Creatine is vital for brain function, which has mechanisms to take up creatine, as well as regulate its intake. Although the diet appears to be the major source of creatine (and thus lack of dietary intake could cause a non-clinical deficiency) excess levels of creatine do not appear to “super-load” the brain similar to muscle tissue. Due to kinetics, creatine appears to be more “preventative” or acts to restore a deficiency in the brain. This is in contrast to creatine effects in muscle cells, where it can affect performance substantially on an acute timescale.
Without supplementation, creatine is formed primarily in the liver, with minor contributions from the pancreas and kidneys. The two amino acids, glycine and arginine, combine via the enzyme Arginine:Glycine amidinotransferase (AGAT) to form ornithine and guanidoacetate. This is the first of two steps in creatine synthesis, and although rare, any deficiency of this enzyme can result in mild mental retardation and muscular weakness. AGAT is also the primary regulatory step, and an excess of dietary creatine can suppress activity of AGAT to reduce creatine synthesis by reducing AGAT mRNA levels, rather than resulting in competitive inhibition.
Despite the popularity of creatine among young people, there has been very little research conducted in children under age 18. Of those studies, a few have suggested a positive effect but the overall evidence is inconclusive. In one study, teenage swimmers performed better after taking creatine; in another study, it helped high school soccer players sprint, dribble, and jump more effectively.
These complete proteins include all of the essential amino acids that the body cannot produce itself. Different proteins, such as whey and casein, egg and soy have different absorption rates. Whether you should favor one over another for muscle building is still a subject of popular and scientific debate, although whey protein isolate, a more rapidly absorbed protein, has some support from various scientific studies. For protein powders, assess the value by checking out the protein listed on the label. Combined with resistance training, sufficient protein consumption along with an appropriate diet can lead to increased muscle and reduced body fat. You should read more about The Bodybuilding Diet for supplement timing issues before and after training.
Although weight training is similar to bodybuilding, they have different objectives. Bodybuilders use weight training to develop their muscles for size, shape, and symmetry regardless of any increase in strength for competition in bodybuilding contests; they train to maximize their muscular size and develop extremely low levels of body fat. In contrast, many weight trainers train to improve their strength and anaerobic endurance while not giving special attention to reducing body fat far below normal.
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.
I’m going to cover this in detail in a bit, but for right now, just know this: it’s VERY possible (and common) to gain weight fast in the hopes of gaining muscle fast. The problem, however, is that the majority of the “weight” a person in this scenario will end up gaining will be body fat rather than muscle mass. This is something that needs to be avoided at all costs, and I’ll show you how a little later.
One study investigating the effects of creatine supplementation on people with osteoarthritis undergoing knee arthroplasty (surgical procedure for osteoarthritis), who received creatine at 10g daily for 10 days prior to surgery and 5g daily for a month afterward, failed to find benefit with supplementation. This study failed to find any differences in muscular creatine stores or weight changes.
"It's especially important to eat a carb- and protein-rich meal immediately after a workout," Aceto says. "Right after training, it turns out that your body is really lousy at taking carbohydrates and sending them down fat-storing pathways," he says. "So post-training, carbs will be sent down growth-promoting pathways instead." And when these carbs are combined with a protein source, you've got a strong muscle-feeding combination because carbohydrates help deliver the amino acids into muscles by boosting insulin levels. This anabolic hormone drives nutrients into the muscle cells and kick-starts the muscle-growth process.
Increasing creatine levels in skeletal muscle to 687% of baseline (0.5mM creatine, thought to be equivalent to 5g creatine) doesn’t seem to per se increase glucose uptake, but increases glucose oxidation (140% of baseline) which is due to a two-fold increase in the activity of α1 and α2 subunits of AMPK, a potency comparable to 1mM of the reference drug AICAR. Glucose uptake associated with AMPK has indeed been noted in diabetic people who are undergoing physical exercise and in contracting skeletal muscle cells, but according to rat and in vitro studies of cells not being contracted, this is not a per se effect of non-exercising tissue but an augmentation of exercise-induced glucose uptake.
The harder an exercise is – both in terms of technicality and physical/mental demand – the more rest there should usually be. So exercises like squats and deadlifts should have more rest between sets than exercises like leg extensions and leg curls. And exercises like various bench presses, shoulder presses, rows and pull-ups should have more rest between sets than bicep curls, tricep extensions, chest flies and lateral raises.
Despite all the awesomeness of hypertrophy, athletes may be more interested in effects on power. Power is the ability to generate high amounts of force in relatively short periods of time — more power means you can pull more weight in low-rep sets — and independent of the hypertrophy, just five to ten grams of creatine per day appears to improve power output by 12 to 26 percent.
Creatine monohydrate is the most common form of creatine, and if not otherwise mentioned is the default form of creatine used in most studies on creatine. It has fairly decent intestinal absorption (covered more in depth in the pharmacology section) and is the standard form or “reference” form of creatine, which all other variants are pitted against.
Several review studies assessing the safety of creatine supplementation tend to make note of increases in formaldehyde and possible carcinogenic results. Specifically, creatine is metabolized into an intermediate called methylamine, which can be converted to formaldehyde by the SSAO enzyme. An increase in urinary formaldehyde has been noted in youth given 21g of creatine for one week, during which both methylamine (820% increase) and formaldehyde (350%) were increased, relative to control. However, a more prolonged study using 300mg/kg (loading dose of around 20g) in adults for ten weeks failed to replicate these effects.
