It raised the question about performance-enhancing drugs. Their murky role in bodybuilding has long shrouded the sport. A 2013 documentary on Heath and Mr. Olympia called “Generation Iron” (a sort of bookend piece to 1977’s “Pumping Iron,” which launched Schwarzenegger and others to fame) called the topic “taboo.” It then insinuated that, of course, bodybuilders competing in top-level contests like Mr. Olympia use steroids.
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.
The majority of studies focusing on creatine supplementation report an increase in the body’s’ creatine pool [15-17]. There is a positive relationship between muscle creatine uptake and exercise performance . Volek et al  observed a significant increase in strength performance after 12 weeks creatine supplementation with a concurrent periodized heavy resistance training protocol. The creatine supplementation protocol consisted of a weeklong loading period of 25 g/d followed by a 5 g maintenance dose for the remainder of the training. These positive effects were attributed to an increased total creatine pool resulting in more rapid adenosine triphosphate (ATP) regeneration between resistance training sets allowing athletes to maintain a higher training intensity and improve the quality of the workouts along the entire training period.
A meta-analysis of 16 studies conducted on creatine and its influence on power and strength, (with or without exercise in all age groups above 16, but placebo controlled and without crossover) compiled studies utilizing a 5-7 day loading period with continued maintenance thereafter and studies assessing 1-3 rep bench press strength in trained young men. Seven studies (four of which are online) totaling 70 people using creatine and 73 people in placebo showed a 6.85kg increase in strength relative to placebo, the benefits of which peaked at 8 weeks. This meta-analysis also quantified a significant increase in squat strength (9.76kg) yet failed to find a significant influence on peak bicep contraction power, which may have been influenced by the two null studies being in elderly people while the positive study was statistically outweighed, but noted an 1.8-fold increase in power associated with creatine over placebo. The other meta-analysis conducted the following year calculated effect sizes for creatine supplementation and noted no significant differences between genders or when comparing trained and untrained individuals. The mean effect size of exercises lasting below 30s (those that use the creatine-phosphate system) was 0.24+/-0.02 and performed significantly better than placebo, where exercise increased performance by 4.2+/-0.6% while the addition of creatine enhanced this effect to 7.5+/-0.7%.
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.
One supplement, which a large body of research has proven effective in building muscle mass when combined with intensive strength training, is creatine (sold as creatine monohydrate). Creatine, a source of rapid energy, is stored in the muscles in small amounts. With creatine loading or supplementation, bodybuilders increase muscle stores of the energy-containing compound which then can be used to provide an extra boost for an intense-high-weight lifting session. Studies support that ingestion of a relatively high dose of creatine (20 to 30 grams per day for up to two weeks) increases muscle creatine stores by 10 to 30 percent and can boost muscle strength by about 10 percent when compared with resistance training alone (Rawson & Volek, 2003). Some athletes report (though research does not necessarily support) muscle cramping in response after using creatine supplements.
How much weight? Start with a pair of light dumbbell hand weights (2 to 3 pounds for women and 5 to 8 pounds for men). If you can’t do 12 repetitions (or reps are the number of times you do the exercise) the weight is too heavy. If your muscles don’t feel tired after 12 reps, it’s too light. Adjustable weights that can be strapped to wrists or ankles may be convenient if you have arthritis in your hands. You can also use home or gym weight machines, or resistance bands.
“There is a lot of mixed research on creatine’s ability to improve muscle strength,” the government website says. “However, analyses of this research show that creatine seems to modestly improve upper body strength and lower body strength in both younger and older adults.” Creatine has also been shown to improve athletes’ performance in rowing, soccer, and jumping height.
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.