Creatine is stored in the body in the form of creatine and as creatine phosphate, otherwise known as phosphocreatine, which is the creatine molecule bound to a phosphate group.[39] Creatine phosphate is thought to maintain the ATP/ADP ratio by acting as a high-energy phosphate reservoir.[40] The more ATP a muscle has relative to ADP, the higher its contractility is, and thus its potential strength output in vivo.[41][42] This pro-energetic mechanism also affects nearly all body systems, not just skeletal muscle. [39] During periods of rest and anabolism, creatine can gain a phosphate group through the creatine-kinase enzyme pathway, up to a cellular concentration of 30uM[24] to be later used for quick ATP resupply, when needed.[43][44] 
If you stop getting the results you want after several weeks of working out, it's time to mix things up. You need to challenge or "confuse" your muscles often to keep them growing. You can do this by putting a twist on your basic moves. Do a biceps curl with a reverse grip, for example. Or find a bench for the step-up move shown here. Change up your workout at least every 4 to 6 weeks for the best results.
When endothelial cells have a higher creatine concentration, they appear to be mildly less permeable when incubated with 0.5-5mM creatine, while the higher concentration (5mM) is able to fully ablate TNF-α-induced neutrophil adhesion and both E-selectin and ICAM-1 expression.[316] This effect was prevented with ZM241385, an A2A (adenosine) receptor antagonist,[316] and since adenosine released by this receptor is known to be protective of endothelial cells,[317][318] it is thought that creatine works vicariously through this receptor and adenosine release, thought to be due to releasing ATP (occurs in response to stress[319][320]) which protects the cell via the A2A signaling system.[316]
Contrary to certain rumors that animal-based protein is more suitable to trigger muscle growth than plant-based protein, a study by Mangano et al. (2017) could not provide any evidence for this. In contrast, if combined properly, plant-based protein can even have a higher biological quality. A combination of one part wheat protein (e.g. seitan) and two parts soy protein (e.g. tofu) has thus been favored by many bodybuilders. Some bodybuilders, such as Patrik Baboumian and Robert Cheeke, follow a strict vegan diet.[37]
What kind of exercises? Work all major muscle groups, starting with the larger muscles. Always include exercises for opposing muscles: for example, work the biceps and triceps of your arms, and the quadriceps and hamstrings of your thighs. Avoid above-the-shoulder exercises if you have arthritis in your upper body, and talk to your doctor before using leg press machines if you have arthritis in your knees or hips.
We hear this from 30 year olds and 60 year olds alike…and, like “I don’t have time,” it is a big fat lie! Even for the frail elderly, studies have shown that drastic results are possible in just 10 weeks of weightlifting (for both men and women in their 70s through their 90s). In fact, weight training has also been shown to delay Alzheimer’s and stave off dementia. So, if you think you might be “too old,” you’re probably the exact type of person that SHOULD be strength training!
Injections of creatine are known to be neuroprotective against low oxygen levels (hypoxia) even to neonatal rats.[532] This is thought to be associated with the increased collective pool of phosphocreatine and creatine.[236] Since oral ingestion of creatine by the mother increases brain concentrations of creatine by 3.6% in the fetus prior to birth,[531] it is thought to be protective in the fetuses subject to hypoxic (low oxygen) stressors, such as a caesarean section.

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]