation seen in survey research, where vegetarianism and veganism appear to be more commonly affected by some mental disorders like anxiety and depression.
Consuming sufficient high-quality protein is essential for building muscle. Current recommendations are to consume a minimum of 0.8g of protein for each kg of body weight, however, this is really only applicable to the average sedentary individual. Current evidence shows that to support muscle development, protein intake is the key, therefore the recommended 0.8g per kg should be increased to 1.5-2.0g of protein per kg of body weight. For an 80 kg individual, that would equate to 120-160 grams of protein per day.
Several review studies assessing the safety of creatine supplementation tend to make note of increases in formaldehyde and possible carcinogenic results. Specifically, creatine is metabolized into an intermediate called methylamine, which can be converted to formaldehyde by the SSAO enzyme. An increase in urinary formaldehyde has been noted in youth given 21g of creatine for one week, during which both methylamine (820% increase) and formaldehyde (350%) were increased, relative to control. However, a more prolonged study using 300mg/kg (loading dose of around 20g) in adults for ten weeks failed to replicate these effects.
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.
Creatine is a hydrophilic polar molecule that consists of a negatively charged carboxyl group and a positively charged functional group . The hydrophilic nature of creatine limits its bioavailability . In an attempt to increase creatines bioavailability creatine has been esterified to reduce the hydrophilicity; this product is known as creatine ethyl ester. Manufacturers of creatine ethyl ester promote their product as being able to by-pass the creatine transporter due to improved sarcolemmal permeability toward creatine . Spillane et al  analyzed the effects of a 5 days loading protocol (0.30 g/kg lean mass) followed by a 42 days maintenance phase (0.075 g/kg lean mass) of CM or ethyl ester both combined with a resistance training program in 30 novice males with no previous resistance training experience. The results of this study  showed that ethyl ester was not as effective as CM to enhance serum and muscle creatine stores. Furthermore creatine ethyl ester offered no additional benefit for improving body composition, muscle mass, strength, and power. This research did not support the claims of the creatine ethyl ester manufacturers.
Many trainees like to cycle between the two methods in order to prevent the body from adapting (maintaining a progressive overload), possibly emphasizing whichever method more suits their goals; typically, a bodybuilder will aim at sarcoplasmic hypertrophy most of the time but may change to a myofibrillar hypertrophy kind of training temporarily in order to move past a plateau. However, no real evidence has been provided to show that trainees ever reach this plateau, and rather was more of a hype created from "muscular confusion".[clarification needed]
Despite a possible decreasing creatine content in the muscles when maintenance is deemed suboptimal, the overall retention of weight and lean mass is merely additive over time. This is thought to be due to increases in skeletal muscle production (increase in body weight) compensating for the progressive declines in water and glycogen content (decreases in body weight).
Creatine supplementation appears to attenuate decreases in GLUT4 expression seen with immobility and may increase GLUT4 expression during exercise. While it seems capable of increasing GLUT4 during resting conditions, it has failed to reach significance, suggesting that creatine supplementation works best with some stimuli associated with exercise.
Creatine was first identified in 1832 when Michel Eugène Chevreul isolated it from the basified water-extract of skeletal muscle. He later named the crystallized precipitate after the Greek word for meat, κρέας (kreas). In 1928, creatine was shown to exist in equilibrium with creatinine. Studies in the 1920s showed that consumption of large amounts of creatine did not result in its excretion. This result pointed to the ability of the body to store creatine, which in turn suggested its use as a dietary supplement.
Children: Creatine is POSSIBLY SAFE in children when taken by mouth appropriately. Creatine 3-5 grams daily for 2-6 months has been taken safely in children 5-18 years of age. Creatine 2 grams daily for 6 months has been taken safely in children 2-5 years of age. Additionally, creatine 0.1-0.4 grams/kg daily for up to 6 months has been taken safely in both infants and children.
