Macrophages are known to express creatine kinase[290] and take creatine up from a medium through a sodium dependent mechanism (likely the creatine transporter) in a saturable manner,[435] with a second component that requires there to be no concentration gradient to work against (likely passive diffusion) but this effect tends to only account for up to 10% of total uptake in the physiological range (20-60µM).[435] Supraphysiological range was not tested.
A: At the end of the day, the most important variable regarding weight gain or loss is calorie consumption. However, meal frequency and timing around activity can both influence workout intensity and duration thus potentially allowing for further improvements in body composition. Remember, muscle growth isn’t a pulsatile process, it doesn’t just acutely spike and then return to baseline so if there aren’t circulating amino acids within the blood stream then they’ll have to be broken down from muscle as this is the highest form of concentrated amino acids within the body. That being said, it would probably be a good idea to consume anywhere from 3-6 meals spread throughout the day depending upon your schedule and preference. Ideally, we want to stimulate anabolism through food every 3-5 hours.

"Eating well" is tough to objectively quantify. One can eat "well" but that doesn't necessarily mean that you are eating enough to build muscle or recover adequately from workouts. Also, taking protein shakes doesn't guarantee that one will start to accrue massive slabs of lean body mass. Muscle anabolism is a fairly complex metabolic process which has a number of contributing factors at the cellular level and can't be reduced to a single supplement or dietary component.
Weight training aims to build muscle by prompting two different types of hypertrophy: sarcoplasmic and myofibrillar. Sarcoplasmic hypertrophy leads to larger muscles and so is favored by bodybuilders more than myofibrillar hypertrophy, which builds athletic strength. Sarcoplasmic hypertrophy is triggered by increasing repetitions, whereas myofibrillar hypertrophy is triggered by lifting heavier weight.[23] In either case, there is an increase in both size and strength of the muscles (compared to what happens if that same individual does not lift weights at all), however, the emphasis is different.
^ Jump up to: a b c d e f g h Momaya A, Fawal M, Estes R (April 2015). "Performance-enhancing substances in sports: a review of the literature". Sports Med. 45 (4): 517–531. doi:10.1007/s40279-015-0308-9. PMID 25663250. Wilson et al. [91] demonstrated that when non-resistance trained males received HMB pre-exercise, the rise of lactate dehydrogenase (LDH) levels reduced, and HMB tended to decrease soreness. Knitter et al. [92] showed a decrease in LDH and creatine phosphokinase (CPK), a byproduct of muscle breakdown, by HMB after a prolonged run. ... The utility of HMB does seem to be affected by timing of intake prior to workouts and dosage [97]. 

Gordon, P. H., Cheung, Y. K., Levin, B., Andrews, H., Doorish, C., Macarthur, R. B., Montes, J., Bednarz, K., Florence, J., Rowin, J., Boylan, K., Mozaffar, T., Tandan, R., Mitsumoto, H., Kelvin, E. A., Chapin, J., Bedlack, R., Rivner, M., McCluskey, L. F., Pestronk, A., Graves, M., Sorenson, E. J., Barohn, R. J., Belsh, J. M., Lou, J. S., Levine, T., Saperstein, D., Miller, R. G., and Scelsa, S. N. A novel, efficient, randomized selection trial comparing combinations of drug therapy for ALS. Amyotroph.Lateral.Scler. 2008;9:212-222. View abstract.
Using too much weight, too soon; always start lower than your expected ability and work your way up that first workout. If your form suffers, you are swinging the weight, or using momentum, this indicates you may be using too much weight. Greater momentum increases the potential for injury and reduces the effectiveness to the muscle group being targeted. 

You are encouraged to confirm information obtained from or through this website with other sources. Our content is not a substitute for qualified medical advice. The supplement summaries on this website may not include all the information pertinent to your use. Before starting a diet, taking new supplements, or beginning an exercise program, check with your doctor to clear any lifestyle changes. Only your doctor can determine what is right for you based on your medical history and prescriptions.
Keep in mind that while creatine boosts your performance in the gym, helping you achieve better muscle building results, it is also associated with some side effects. One of the main concerns is that creatine may worsen or cause kidney problems. Creatine shouldn’t be taken in combination with diabetes medications, acetaminophen, diuretics or caffeine. As always, speak with your doctor before taking supplements to make sure that the product is safe for you (6). Generally, for most people, the supplement is considered to be among the safer weight lifting supplements.
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 [21]. 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 [22]. 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 [23].
Peirano, R. I., Achterberg, V., Dusing, H. J., Akhiani, M., Koop, U., Jaspers, S., Kruger, A., Schwengler, H., Hamann, T., Wenck, H., Stab, F., Gallinat, S., and Blatt, T. Dermal penetration of creatine from a face-care formulation containing creatine, guarana and glycerol is linked to effective antiwrinkle and antisagging efficacy in male subjects. J.Cosmet.Dermatol. 2011;10(4):273-281. View abstract.
It is known that intracellular energy depletion (assessed by a depletion of ATP) stimulates AMPK activity in order to normalize the AMP:ATP ratio,[333][334] and when activated AMPK (active in states of low cellular energy[335] and colocalizes with creatine kinase in muscle tissue[336]) appears to inhibit creatine kinase via phosphorylation (preserving phosphocreatine stores but attenuating the rate that creatine buffers ATP). While phosphocreatine technically inhibits AMPK, this does not occur in the presence of creatine at a 2:1 ratio.[334] It seems that if the ratio of phosphocreatine:creatine increases (indicative of excess cellular energy status) that AMPK activity is then attenuated, since when a cell is in a high energy status, there is less AMP to directly activate AMPK.[334][336][337]