Carducci, C., Birarelli, M., Leuzzi, V., Carducci, C., Battini, R., Cioni, G., and Antonozzi, I. Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies. Clin Chem 2002;48:1772-1778. View abstract.
It’s true—your genes can play a role when it comes to building muscle. In general, there are two types of muscle fibers: Type I, which are slow twitch, and Type II, which are fast twitch. Depending on which you have more of, you may have an easier or harder time gaining muscle. “Fast twitch muscle fibers are two times as thick as slow twitch muscle fibers, lending to the overall thickness of the muscle without any activity,” explains Lovitt. “Those people with a genetic predisposition of a high percentage of these fibers can increase muscle size very easily while the people with a higher percentage of slow twitch muscle fibers have to work really hard to put on mass.” It’s the reason why a world-class sprinter genetically has more fast twitch muscle fibers than a world-class marathoner—it comes down to what we’re born with.
Carbohydrates provide quick energy in an anaerobic environment (high-intensity exercise), while fats provide sustained energy during periods of high oxygen availability (low-intensity exercise or rest). The breakdown of carbohydrates, fats, and ketones produces ATP (adenosine triphosphate). When cells use ATP for energy, this molecule is converted into adenosine diphosphate (ADP) and adenosine monophosphate (AMP). Creatine exists in cells to donate a phosphate group (energy) to ADP, turning this molecule back into ATP.
Weight gain might be the most common side effect. “Creatine can cause your body to hold on to water by pulling fluid into your cells via osmosis,” says Bates. “It doesn't necessarily cause you to gain weight as fat, but it can increase edema, or water weight.” Also, muscle is denser than fat, so in some cases building muscle can increase body weight overall (even if you’re simultaneously burning fat).
Older women with knee osteoarthritis given supplemental creatine at 20g for five days followed by 5g for the rest of the twelve week trial experienced improvements in stiffness (52% reduction), pain (45%), and physical function (41%) as assessed by WOMAC, despite no improvements in physical power output relative to placebo. This study paired supplementation and placebo with a mild exercise regimen.
^ Spillane M, Schoch R, Cooke M, Harvey T, Greenwood M, Kreider R, Willoughby DS (February 2009). "The effects of creatine ethyl ester supplementation combined with heavy resistance training on body composition, muscle performance, and serum and muscle creatine levels". Journal of the International Society of Sports Nutrition. 6 (1): 6. doi:10.1186/1550-2783-6-6. PMC 2649889. PMID 19228401.
In a pilot study on youth with cystic fibrosis, supplementation of creatine at 12g for a week and 6g for eleven weeks afterward was associated with a time-dependent increase in maximal isometric strength reaching 14.3%, which was maintained after 12-24 weeks of supplement cessation (18.2% higher than baseline). This study noted that more patients reported an increase in wellbeing (9 subjects, 50%) rather than a decrease (3, 17%) or nothing (6, 33%) and that there was no influence on chest or lung symptoms.
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.
The NitroSurge pre-workout supplement by Jacked Factory aims to get you pumped and focused before a gym session. Besides L-Citrulline, this supplement also contains performance-enhancing betaine anhydrous and beta alanine. It also contains L-theanine which has shown to inhibit nerve cell damage in one study. For energy-boosting benefits, the NitroSurge is also equipped with caffeine and AstraGin for energy metabolism. Before you buy, consider if you fall under the following circumstances in which this pre-workout would be beneficial to you:
High extracellular creatine concentrations induce the expression of a factor that inhibits the creatine transporter (CrT). To date, neither the identity of nor mechanism for this putative CrT-suppressing factor has come to light. Future studies that are able to identify this creatine transport-suppressing factor and how it works may provide valuable insight into possible supplementation strategies that might be used to increase creatine uptake into muscle cells.
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. Neutrophils and macrophages were unaffected, reflecting the past study of no influence on macrophages, 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.
Chin-Ups. The chin-up is the easiest way to determine someone’s relative strength. If you can knock out sets of bench with your bodyweight but can’t perform at least 5 bodyweight chin-ups then it’s time to re-evaluate your priorities. Chin-ups are an excellent mass builder for the lats, biceps, and upper back so they should take the place of machine variations like lat pulldowns whenever possible.
How much of a difference does EPOC make? Well, in one research study of young women, basal metabolic rate spiked by 4.2 percent 16 hours following a strength-training session that lasted an hour and 40 minutes—the equivalent of burning an extra 60 calories, on average. That’s a long workout, and 60 extra calories isn’t exactly huge. Plus, EPOC is not a permanent boost. Research suggests it may last anywhere from 12 hours to a few days, depending on the workout and who is doing it. The calories you burn through EPOC can add up over time, especially if you’re lifting weights three or four times a week, but all in all, it doesn’t have a very big effect on your metabolism.
