Gualano, B., de, Salles Painelli, V, Roschel, H., Lugaresi, R., Dorea, E., Artioli, G. G., Lima, F. R., da Silva, M. E., Cunha, M. R., Seguro, A. C., Shimizu, M. H., Otaduy, M. C., Sapienza, M. T., da Costa, Leite C., Bonfa, E., and Lancha Junior, A. H. Creatine supplementation does not impair kidney function in type 2 diabetic patients: a randomized, double-blind, placebo-controlled, clinical trial. Eur.J.Appl.Physiol 2011;111:749-756. View abstract.
Athletic performance. Creatine seems to help improve rowing performance, jumping height, and soccer performance in athletes. But the effect of creatine on sprinting, cycling, or swimming performance varies. The mixed results may relate to the small sizes of the studies, the differences in creatine doses, and differences in test used to measure performance. Creatine does not seem to improve serving ability in tennis players.
Chin-Ups. The chin-up is the easiest way to determine someone’s relative strength. If you can knock out sets of bench with your bodyweight but can’t perform at least 5 bodyweight chin-ups then it’s time to re-evaluate your priorities. Chin-ups are an excellent mass builder for the lats, biceps, and upper back so they should take the place of machine variations like lat pulldowns whenever possible.
In a study on Alpha-Lipoic Acid, 1,000mg of ALA paired with 100g sucrose and 20g creatine monohydrate was more effective in increasing muscular creatine levels relative to creatine alone and creatine combined with sucrose. This apparent augmentation of creatine uptake into muscle cells was used alongside a loading period. Another study investigating a nutrient mixture (150g glucose, 20g creatine, 2g/kg bodyweight glycerol) on heat tolerance in trained athletes found that replacing one third (50g) of the glucose with 1g ALA resulted in no significant differences between groups (in regard to heat tolerance and cardiovascular performance) despite the reduction of 50g carbohydrate.
In the early 2000s, the IFBB was attempting to make bodybuilding an Olympic sport. It obtained full IOC membership in 2000 and was attempting to get approved as a demonstration event at the Olympics, which would hopefully lead to it being added as a full contest. This did not happen and Olympic recognition for bodybuilding remains controversial since many argue that bodybuilding is not a sport.
In regard to bioenergetics, phosphorylated cyclocreatine appears to have less affinity for the creatine kinase enzyme than phosphorylated creatine in terms of donating the high energy phosphate group (about 160-fold less affinity) despite the process of receiving phosphorylation being similar. When fed to chickens, phosphorylated cyclocreatine can accumulate up to 60mM in skeletal muscle, which suggests a sequestering of phosphate groups before equilibrium is reached. Cyclocreatine still has the capacity to donate phosphate, however, as beta-adrenergic stimulated skeletal muscle (which depletes ATP and glycogen) exhibits an attenuation of glycogen depletion (indicative of preservation of ATP) with phosphocreatine.
In the 1970s, bodybuilding had major publicity thanks to the appearance of Arnold Schwarzenegger, Franco Columbu, Lou Ferrigno, and others in the 1977 docudrama Pumping Iron. By this time, the IFBB dominated the competitive bodybuilding landscape and the Amateur Athletic Union (AAU) took a back seat. The National Physique Committee (NPC) was formed in 1981 by Jim Manion, who had just stepped down as chairman of the AAU Physique Committee. The NPC has gone on to become the most successful bodybuilding organization in America and is the amateur division of the IFBB. The late 1980s and early 1990s saw the decline of AAU-sponsored bodybuilding contests. In 1999, the AAU voted to discontinue its bodybuilding events.
A: Let your symptoms be your guide. A slight sore throat or runny nose may require you to back off for a day or two but don’t confine yourself to your bed and assume the worst. However, you must also remember that prolonged, intense exercise can decrease immune function and make you more susceptible to bacterial and viral based sickness so it's equally as important to listen to your body and respond accordingly.
One study on 27 otherwise healthy men supplementing creatine (0.3g/kg loading for a week, 0.05g/kg thereafter for 8 weeks) with a thrice weekly exercise regiment noted that alongside greater increase in lean mass and power relative to placebo at 4 and 8 weeks, myostatin in serum decreased to a greater extent with creatine (around 17% at 8 weeks, derived from graph) than it did with placebo (approximately 7%). Increases in GASP-1, a serum protein that inhibits the actions of myostatin by directly binding to it, were not different between groups.
^ Spillane M, Schoch R, Cooke M, Harvey T, Greenwood M, Kreider R, Willoughby DS (February 2009). "The effects of creatine ethyl ester supplementation combined with heavy resistance training on body composition, muscle performance, and serum and muscle creatine levels". Journal of the International Society of Sports Nutrition. 6 (1): 6. doi:10.1186/1550-2783-6-6. PMC 2649889. PMID 19228401.
While many of the claims are based on scientifically based physiological or biochemical processes, their use in bodybuilding parlance is often heavily colored by bodybuilding lore and industry marketing and as such may deviate considerably from traditional scientific usages of the terms. In addition, ingredients listed have been found at times to be different from the contents. In 2015, Consumer Reports reported unsafe levels of arsenic, cadmium, lead and mercury in several of the protein powders that were tested.
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.
Creatine is classified as a "dietary supplement" under the 1994 Dietary Supplement Health and Education Act and is available without a prescription. Creatine is not subjected to FDA testing, and the purity and hygienic condition of commercial creatine products may be questionable . A 1998 FDA report lists 32 adverse creatine-associated events that had been reported to FDA. These include seizure, vomiting, diarrhea, anxiety, myopathy, cardiac arrhythmia, deep vein thromboses and death. However, there is no certainty that a reported adverse event can be attributed to a particular product . A recent survey of 28 male baseball players and 24 male football players, ages 18 to 23, found that 16 (31%) experienced diarrhea, 13 (25%) experienced muscle cramps, 7 (13%) reported unwanted weight gain, 7 (13%) reported dehydration, and 12 reported various other adverse effects .
Research shows that strength training is especially effective at raising EPOC. That’s because, generally speaking, strength-training sessions cause more physiological stress to the body compared to cardiovascular exercise, even higher-intensity cardio intervals. However, it’s worth noting that overall exercise intensity is what makes the biggest impact on EPOC. So squats, deadlifts, and bench presses with heavy weights are going to be much more effective at raising EPOC compared to bicep curls and triceps extensions with light weights.