Even human studies can be misinterpreted or manipulated. A few years ago a then-esoteric trace mineral called boron was found to increase testosterone, but only in older women, as it turned out. When boron was tested in young men engaged in weight training, it proved worthless for increasing testosterone. That doesn't mean boron is useless; it helps the body use the minerals calcium and magnesium, and it appears to increase mental alertness.
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.
Incubation of a β-cell with additional creatine (5-10mM), even at saturated concentrations of glucose, is able to further increase insulin secretion in response to glucose, specifically as the leucine metabolite 2-ketoisocaproic acid, potassium, and a potassium channel blocker were all ineffective.[494] This has been found to occur in rats given 2% of the diet as creatine[345] but has since failed in humans given 5g of creatine.[351]
On the other hand, the gluteus maximus (and other muscles of the glutes) can also become weak and unstable when someone doesn’t get enough physical activity, for example if they sit for many hours per day at a desk and live a mostly sedentary lifestyle. Some experts call this phenomenon “gluteal amnesia,” which occurs when the muscles near the buttocks become overstretched and underused, resulting in weakness and stiffness. Some common aches, pains and injuries tied to weak gluteus maximus muscles can include:
Creatine levels in the blood tend to return to baseline (after a loading with or without the maintenance phase) after 28 days without creatine supplementation.[152][200][201] This number may vary slightly from one individual to another, and for some may exceed 30 days.[202] Assuming an elimination rate of creatinine (creatine’s metabolite) at 14.6mmol per day,[35][201] six weeks of cessation is approaching the upper limit for serum creatine to completely return to baseline.

^ David KG, Dingemanse E, Freud JL (May 1935). "Über krystallinisches mannliches Hormon aus Hoden (Testosteron) wirksamer als aus harn oder aus Cholesterin bereitetes Androsteron" [On crystalline male hormone from testicles (testosterone) effective as from urine or from cholesterol]. Hoppe-Seyler's Z Physiol Chem (in German). 233 (5–6): 281–83. doi:10.1515/bchm2.1935.233.5-6.281.

ZMA: This supplement is a combination of zinc, magnesium and vitamin B-6. Some research shows that this combination can help raise testosterone levels. In the trial, subjects took a daily dose of ZMA (which included 30 mg zinc monomethionine, 450 mg magnesium aspartate and 10.5 mg vitamin B-6) at night during 7 weeks. Other hormones like IGF also increased, while the stress hormone, cortisol was reduced, creating an overall more favorable hormone profile. Not surprisingly, muscle performance also improved. (n) This paper is surrounding in controversy, however, because one of the scientists involved also holds the trademark for ZMA, and the research is company-funded.
^ "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.
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.
At the end of the day, yes, strength training does impact your metabolism, but any boost you get will be minimal and completely secondary to all of the other health benefits of strength training. Any change in metabolism or increase in calorie burn will vary widely from person to person, and depends on so many factors: your genetics, eating habits, health conditions, what workout you do that day, how much sleep you’re getting, and even how stressed you are on any given day. But incorporating a couple of strength training sessions into your fitness routine is worth doing no matter what—you’ll feel yourself get stronger, and put yourself in a position to say healthier throughout life. Those are the best, most promising benefits to work for.
The effect excess testosterone has on the body depends on both age and sex. It is unlikely that adult men will develop a disorder in which they produce too much testosterone and it is often difficult to spot that an adult male has too much testosterone. More obviously, young children with too much testosterone may enter a false growth spurt and show signs of early puberty and young girls may experience abnormal changes to their genitalia. In both males and females, too much testosterone can lead to precocious puberty and result in infertility. 

Every gym has a guy shaped like a lightbulb. He's the one who neglects his lower body. If you don't want to be that guy, work your major leg muscles on the leg press machine. Place your feet on the plate with knees bent at 90 degrees. Grasp the handles and slowly push the plate out until your knees are straight but not locked. Pause and slowly return to the starting spot.
Incubation of a β-cell with additional creatine (5-10mM), even at saturated concentrations of glucose, is able to further increase insulin secretion in response to glucose, specifically as the leucine metabolite 2-ketoisocaproic acid, potassium, and a potassium channel blocker were all ineffective.[494] This has been found to occur in rats given 2% of the diet as creatine[345] but has since failed in humans given 5g of creatine.[351]
Taking creatine supplements may increase the amount of creatine in the muscles. Muscles may be able to generate more energy or generate energy at a faster rate. Some people think that taking creatine supplements along with training will improve performance by providing quick bursts of intense energy for activities such as sprinting and weightlifting.
In otherwise healthy adults subject to leg immobilization for two weeks while taking 20g creatine daily during immobilization and then 5g daily during eight weeks of rehabilitation, it was noted that the creatine group failed to reduce atrophy during the immobilization (10% reduction in cross sectional area and 22-25% reduction in force output) despite preventing a decrease in phosphocreatine, yet experienced a significantly enhanced rate of regrowth and power recovery.[358] A similarly structured and dosed study has also noted greater expression of skeletal muscle, GLUT4 expression, and a 12% increase in muscle phosphocreatine content.[330]

Testosterone fluctuates according to age and life circumstance, often plummeting at the onset of parenthood, and spiking (for some) during moments of triumph. Romantic relationships, too, can impact a person’s testosterone production; though the reasons are still not fully understood, entering a relationship tends to increase women’s testosterone levels, while decreasing men’s. Since males produce significantly more testosterone than females—about 20 times more each day—females can be more sensitive to these fluctuations. High levels of testosterone, particularly in men, have been correlated with a greater likelihood of getting divorced or engaging in extramarital affairs, though a causal link has not been established.

Kornblum, C., Schroder, R., Muller, K., Vorgerd, M., Eggers, J., Bogdanow, M., Papassotiropoulos, A., Fabian, K., Klockgether, T., and Zange, J. Creatine has no beneficial effect on skeletal muscle energy metabolism in patients with single mitochondrial DNA deletions: a placebo-controlled, double-blind 31P-MRS crossover study. Eur J Neurol 2005;12(4):300-309. View abstract.
Tribulus Terrestris: A fruit from the Mediterranean, this supplement has been used in the Indian traditional medicine of Ayurveda. In addition to helping increase testosterone, many people take it to increase libido and as a cardioprotective aid. (10) Unfortunately, despite the fact that there are claims that tribulus terrestris can increase testosterone levels, studies don’t back up these claims.  There is some evidence, however, that it may improve athletic performance. If you want to choose one of the supplements for men, this should be your pick.
If you're a serious strength or physique athlete, you've surely heard that supplements can help you get the most from your intense training sessions and on-point diet. But which supplements? The market is overstuffed like a bodybuilder in a child's blazer! You might be tempted to wander through a digital forest of get-big blogs and personal guru websites, but unfortunately those places can often be rife with misinformation.
Focus on form. Good form means you can reap all of the benefits of your workout and avoid injuries at the same time. To maintain proper form, pay attention to your posture (stand tall with chest lifted and abs held tight), move slowly (this ensures you're relying on muscles, not momentum, to do the lifting), and remember to breathe. Many people hold their breath while exerting, but exhaling during the hardest part of the exercise helps fuel the movement.