The biggest mistake among young would-be bodybuilders is overdoing it, followed by not learning the proper techniques. Take those breaks and follow the correct form, or you'll give your body stress and injuries instead of muscle. Also make sure you're getting a large but balanced diet. Teens going through growth spurts need lots of food, especially when they're working out.
I know this goes against the recommendations you often see in stereotypical bodybuilding routines (i.e. the ones that involve having a single “chest day” or “arm day” or “shoulder day” once a week), but that’s just one of the many reasons why those types of routines suck for us natural, genetically-average people, and work best for steroid users with great genetics.
Electrolytes derive mainly from minerals in the diet and they maintain fluid balance and assist the nervous system to perform muscle contractions. Electrolytes are sodium, potassium, magnesium, calcium and chloride, bicarbonate, phosphate, sulfate. Exercisers are particularly dependent on sodium and potassium balance. Carbohydrates are important for fueling exercise, including vigorous weight training, and in post-exercise energy replacement nutrition. Carbohydrates, mostly sugars, are formulated in sports drinks with electrolytes such as sodium chloride and potassium and sometimes magnesium.
Another category of muscle-building supplements that lifters and bodybuilders use to improve their results are branched-chained amino acids (BCAAs), or BCAAs. Of the 20 amino acids that make up protein, just three are referred to as BCAAs: leucine, isoleucine, and valine. These are the specific amino acids that have been shown to stimulate protein synthesis and help regulate protein metabolism.
I know this goes against the recommendations you often see in stereotypical bodybuilding routines (i.e. the ones that involve having a single “chest day” or “arm day” or “shoulder day” once a week), but that’s just one of the many reasons why those types of routines suck for us natural, genetically-average people, and work best for steroid users with great genetics.
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.
One study in elite swimmers subject to sprints (varying in length from 25-100m) failed to find benefit with creatine supplementation, although there was also a failure on leg extension strength, suggesting nonresponse.[399] This has been noted twice elsewhere with a similar protocol,[400][401] while one study in elite swimmers subject to single 50m or 100m sprints found benefit with supplementation[402] and one found benefit with six repeated 50m sprints by 2%, yet not ten repeated 25m sprints with elite male swimmers (females failed to find benefit).[403] Another study also noted benefits in elite swimmers on a sprinting protocol.[156] Overall, the evidence is quite limited and suggests either a mild, or more likely, no increase for elite swimmers, although one study confirming an increase in body and water weight[401] failed to find a decrement in performance.
Muscle building supplements can serve as a great tool for helping you increase your muscle mass.  Always remember that, as when taking any supplement, it’s best to consult with your doctor to ensure that you won’t face any adverse interactions with medications or negatively affect your health. While the muscle building supplements listed are all generally safe, individuals with chronic health conditions should be especially careful.
^ "The History of Weightlifting". USA Weightlifting. United States Olympic Committee. Archived from the original on 7 July 2013. Retrieved 3 September 2018. The genealogy of lifting traces back to the beginning of recorded history where man's fascination with physical prowess can be found among numerous ancient writings. A 5,000-year-old Chinese text tells of prospective soldiers having to pass lifting tests.
Due to a combination of its neuroprotective effects and dopaminergic modulatory effects, creatine has been hypothesized in at least one review article to be of benefit to drug rehabilitation.[266] This study used parallels between drug abuse (usually methamphetamines) and traumatic brain injury[267][268] and made note of creatine being able to reduce symptoms of brain trauma, such as headaches, fatigue, and dizziness in clinical settings in two pilot studies.[269][270] No studies currently exist that examine creatine supplementation and drug rehabilitation.
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%),[312] 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.[461] This study was unable to demonstrate why this reduction occured[461] 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.[462]
Cyclocreatine appears to be passively diffused through membranes and not subject to the creatine transporter, which can be beneficial for cases where creatine transporter function is compromised (creatine non-response and SLG6A8 deficiency). Similar to other forms of creatine, it buffers ATP concentrations, although its efficacy as a supplement in otherwise healthy people is currently unknown.

Creatine supplementation may also be of benefit to injured athletes. Op’t Eijnde et al [39] noted that the expected decline in GLUT4 content after being observed during a immobilization period can be offset by a common loading creatine (20g/d) supplementation protocol. In addition, combining CM 15g/d for 3 weeks following 5 g/d for the following 7 weeks positively enhances GLUT4 content, glycogen, and total muscle creatine storage [39].