Kerksick, C. M., Wilborn, C. D., Campbell, W. I., Harvey, T. M., Marcello, B. M., Roberts, M. D., Parker, A. G., Byars, A. G., Greenwood, L. D., Almada, A. L., Kreider, R. B., and Greenwood, M. The effects of creatine monohydrate supplementation with and without D-pinitol on resistance training adaptations. J.Strength.Cond.Res. 2009;23(9):2673-2682. View abstract.
It is prudent to note that creatine supplementation has been shown to reduce the body’s endogenous production of creatine, however levels return to normal after a brief period of time when supplementation ceases [1,6]. Despite this creatine supplementation has not been studied/supplemented with for a relatively long period. Due to this, long term effects are unknown, therefore safety cannot be guaranteed. Whilst the long term effects of creatine supplementation remain unclear, no definitive certainty of either a negative or a positive effect upon the body has been determined for many health professionals and national agencies [19,78]. For example the French Sanitary Agency has banned the buying of creatine due to the unproven allegation that a potential effect of creatine supplementation could be that of mutagenicity and carcinogenicity from the production of heterocyclic amines . Long term and epidemiological data should continue to be produced and collected to determine the safety of creatine in all healthy individuals under all conditions .
Kilduff, L. P., Georgiades, E., James, N., Minnion, R. H., Mitchell, M., Kingsmore, D., Hadjicharlambous, M., and Pitsiladis, Y. P. The effects of creatine supplementation on cardiovascular, metabolic, and thermoregulatory responses during exercise in the heat in endurance-trained humans. Int J Sport Nutr Exerc Metab 2004;14:443-460. View abstract.
A typical creatine supplementation protocol consists of a loading phase of 20 g CM/d or 0.3 g CM/kg/d split into 4 daily intakes of 5 g each, followed by a maintenance phase of 3-5 g CM/d or 0.03 g CM/kg/d for the duration of the supplementation period . Other supplementation protocols are also used such as a daily single dose of around 3 – 6 g or between 0.03 to 0.1 g/kg/d [15,55] however this method takes longer (between 21 to 28 days) to produce ergogenic effects . Sale et al  found that a moderate protocol consisting of 20 g CM taken in 1g doses (evenly ingested at 30-min intervals) for 5 days resulted in reduced urinary creatine and methylamine excretion, leading to an estimated increase in whole body retention of creatine (+13%) when compared with a typical loading supplementation protocol of 4 x 5 g/d during 5 days (evenly ingested at 3 hour intervals). This enhancement in creatine retention would lead to a significantly higher weight gain when people follow a moderate protocol ingestion of several doses of small amounts of CM evenly spread along the day.
In vitro studies on endothelial cells have noted that the benefits of creatine against atherosclerosis (via immune cell adhesion to the endothelial cell) are blocked with the pharmaceutical ZM241385, a high affintiy adenosine A2A receptor antagonist. This particular receptor subset (A2A rather than other adenosine receptors) and its inhibition are similar to caffeine, suggesting that caffeine may have an inhibitory effect on this mechanism of creatine.
Studies of so-called "smart drugs" have also been taken out of context. Some "smart" nutrients, available over the counter, are marketed as a way to "increase mental focus and concentration during training." The problem is that the studies they're based upon involved either animals or people with brain pathology. In normal people the effects of smart drugs remain unproven, except anecdotally.
In weight training, as with most forms of exercise, there is a tendency for the breathing pattern to deepen. This helps to meet increased oxygen requirements. Holding the breath or breathing shallowly is avoided because it may lead to a lack of oxygen, passing out, or an excessive build up of blood pressure. Generally, the recommended breathing technique is to inhale when lowering the weight (the eccentric portion) and exhale when lifting the weight (the concentric portion). However, the reverse, inhaling when lifting and exhaling when lowering, may also be recommended. Some researchers state that there is little difference between the two techniques in terms of their influence on heart rate and blood pressure. It may also be recommended that a weight lifter simply breathes in a manner which feels appropriate.
Stash away your scale for several weeks — and set a strength training goal instead. That’s the advice of Lisette Cifaldi, director of behavioral health at Hilton Head Health weight loss resort who counsels patients. “I think strength training shifts your perspective,” she says. “The happiness doesn’t come from achieving a certain number [on the scale]. It comes from the process of getting stronger and feeling empowered that you’re navigating your own success.”
The muscle endurance objective is pursued when you want your muscles to be able to perform the same motions over an extended period of time or in other words when you want your muscles to be strong and not become tired rapidly. You'll want to use at least 4 sets from which at least 16 repetitions are performed. The muscle endurance objective is often used for muscles in your lower body, such as those located in your legs or your buttocks.
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Walking, running, and swimming are examples of activity. Aerobic activity strengthens your heart and lungs. Stretching improves your flexibility. Strength training uses resistance, like free weights, weight machines, resistance bands, or a person's own weight, to build muscles and strength. Teens may want to strength train to improve sports performance, treat or prevent injuries, or improve appearance.