In addition to the BBB, SLC6A8 is also expressed on neurons and oligodendrocytes, but is relatively absent from astrocytes, including the astrocytic feet which line 98% of the BBB. Creatine can still be transported into astrocytes (as well as cerebellar granule cells) via SLC6A8, as incubation with an SLC6A8 inhibitor prevents accumulation in vitro. It seems to be less active in a whole brain model, relative to other brain cells.
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.
In regard to liver fat buildup (steatosis), which is normally associated with reduced availability of S-adenosyl methionine and a suppression in expression of genes involved in fatty acid oxidation (PPARα and CPT1), creatine supplementation at 1% of the rat diet alongside a diet that induces fatty liver is able to fully prevent (and nonsignificantly reduce relative to the control given standard diets) the aforementioned changes and the state of steatosis, as well as changes in serum biomarkers (glucose and insulin) that accompany steatosis.
The main storage area of creatine in the human body is the skeletal (contractile) muscle, which holds true for other animals. Therefore, consumption of skeletal muscle (meat products) is the main human dietary source of creatine. Since vegetarians and vegans lack the main source of dietary creatine intake, which has been estimated to supply half of the daily requirements of creatine in normal people, both vegetarians and vegans have been reported to have lower levels of creatine. This also applies to other meat-exclusive nutrients, such as L-Carnitine.
On January 16, 1904, the first large-scale bodybuilding competition in America took place at Madison Square Garden in New York City. The competition was promoted by Bernarr Macfadden, the father of physical culture and publisher of original bodybuilding magazines such as Health & Strength. The winner was Al Treloar, who was declared "The Most Perfectly Developed Man in the World". Treloar won a $1,000 cash prize, a substantial sum at that time. Two weeks later, Thomas Edison made a film of Treloar's posing routine. Edison had also made two films of Sandow a few years before. Those were the first three motion pictures featuring a bodybuilder. In the early 20th century, Macfadden and Charles Atlas continued to promote bodybuilding across the world. Alois P. Swoboda was an early pioneer in America.
Naturo Nitro Creatine Chrome could be an interesting choice for women. It’s actually magnesium creatine chelate, a type of creatine that may help to improve performance without increasing water weight. We don’t have a lot of studies on it just yet, but the research we do have suggests it could potentially be a good choice for women who want to improve performance without experiencing the “bloat” of regular creatine.
These supplements can vary considerably from product to product in ingredients, serving sizes, and more. But the goal of each of them is generally quite similar. Most bodybuilding supplements are designed to help stimulate new muscle growth, cut away excess fat, and improve the recovery process so that you can get the most out of each trip to the gym.
One pilot study using 150mg/kg creatine monohydrate for a five day loading phase followed by maintenance (60mg/kg) for the remainder of the five weeks noted that supplementation was associated with fewer muscle symptoms and complaints alongside improved muscular function, yet a later trial trying to replicate the obsevations using 150mg/kg daily for five weeks noted the opposite, that creatine supplementation exacerbated symptoms.