Mercimek-Mahmutoglu, S., Stoeckler-Ipsiroglu, S., Adami, A., Appleton, R., Araujo, H. C., Duran, M., Ensenauer, R., Fernandez-Alvarez, E., Garcia, P., Grolik, C., Item, C. B., Leuzzi, V., Marquardt, I., Muhl, A., Saelke-Kellermann, R. A., Salomons, G. S., Schulze, A., Surtees, R., van der Knaap, M. S., Vasconcelos, R., Verhoeven, N. M., Vilarinho, L., Wilichowski, E., and Jakobs, C. GAMT deficiency: features, treatment, and outcome in an inborn error of creatine synthesis. Neurology 8-8-2006;67:480-484. View abstract.

^ Haykowsky MJ, Liang Y, Pechter D, Jones LW, McAlister FA, Clark AM (June 2007). "A meta-analysis of the effect of exercise training on left ventricular remodeling in heart failure patients: the benefit depends on the type of training performed". Journal of the American College of Cardiology. 49 (24): 2329–36. doi:10.1016/j.jacc.2007.02.055. PMID 17572248.
There have been a few reported renal health disorders associated with creatine supplementation [73,74]. These are isolated reports in which recommended dosages are not followed or there is a history of previous health complaints, such as renal disease or those taking nephrotoxic medication aggravated by creatine supplementation [73]. Specific studies into creatine supplementation, renal function and/or safety conclude that although creatine does slightly raise creatinine levels there is no progressive effect to cause negative consequences to renal function and health in already healthy individuals when proper dosage recommendations are followed [73-77]. Urinary methylamine and formaldehyde have been shown to increase due to creatine supplementation of 20 g/d; this however did not bring the production outside of normal healthy range and did not impact on kidney function [56,78]. It has been advised that further research be carried out into the effects of creatine supplementation and health in the elderly and adolescent [73,75]. More recently, a randomized, double blind, 6 month resistance exercise and supplementation intervention [79] was performed on elderly men and women (age >65 years) in which subjects were assigned to either a supplement or placebo group. The supplement group was given 5 g CM, 2 g dextrose and 6 g conjugated linoleic acid/d, whilst the placebo group consumed 7 g dextrose and 6 g safflower oil/d. CM administration showed significantly greater effects to improve muscular endurance, isokinetic knee extension strength, fat free mass and to reduce fat mass compared to placebo. Furthermore the supplement group had an increase in serum creatinine but not creatinine clearance suggesting no negative effect on renal function.
When creatine is increased in the fetus (from maternal supplementation of 5% creatine), the fetus has a greater chance of survival and increased growth rates to a level not significantly different than vaginal birth.[531] Protection from hypoxia has also been noted in the offspring’s diaphragm (through preserved muscle fiber size),[533] kidneys,[534] and neural tissue (due to less oxidation in the brain and less cellular apoptosis).[535]
Rice Protein: An alternative protein powder for muscle gain, rice protein is ideal for people who are lactose intolerant or have a milk allergy. As far as muscle gain and body composition when taken post-workout, this study showed that there was zero difference in outcomes when comparing taking whey protein and rice protein. So, if you prefer using rice protein, you can take it with confidence knowing that you’ll be able to achieve the same results you’d achieve if you were taking whey protein.
Some people do have allergies to soy, or they have an intolerance to soy. If you notice certain symptoms (like a headache) after soy consumption, you may have an intolerance. Discovering your food intolerances/allergies would also be handled by a Dietitian. For the general population who are not allergic/intolerant to soy, however, soy-based products can be a part of a healthy diet. New research has shown that soy is not harmful as people fear. If soy gives you issues, you could always opt for whey protein, pea protein or other forms of vegetable protein. Have you seen our article on protein powders? Click here.
Finally, starvation (nutrient deprivation for four days) appears to increase activity of the creatine transporter secondary to decreasing serine phosphorylation (SGK target)[173] with no influence on tyrosine phosphorylation (c-Src target).[173] Starvation-induced increases in creatine influx do not necessarily mean more phosphocreatine, however, due to a depleted cellular energy state.[173]
Safety. Iron overload may cause a disease called hemochromatosis in some susceptible people. Iron supplements should only be prescribed by a doctor, and for athletes or those who train heavily, a sports physician combined with a sports dietitian may be preferable. Be sure to take care with this because iron supplements should not be taken casually. Iron supplements may cause constipation and gastric upset in some people.
Creatine is known to be present in the retina due to the expression of creatine kinase (CK)[466][39] and the GAMT enzyme of creatine synthesis, which is also present in the mammalian retina.[467] Creatine in the blood can be transported into the retina via the creatine transporter (confirmed in humans[468]), and inhibiting transporter activity (by depleting the medium of chloride and sodium) reduces uptake by 80%.[469] The fact that not all uptake was inhibited suggests that another transporter, such as the monocarboxylate transporter MCT12 (or SLC16A12),[470] plays a role, perhaps moreso in the lens, where its levels were comparable to that of the major creatine transporter SLC6A8.[470] 
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]