You've figured out the exercises you should be doing, but what about the number of sets and repetitions? Your decision should be based on your goals. The American College of Sports Medicine recommends 8-12 reps for muscular strength and 10-15 reps for muscular endurance. They also recommend at least 1 set of each exercise to fatigue although you'll find that most people perform about 2-3 sets of each exercise. In general:
Extracellular creatine (creatine outside of a cell) appears to influence creatine uptake into a cell. It seems that prolonged and excessive levels of creatine actually suppress uptake (a form of negative regulation to prevent excessive influx). In vitro studies in rat muscle cells have shown that including 1mM creatine into cell culture medium substantially reduces creatine uptake into cells. The inhibitory effect was partially negated by protein synthesis inhibitors, suggesting that high levels of creatine induce the expression of a protein that suppresses creatine transporter activity. Similar findings were reported in a later study in cultured mouse myoblasts, which noted a 2.4-fold increase in intracellular creatine levels in the presence of the protein synthesis inhibitor cyclohexamide.
The concentration in healthy controls (57+/-8 years) without supplementation of creatine appears to be around 1.24+/-0.26µM per gram of hemoglobin and appears to decrease in concentration during the aging process of the erythrocyte. Otherwise healthy subjects who take a loading phase of creatine (5g four times daily for five days) can experience a 129.6% increase in erythrocytic creatine concentrations from an average value of 418µM (per liter) up to 961µM with a large range (increases in the range of 144.4-1004.8µM), and this effect appears to correlate somewhat with muscular creatine stores.
It has also been noted that supplementing creatine (which reduces internal synthesis of creatine and methylation requirements) preserved folate and tetrahydrofolate status (42% and 23%), which acted to preserve methyl groups for other processes. Despite this effect, global DNA methylation decreases by 22% (assessed by the 5-methylcytosine/cytosine ratio) following creatine supplementation, which is usually seen as an anti-cancer effect in developed mammals. This study was unable to demonstrate why this reduction occured and opposing effects have been noted in females with Rett syndrome supplementing 200mg/kg creatine for 1 year, during which global methylation increased, secondary to preserving other methyl donors.
Bodybuilders may supplement their diets with protein for reasons of convenience, lower cost (relative to meat and fish products), ease of preparation, and to avoid the concurrent consumption of carbohydrates and fats. Additionally, some argue that bodybuilders, by virtue of their unique training and goals, require higher-than-average quantities of protein to support maximal muscle growth. However, there is no scientific consensus for bodybuilders to consume more protein than the recommended dietary allowance. Protein supplements are sold in ready-to-drink shakes, bars, meal replacement products (see below), bites, oats, gels and powders. Protein powders are the most popular and may have flavoring added for palatability. The powder is usually mixed with water, milk or fruit juice and is generally consumed immediately before and after exercising or in place of a meal. The sources of protein are as follows and differ in protein quality depending on their amino acid profile and digestibility:
Escolar, D. M., Buyse, G., Henricson, E., Leshner, R., Florence, J., Mayhew, J., Tesi-Rocha, C., Gorni, K., Pasquali, L., Patel, K. M., McCarter, R., Huang, J., Mayhew, T., Bertorini, T., Carlo, J., Connolly, A. M., Clemens, P. R., Goemans, N., Iannaccone, S. T., Igarashi, M., Nevo, Y., Pestronk, A., Subramony, S. H., Vedanarayanan, V. V., and Wessel, H. CINRG randomized controlled trial of creatine and glutamine in Duchenne muscular dystrophy. Ann Neurol 2005;58(1):151-155. View abstract.
It is regularly reported that creatine supplementation, when combined with heavy resistance training leads to enhanced physical performance, fat free mass, and muscle morphology [18-22]. A 2003 meta analysis  showed individuals ingesting creatine, combined with resistance training, obtain on average +8% and +14% more performance on maximum (1RM) or endurance strength (maximal repetitions at a given percent of 1RM) respectively than the placebo groups. However, contradicting studies have reported no effects of creatine supplementation on strength performance. Jakobi et al  found no effects of a short term creatine loading protocol upon isometric elbow flexion force, muscle activation, and recovery process. However, this study did not clearly state if creatine supplementation was administered concurrent with resistance training. Bemben et al  have shown no additional benefits of creatine alone or combined with whey protein for improving strength and muscle mass after a progressive 14 weeks (3 days per week) resistance training program in older men. These conflicting results can be explained by the possibility that the supplemented groups were formed by a greater amount of non-responders or even because creatine supplementation was administered on the training days only (3 times a week). This strategy has not been adequately tested as effective in middle aged and older men for maintaining post loading elevated creatine stores .
If you're looking to add muscle mass to your frame, hitting the weights hard is a given. Quality time in the gym begins a cascade of changes that will stimulate your muscles to grow bigger in response to the challenges you throw their way. It's tempting to think that's all it takes to add muscle to your body. After all, you can actually feel your biceps growing after an intense set of curls.
After your standard whey protein powder, creatine may be the most popular sports supplement on Earth, and with good reason. A lot of supplements out there have a few promising studies suggesting they may improve some aspect of performance. Creatine has hundreds of them, and study after study has shown that among most people (a small percentage of are non-responders) it can have a significant effect on several areas of performance.
Our bodies store creatine in our muscles so that we have quick access to it for fast, high-intensity movements, like sprinting or powerlifting, explains Autumn Bates, a certified clinical nutritionist and sports nutritionist in private practice in Manhattan Beach, California. “It's a nonessential amino acid, meaning your body creates it and you don't need to primarily get it from food.”
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.
There you have it — our five favorite creatine products on the market. But when you’ve tried as many creatines as we have, there were a lot of others that we loved but didn’t make the very top of our list for the previous categories. That’s why we’ve also come up with a list of the best creatines for men, best creatines for women, best creatines for muscle growth, for bulking, for the brain, and the best micronized creatine. Keep reading for our favorite picks!
It’s true—your genes can play a role when it comes to building muscle. In general, there are two types of muscle fibers: Type I, which are slow twitch, and Type II, which are fast twitch. Depending on which you have more of, you may have an easier or harder time gaining muscle. “Fast twitch muscle fibers are two times as thick as slow twitch muscle fibers, lending to the overall thickness of the muscle without any activity,” explains Lovitt. “Those people with a genetic predisposition of a high percentage of these fibers can increase muscle size very easily while the people with a higher percentage of slow twitch muscle fibers have to work really hard to put on mass.” It’s the reason why a world-class sprinter genetically has more fast twitch muscle fibers than a world-class marathoner—it comes down to what we’re born with.
Creatine supplementation appears to be somewhat similar to TMG supplementation in the sense that they both promote localized synthesis of phosphatidylcholine, effluxing triglycerides from the liver into serum and thus potently protecting from diet-induced fatty liver. The concentration at which this occurs is within the range supplemented by humans.
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.