Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. The intent is to increase muscle, increase body weight, improve athletic performance, and for some sports, to simultaneously decrease percent body fat so as to create better muscle definition. Among the most widely used are high protein drinks, branched-chain amino acids (BCAA), glutamine, arginine, essential fatty acids, creatine, HMB,[1] and weight loss products.[2] Supplements are sold either as single ingredient preparations or in the form of "stacks" – proprietary blends of various supplements marketed as offering synergistic advantages. While many bodybuilding supplements are also consumed by the general public the frequency of use will differ when used specifically by bodybuilders. One meta-analysis concluded that for athletes participating in resistance exercise training and consuming protein supplements for an average of 13 weeks, total protein intake up to 1.6 g/kg of body weight per day would result in an increase in strength and fat-free mass, i.e. muscle, but that higher intakes would not further contribute.[3] The muscle mass increase was statistically significant but modest - averaging 0.3 kg for all trials and 1.0–2.0 kg, for protein intake ≥1.6 g/kg/day.[3]
Taking high doses of creatine might harm the kidneys. Some medications can also harm the kidneys. Taking creatine with medications that can harm the kidneys might increase the chance of kidney damage.

Some of these medications that can harm the kidneys include cyclosporine (Neoral, Sandimmune); aminoglycosides including amikacin (Amikin), gentamicin (Garamycin, Gentak, others), and tobramycin (Nebcin, others); nonsteroidal anti-inflammatory drugs (NSAIDs) including ibuprofen (Advil, Motrin, Nuprin, others), indomethacin (Indocin), naproxen (Aleve, Anaprox, Naprelan, Naprosyn), piroxicam (Feldene); and numerous others.

This is why I never understand why girls who don’t want to “get bulky” are told by trainers to do 3 sets of 10-12 (or 5 sets of 1,000 reps of bicep curls with a 1 lb pink dumbbell). While it’s difficult for women to gain any sort of size lifting in ANY rep range, if we were trying to gain muscle size, that’s EXACTLY what we would want to do (as it would be causing sarcoplasmic hypertrophy).
There are countless reasons to lift weights and build strong muscles, including injury prevention, improved bone density, and a lower risk for type 2 diabetes and other diseases—not to forget that bad-ass feeling you get when you can haul a giant piece of furniture up the stairs all by yourself. Another often-cited benefit to strength training is that it will increase your metabolism. But how much does your metabolism increase with strength training? The answer depends on many different factors.
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]