This period also saw the rise of anabolic steroids in bodybuilding and many other sports. In bodybuilding lore, this is partly attributed to the rise of "mass monsters", beginning with Arnold Schwarzenegger, Sergio Oliva, and Lou Ferrigno in the late 1960s and early 1970s, and continuing through the 1980s with Lee Haney, the 1990s with Dorian Yates, Ronnie Coleman, and Markus Rühl, and up to the present day. Bodybuilders such as Greg Kovacs attained mass and size never seen previously but were not successful at the pro level. Others were renowned for their spectacular development of a particular body part, like Tom Platz or Paul Demayo for the leg muscles. At the time of shooting Pumping Iron, Schwarzenegger (while never admitting to steroid use until long after his retirement) said that "you have to do anything you can to get the advantage in competition". He would later say that he does not regret using anything.
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.
Despite a possible decreasing creatine content in the muscles when maintenance is deemed suboptimal, the overall retention of weight and lean mass is merely additive over time. This is thought to be due to increases in skeletal muscle production (increase in body weight) compensating for the progressive declines in water and glycogen content (decreases in body weight).
A study showed that 100mg/kg creatine monohydrate daily over four months supplemented by boys with DMD is able to enhance handgrip strength in the dominant hand only (less than 10% increase) and increase whole-body lean mass. While the trend toward whole body strength reduction seen in placebo was ablated and there was no interaction with corticosteroids, this study failed to find an influence on activities of daily living or lung function. Elsewhere in children not on corticosteroids with DMD, supplementation of 5g creatine for eight weeks was confirmed to increase muscular phosphocreatine content and according to a manual muscle test (MMT) there was a significant improvement in muscular function relative to placebo, with more parents reporting benefit with creatine (53.8%) relative to placebo (14%).
Generally, you should consume about 20 grams of protein with some carbs shortly after a workout. During the post-workout anabolic window, you’ll also want to limit fats, which can slow the absorption of protein. While there is some recent research that suggests the window may actually extend up to several hours following exercise, there’s no harm in getting nutrients in early as long as you’re sticking to your overall caloric and macronutrient goals.
During the 1950s, the most successful and most famous competing bodybuilders[according to whom?] were Bill Pearl, Reg Park, Leroy Colbert, and Clarence Ross. Certain bodybuilders rose to fame thanks to the relatively new medium of television, as well as cinema. The most notable[according to whom?] were Jack LaLanne, Steve Reeves, Reg Park, and Mickey Hargitay. While there were well-known gyms throughout the country during the 1950s (such as Vince's Gym in North Hollywood, California and Vic Tanny's chain gyms), there were still segments of the United States that had no "hardcore" bodybuilding gyms until the advent of Gold's Gym in the mid-1960s. Finally, the famed Muscle Beach in Santa Monica continued its popularity as the place to be for witnessing acrobatic acts, feats of strength, and the like. The movement grew more in the 1960s with increased TV and movie exposure, as bodybuilders were typecast in popular shows and movies.
Creatine has been found to increase skeletal muscle glycogen when given to sedentary adults for a loading and maintenance phase for 37 days at 2g (13.5% after five days of loading, but returning to baseline at the end of the trial). Exercise was not enforced in this study. This study also noted that, despite a normalization of glycogen after the trial, total creatine and ATP was still higher than placebo, and a loading protocol appears to have failed elsewhere in increasing glycogen stores in sedentary people subject to an aerobic exercise test before and after the loading phase.
Eat 0.4–0.5 grams of fat per pound of your body weight. Fat is essential for hormone optimization, brain function, and joint health. Now, if you’re following a ketogenic diet (or modified keto diet), or you just feel better with more fat in your diet, you can certainly add more fat and lower your protein and carb intake to accommodate it. The 0.4–0.5 grams per pound recommendation just represents a starting point and a minimum so that you don’t eat too little fat, either out of fear that it will make you fat or damage your heart (both untrue). For more about ketogenic diets, see Onnit’s guide HERE.
After supplementation of creatine monohydrate (loading phase, followed by 19 weeks maintenance), creatine precursors are decreased by up to 50% (loading) or 30% (maintenance), which suggests a decrease in endogenous creatine synthesis during supplementation. This appears to occur through creatine’s own positive feedback and suppression of the l-arginine:glycine amidinotransferase enzyme, the rate-limiting step in creatine synthesis, as levels of intermediates before this stage are typically elevated by up to 75%.