Creatine retention (assessed by urinary analysis) tends to be very high on the first loading dose (65±11%) and declines throughout the loading phase (23±27%). This is likely due to increased muscular uptake when creatine stores are relatively low, which has been noted in vegetarians. So, creatine absorption is very high initially, but decreases througout the loading phase, as muscle creatine stores increase.
Post workout, it’s important to restore your body’s energy by consuming protein and carbs. When you’re trying to build muscle, this is an especially important step. Protein powder is a great muscle builder for your post-workout routine, as long as you include a carbohydrate as well. You can get this by eating a banana or adding oats or banana to your protein shake. Or simply cook up a batch of healthy oatmeal muffins and include protein powder in your recipe. Then, enjoy your post-workout supplement as a delicious snack!
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.
In regard to bioenergetics, phosphorylated cyclocreatine appears to have less affinity for the creatine kinase enzyme than phosphorylated creatine in terms of donating the high energy phosphate group (about 160-fold less affinity) despite the process of receiving phosphorylation being similar. When fed to chickens, phosphorylated cyclocreatine can accumulate up to 60mM in skeletal muscle, which suggests a sequestering of phosphate groups before equilibrium is reached. Cyclocreatine still has the capacity to donate phosphate, however, as beta-adrenergic stimulated skeletal muscle (which depletes ATP and glycogen) exhibits an attenuation of glycogen depletion (indicative of preservation of ATP) with phosphocreatine.
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. This effect was prevented with ZM241385, an A2A (adenosine) receptor antagonist, and since adenosine released by this receptor is known to be protective of endothelial cells, 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) which protects the cell via the A2A signaling system.
Creatine is classified as a "dietary supplement" under the 1994 Dietary Supplement Health and Education Act and is available without a prescription. Creatine is not subjected to FDA testing, and the purity and hygienic condition of commercial creatine products may be questionable . A 1998 FDA report lists 32 adverse creatine-associated events that had been reported to FDA. These include seizure, vomiting, diarrhea, anxiety, myopathy, cardiac arrhythmia, deep vein thromboses and death. However, there is no certainty that a reported adverse event can be attributed to a particular product . A recent survey of 28 male baseball players and 24 male football players, ages 18 to 23, found that 16 (31%) experienced diarrhea, 13 (25%) experienced muscle cramps, 7 (13%) reported unwanted weight gain, 7 (13%) reported dehydration, and 12 reported various other adverse effects .
The first published results (not blinded) noted that a loading phase of 20g of creatine for a week, followed by 3g daily for up to six months, was able to enhance maximal voluntary isometric muscular contraction (MVIC) on a dynamometer for both the knee and elbow joints, with enhanced fatigue resistance on the same joints in more than half of subjects (53-70% response rate).
When it comes to building muscle, there are numerous theories, methods, and preferences. Whether the goal is improved health, aesthetics, performance, or a combination of all three, there is no shortage of advice to help you get there. So much so that it can sometimes become overly complicated and you forget about the basic facts. But, it’s simpler than it seems.
The pancreas is one of the extrahepatic (beyond the liver) organs that can synthesize creatine, alongside the kidneys. Freshly prepared pancreatic β-cells will normally secrete insulin in response to glucose stimulation, and it appears that phosphocreatine is required for this effect, since phosphocreatine is increased in response to glucose alongside an increase of the ADP:ATP ratio. They appear to close ATP sensitive potassium channels (KATP channels), causing a release of insulin secondary to calcium release. Both phosphocreatine and ADP are implicated, but it seems that despite the channel being sensitive to ATP, the concentration of ATP in a pancreatic cell (3-5mM) is already above the activation threshold (in the micromolar range) and thus a further increase would not have an appreciable effect.
In muscle cells, the creatine transporter is predominantly localized to the sarcolemmal membrane. Western blot analysis of creatine transporter expression revealed the presence of two distinc protein bands, migrating at 55kDa and 70kDa on reducing SDS-PAGE gels. The 73kDa band has been reported to be the predominant band in humans, with no differences based on gender. A more recent report demonstrated that the 55kDa creatine transporter variant is glycosylated, forming the 73 kDa protein. Therefore, the 55 and 75kDa protein bands are actually immature and mature/processed forms of the creatine transporter protein, respectively.
Beast Creature could be another good option for female athletes. It’s tasty, it contains five types of creatine, and it contains ingredients that could improve fat loss by increasing insulin sensitivity. One potential bonus is that it also has 70 percent of your daily biotin, a nutrient often included in women’s multivitamins due its purported benefits for hair and nails.
When you're in the middle of a strength-training session and something doesn't feel right to you, you feel pain, or if you hear or feel a "pop" during a workout, stop what you're doing. Have a doctor check it out before you go back to training. You may need to change your training or even stop lifting weights for a while to allow the injury to heal.
For the bench press, start with a weight that you can lift comfortably. If you are a beginner, try lifting the bar along with 5lbs or 10lbs on each side. With arms at shoulder-width apart, grab onto the bar and slowly lower the bar until it's at nipple level; push up until your arms are fully extended upwards. Do 8–10 repetitions (reps) like this for three sets (3 x 8), adding additional weight each set. Once you have a few months of practice, slowly increase weight and go down to 6–8 reps per set, aiming to reach muscle failure at the end of the third set.