It is suggested [16,37] that another mechanism for the effect of creatine could be enhanced muscle glycogen accumulation and GLUT4 expression, when creatine supplementation is combined with a glycogen depleting exercise. Whereas it has been observed  that creatine supplementation alone does not enhance muscle glycogen storage. Hickner et al  observed positive effects of creatine supplementation for enhancing initial and maintaining a higher level of muscle glycogen during 2 hours of cycling. In general, it is accepted that glycogen depleting exercises, such as high intensity or long duration exercise should combine high carbohydrate diets with creatine supplementation to achieve heightened muscle glycogen stores .
Creatine supplementation may be able to enhance lifespan, secondary to increasing intracellular carnosine stores. Carnosine is the metabolic compound formed from beta-alanine supplementation, and in a mouse-model for premature aging (senescence-accelerated premature aging, SAMP8) creatine supplementation without any beta-alanine has been shown to increase cellular carnosine stores. That being said, the aforemented SAMP8 study noted an increase in carnosine levels at middle age, but not old age in the mice. A human study using 20g of creatine for one week in otherwise healthy people failed to find an increase in intracellular carnosine stores.
In people with COPD given either glucose placebo (40.7g) or creatine supplementation (5.7g creatine with 35g glucose) thrice daily for two weeks followed by a single dose for ten weeks, supplementation was associated with improvements in muscular strength and endurance, but not cardiovascular exercise potential. A later trial of larger power using a loading phase of 22g creatine with a maintenance phase of 3.76g during rehabilitative exercise failed to replicate the improvements in skeletal muscle performance despite increased body weight seen with creatine, and the failure to improve cardiovascular performance during aerobic exercise seen in both aforementioned studies has been replicated elsewhere after eight weeks supplementation, during which muscular performance was, again, unaffected.
Now that you've got the training part down, it's time to stretch it out. (Can you say ahhh?) Stretching while your muscles are warm can help improve your flexibility, says Davis, not to mention it just feels phenomenal after you've pushed yourself hard. A light cool-down is also great for calming the nervous system. While dynamic stretches should be your go-to during a warm-up, the cool-down is where static stretching comes in—this means holding a stretch for 20-30 seconds. These four passive stretches will do nicely.
Heath says to consume 1.25-2 grams of protein per pound of body weight for growth and he never exceeds a 1:1 meals to protein shake ratio, meaning if he has 3 shakes, he’ll have 3 meals. He suggests if you’re going to drink protein shakes, drink two and have four meals. Also, increase your protein consumption and decrease carbs to look lean. “Once I got to a certain size, I wanted to get leaner so I got to 50% protein, 30% carbs and 20% protein.”
Despite the popularity of creatine among young people, there has been very little research conducted in children under age 18. Of those studies, a few have suggested a positive effect but the overall evidence is inconclusive. In one study, teenage swimmers performed better after taking creatine; in another study, it helped high school soccer players sprint, dribble, and jump more effectively.
It’s important to remember that since everybody is different, these estimates are just that. How the numbers work out for each person will definitely vary. So many factors—like genetics, hormones, sleep, and diet—can change the rate at which our bodies burn calories. And some people may have a harder time than others when it comes losing fat or gaining muscle—again, there are so many factors at play and our body chemistries are all different. Strength training is important for many, many, many other reasons (more on that later), but if you’re looking to increase your metabolism, it’s important to have realistic expectations and know that strength training can make a difference, but probably won’t drastically affect how many calories you burn from one day to the next.
In regard to the blood brain barrier (BBB), which is a tightly woven mesh of non-fenestrated microcapillary endothelial cells (MCECs) that prevents passive diffusion of many water-soluble or large compounds into the brain, creatine can be taken into the brain via the SLC6A8 transporter. In contrast, the creatine precursor (guanidinoacetate, or GAA) only appears to enter this transporter during creatine deficiency. More creatine is taken up than effluxed, and more GAA is effluxed rather than taken up, suggesting that creatine utilization in the brain from blood-borne sources is the major source of neural creatine. However, “capable of passage” differs from “unregulated passage” and creatine appears to have tightly regulated entry into the brain in vivo. After injecting rats with a large dose of creatine, creatine levels increased and plateaued at 70uM above baseline levels. These baseline levels are about 10mM, so this equates to an 0.7% increase when superloaded. These kinetics may be a reason for the relative lack of neural effects of creatine supplementation in creatine sufficient populations.