Don’t take sets to the point of failure—where you absolutely can’t perform another rep. You should never get to where you’re turning purple and screaming like you’re getting interviewed by “Mean” Gene Okerlund before WrestleMania. Most of the time, you want to end your sets two reps before total failure. Not sure when that is? The moment your form breaks down, or you’re pretty sure it’s going to break down, end the set.
The basic principles of weight training are essentially identical to those of strength training, and involve a manipulation of the number of repetitions (reps), sets, tempo, exercise types, and weight moved to cause desired increases in strength, endurance, and size. The specific combinations of reps, sets, exercises, and weights depends on the aims of the individual performing the exercise.
In competitive bodybuilding, bodybuilders aspire to develop and maintain an aesthetically pleasing body and balanced physique.[16][17] In prejudging, competitors do a series of mandatory poses: the front lat spread, rear lat spread, front double biceps, back double biceps, side chest, side triceps, Most Muscular (men only), abdominals and thighs. Each competitor also performs a personal choregraphed routine to display their physique. A posedown is usually held at the end of a posing round, while judges are finishing their scoring. Bodybuilders usually spend a lot of time practising their posing in front of mirrors or under the guidance of their coach.
Supplementation of creatine at 5g daily alongside rehabilitation (after limb immobilization for two weeks while taking 20g daily) is associated with a preservation in GLUT4 levels, which were reduced during immobilization. During exercise rehabilitation, it increased to 40% above placebo.[330] This study failed to note an increase in GLUT4 in control, despite exercise normally doing so.[331][332] This effect is thought to be the result of the low frequency of activity. Thus, creatine was thought to augment the increase (insignificant due to low exercise) to significant levels.[330] In other studies, creatine was found to increase GLUT by approximately 30% relative to control, but this effect failed to reach statistical significance. This study did not issue an exercise protocol.[207]
At the end of the day, you have to focus on how you feel. “Listen to your body,” says Davis. “It tells you when it needs a day off.” As a rule of thumb, take a rest day if your perceived pain is above a seven on a scale of 10, Davis advises. Or, focus on a different body part (say, if your legs are sore, focus on upper-body moves). Can't stop, won't stop—at least, till your next rest day.
It was later noted that creatine was able to nonsignificantly augment various proinflammatory cytokines (CCL2, iNOS, ICAM-1, TGF-β, TIMP-1) and the presence of eosinophils in lung tissue, as well as to per se cause lung infiltration of these immune cells without requiring the presence of the allergen.[442] Neutrophils and macrophages were unaffected,[442] reflecting the past study of no influence on macrophages,[440] but the only instance where creatine appeared to either significantly add to ovalbumin or to per se induce statistically significant increases were in IL-5 secretion and goblet cell infiltration, although VCAM-1 expression was close. While creatine per se increased nF-κB activity, it suppressed the ovalbumin-induced increase.[442]
However, if you increase the demands you are placing on your body by increasing the weight being lifted, lifting the same weight for additional reps, or just doing something that increases the demands that your body needs to meet, then your body will have no other choice but to make the changes and improvements necessary for it to adapt to this environment and remain capable of performing these tasks.

Although it does not appear to influence baseline antioxidant enzymes (measured in red blood cells), one week of creatine loading in otherwise healthy young adults has increased red blood cell (RBC) content of the superoxide dismutase (SOD) enzyme in response to a sprint test by 8.1% immediately after exercise. This was no longer detectable after an hour since placebo increased to match.[299] Glutathione and catalase are unaffected.[299]

However, in the beginning weeks of starting a new workout routine, the majority of strength gains aren't actually a result of this muscle protein synthesis and hypertrophy. Rather, they are a result of the body's neurological system learning when and how to fire the needed muscle cells, explains Abbie E. Smith-Ryan, associate professor of exercise physiology at the department of exercise and sport science at the University of North Carolina–Chapel Hill. Think of it this way: The first time you perform a new exercise, say a bench press, you likely feel pretty shaky. Your arms aren't totally in sync and the weights may sway a bit from side to side. But by the time you perform your second or third set of that same exercise, the practice gets a little smoother. That's your neurological system at work.
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.[192] In contrast, the creatine precursor (guanidinoacetate, or GAA) only appears to enter this transporter during creatine deficiency.[192] 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[192] is the major source of neural creatine.[193][192] However, “capable of passage” differs from “unregulated passage” and creatine appears to have tightly regulated entry into the brain in vivo[193]. 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.[193] These kinetics may be a reason for the relative lack of neural effects of creatine supplementation in creatine sufficient populations.