Bird, L. M., Tan, W. H., Bacino, C. A., Peters, S. U., Skinner, S. A., Anselm, I., Barbieri-Welge, R., Bauer-Carlin, A., Gentile, J. K., Glaze, D. G., Horowitz, L. T., Mohan, K. N., Nespeca, M. P., Sahoo, T., Sarco, D., Waisbren, S. E., and Beaudet, A. L. A therapeutic trial of pro-methylation dietary supplements in Angelman syndrome. Am J Med Genet.A 2011;155A(12):2956-2963. View abstract.
Beta-alanine is a naturally occurring non-essential amino acid that comes into the body through foods that are rich in protein. The performance-enhancing aspect of beta-alanine (BA) is due to its ability to increase intra-muscular levels of carnosine. Increasing beta-alanine through supplementation may raise carnosine levels by over 60 percent in as quickly as four weeks.
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.
While some supplements may in fact provide health benefits, generally speaking, consumers should purchase and use these products cautiously as they are not closely regulated by the Food and Drug Administration (FDA). Also, bodybuilders are advised to discuss supplementation plans with a registered dietitian or primary care physician prior to use to optimize effectiveness and minimize potential harmful consequences.
You see, there is only so much muscle that the human body is capable of building in a given period of time. So, if you supply your body with MORE calories than it’s actually capable of putting towards the process of building new muscle… it’s not going to magically lead to additional muscle being built. It’s just going to lead to additional fat being gained.
When looking specifically at human studies, there has been a failure of creatine supplementation to induce or exacerbate kidney damage in people with amyotrophic lateral sclerosis (ALS). Subjects do not experience kidney damage for up to or over a year’s worth of supplementation in the 5-10g range. Postmenopausal women, people with type II diabetes, people on hemodialysis, otherwise healthy elderly, young people, and athletes do not experience kidney damage either. Moreover, numerous scientific reviews on both the long- and short-term safety of supplemental creatine have consistently found no adverse effects on kidney function in a wide range of doses. However, while doses >10 g/day have been found not to impair kidney function, there are fewer long-term trials using such high chronic daily intakes.
More recent studies on the regulation of CrT creatine transport activity have identified the protein kinase (Janus-Activating Kinase 2) JAK2, which suppresses the rate of creatine uptake via CrT without affecting creatine binding. JAK2 is a regulatory protein involved in stabilizing the cellular membrane and controlling water concentrations in response to osmotic stress. Similar to c-Src (a positive creatine transport regulator), Jak2 can also be activated by growth hormone signaling. The growth hormone receptor seems to activate these two factors independently, as gh-mediated activation of c-Src does not require JAK2. Given that c-Src is a positive regulator of CrT, JAK2 is a negative regulator, and the fact that downstream signals from both are induced by growth hormone, it is tempting to speculate that JAK2 activation downstream of the gh receptor may function as a homeostatic response to limit c-src induced creatine uptake. This has not been studied, however, and the effects of gh-induced JAK2 signaling on CrT activity have not been examined.
Heath suggests incorporating dropsets into your training routine by immediately decreasing the weight and repping out again to failure. “Dropsets overload the muscle with shorter rest periods and increasing volume which you need to grow,” says Heath. “That overload improves your body’s abilities to utilize more nutrients, natural growth hormone, and natural testosterone into those areas and makes the supplements you take more effective.” Heath’s favorite way to do dropsets is on a pin-loaded machine since it’s faster to switch weights.
Contrast loading is the alternation of heavy and light loads. Considered as sets, the heavy load is performed at about 85-95% 1 repetition max; the light load should be considerably lighter at about 30-60% 1RM. Both sets should be performed fast with the lighter set being performed as fast as possible. The joints should not be locked as this inhibits muscle fibre recruitment and reduces the speed at which the exercise can be performed. The lighter set may be a loaded plyometric exercise such as loaded squat jumps or jumps with a trap bar.
In elite swimmers, the growth hormone response to sprints appears to be attenuated (39%) following creatine loading, although after a 3g maintenance phase (22-27 weeks), this attenuation was reduced to less than 5%. Elsewhere in swimmers, resting growth hormone was unaffected by the loading phase, suggesting that this is an exercise-exclusive effect.
When endothelial cells have a higher creatine concentration, they appear to be mildly less permeable when incubated with 0.5-5mM creatine, while the higher concentration (5mM) is able to fully ablate TNF-α-induced neutrophil adhesion and both E-selectin and ICAM-1 expression. This effect was prevented with ZM241385, an A2A (adenosine) receptor antagonist, and since adenosine released by this receptor is known to be protective of endothelial cells, it is thought that creatine works vicariously through this receptor and adenosine release, thought to be due to releasing ATP (occurs in response to stress) which protects the cell via the A2A signaling system.
The creatine kinase system appears to be detectable in endothelial cells. Under basal conditions, creatine itself is expressed at around 2.85+/-0.62μM (three-fold higher than HUVEC cells). When incubating the medium with 0.5mM creatine, endothelial cells can take up creatine via the creatine transporter (SLC6A8) and increase both creatine (almost doubling) and phosphocreatine (nearly 2.5-fold) concentrations.
A 2011 survey of 33 supplements commercially available in Italy found that over 50% of them exceeded the European Food Safety Authority recommendations in at least one contaminant. The most prevalent of these contaminants was creatinine, a breakdown product of creatine also produced by the body. Creatinine was present in higher concentrations than the European Food Safety Authority recommendations in 44% of the samples. About 15% of the samples had detectable levels of dihydro-1,3,5-triazine or a high dicyandiamide concentration. Heavy metals contamination was not found to be a concern, with only minor levels of mercury being detectable. Two studies reviewed in 2007 found no impurities.
In recent years, the related areas of fitness and figure competition have increased in popularity, surpassing that of female bodybuilding, and have provided an alternative for women who choose not to develop the level of muscularity necessary for bodybuilding. McLish would closely resemble what is thought of today as a fitness and figure competitor, instead of what is now considered a female bodybuilder. Fitness competitions also have a gymnastic element to them. A study by the Clinical Journal of Sport Medicine found that female bodybuilders who are taking anabolic steroids are more likely to have qualified for substance dependence disorder, to have been diagnosed with a psychiatric illness, or to have a history of sexual abuse.
Despite all the awesomeness of hypertrophy, athletes may be more interested in effects on power. Power is the ability to generate high amounts of force in relatively short periods of time — more power means you can pull more weight in low-rep sets — and independent of the hypertrophy, just five to ten grams of creatine per day appears to improve power output by 12 to 26 percent.
The US FDA reports 50,000 health problems a year due to dietary supplements  and these often involve bodybuilding supplements. For example, the "natural" best-seller Craze, 2012's "New Supplement of the Year" by bodybuilding.com, widely sold in stores such as Walmart and Amazon, was found to contain N,alpha-Diethylphenylethylamine, a methamphetamine analog. Other products by Matt Cahill have contained dangerous substances causing blindness or liver damage, and experts say that Cahill is emblematic for the whole industry.
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.