Do a single set of repetitions. Theories on the best way to approach weight training abound, including countless repetitions and hours at the gym. But research shows that a single set of exercise with a weight that fatigues your muscle after about 12 to 15 repetitions can build muscle efficiently in most people and can be as effective as three sets of the same exercise. 

In regard to carbohydrate oxidation during exercise, it appears that rats subject to intermittent physical exercise (which utilizes glycogen) have decreased lactate production during said exercise, suggesting a preservation of glycogen usage. This occurred alongside an increase in glycogen stores.[359] This is thought to be due to phosphocreatine donating phosphate to replenish ATP. Without any changes in whole body metabolic rate, it indirectly causes less glucose to be required to replenish ATP, due to a quota needing to be met during exercise and creatine phosphate taking up a relatively larger percentage of said quota.
Multivitamin supplements may help you reach the recommended daily intakes for vitamins and minerals if you have a less than ideal diet, travel impairs your diet, or strenuous exercise increases requirements. I consider a multivitamin good insurance in these circumstances against possible deficiencies. Choose a reputable brand. You should choose a good all-around supplement with a balanced formula.
When you’re doing higher reps, focus on the muscle you are trying to build and squeeze every ounce of effort out of it. Yes, cheesie as it may sound, visualizing the muscles working and growing while you train them can be helpful. A 2016 study in the European Journal of Applied Physiology found that, when lifters thought about their pecs and triceps during a workout, they activated them better.
There appears to be some potential for creatine supplementation. However, many questions remain. Are there any long-term harmful effects from supplementation? Is there a point where enhanced performance levels off from long-term supplement usage? What effect does "stacking" or taking two ergogenic aids simultaneously have on the body? What happens if you immediately stop taking the creatine supplement? Is the enhanced performance great enough to warrant the expense of the supplement? Until further research answers these questions, creatine is not recommended for the average athlete.
Remember, this is for the extreme skinny guy...But I want you to start hitting a buffet once a week. Try and position this eating frenzy after a hard workout so that the majority of calories get shuttled into the muscles which will really help you pack on those pounds and gain weight in the right places. Don't go too overboard, but this will train your body to 'accept' more food and it will increase your appetite in the days to come. Take advantage of this strategy.

When you’re planning your high-protein meals, 20 grams of protein is the optimal amount generally accepted for muscle growth. Research has found that the body doesn’t use much more than 20 grams for muscle-building at any one sitting. Around 80 grams of protein per day (or, four meals containing 20-grams of protein each) is about right for most people.

When looking specifically at human studies, there has been a failure of creatine supplementation to induce or exacerbate kidney damage in people with amyotrophic lateral sclerosis (ALS). Subjects do not experience kidney damage for up to or over a year’s worth of supplementation in the 5-10g range.[505][506][507] Postmenopausal women,[517] people with type II diabetes,[518] people on hemodialysis,[313] otherwise healthy elderly,[519] young people,[454][520][521] and athletes do not experience kidney damage either.[324] Moreover, numerous scientific reviews on both the long- and short-term safety of supplemental creatine have consistently found no adverse effects on kidney function in a wide range of doses.[522][523][524][452][525][451][526][527] However, while doses >10 g/day have been found not to impair kidney function, there are fewer long-term trials using such high chronic daily intakes.[527]
Prohormones are precursors to hormones and are most typically sold to bodybuilders as a precursor to the natural hormone testosterone. This conversion requires naturally occurring enzymes in the body. Side effects are not uncommon, as prohormones can also convert further into DHT and estrogen. To deal with this, many supplements also have aromatase inhibitors and DHT blockers such as chrysin and 4-androstene-3,6,17-trione. To date most prohormone products have not been thoroughly studied, and the health effects of prolonged use are unknown. Although initially available over the counter, their purchase was made illegal without a prescription in the US in 2004, and they hold similar status in many other countries. They remain legal, however, in the United Kingdom and the wider European Union. Their use is prohibited by most sporting bodies.
Bodybuilders often split their food intake for the day into 5 to 7 meals of roughly equal nutritional content and attempt to eat at regular intervals (e.g. every 2 to 3 hours). This method can serve two purposes: to limit overindulging in the cutting phase, and to physically allow for the consumption of large volumes of food during the bulking phase. Contrary to popular belief, eating more frequently does not increase basal metabolic rate when compared to the traditional 3 meals a day. While food does have a metabolic cost to digest, absorb, and store, called the thermic effect of food, it depends on the quantity and type of food, not how the food is spread across the meals of the day. Well-controlled studies using whole-body calorimetry and doubly labeled water have demonstrated that there is no metabolic advantage to eating more frequently.[38][39][40]
GLUTs are vesicle transporters that are the rate-limiting steps for bringing glucose into a cell, and GLUT4 is the most active variant.[327] Agents that reduce blood glucose (insulin or AMPK) are known to act via mobilizing GLUT4, and increased GLUT4 expression and activity is indicative of a greater ability to bring glucose into a cell, while reducing it impairs glucose uptake.[328] Rat studies have confirmed that creatine feeding increases muscular GLUT4 expression associated with increased insulin-stimulated glucose uptake.[329]
Bodybuilders have THE BEST mind to muscle connection of any resistance-training athletes. Ask a seasoned bodybuilder to flex their lats or their rhomboids or their hamstrings and they will do it with ease. Ask other strength athletes and you will see them struggle and although they may tense up the target muscle they will also tense up about 15 other surrounding muscles. This is because strength athletes train MOVEMENTS. They don’t care about targeting their lats. They just want to do the most pull ups. They don’t worry about feeling their quads. They just want to squat maximum weight. Although this is an expected and positive thing for the most part, there are real benefits to being able to isolate and target muscles.

Creatine is most commonly found in the basic form of creatine monohydrate, which is the standard form and usually recommended due to the low price. It can also be micronized to improve water solubility, or the monohydrate can be temporarily removed to concentrate creatine in a small volume supplement. Neither alteration changes the properties of creatine.
Specifically targeted to be used by natural bodybuilders and powerlifters, Universal Nutrition Animal M-Stak is the ideal supplement for hard-gainers. Containing ingredients that help promote protein synthesis while preventing muscle breakdown, Animal M-Stak is designed to naturally maximize the muscle mass building process. Optimize your performance and strength, and overcome your plateaus with Animal M-Stak. Keep Reading »
In females, the combination of SSRIs (to increase serotonin levels in the synapse between neurons) and creatine shows promise in augmenting the anti-depressive effects of SSRI therapy[230]. Another pilot study conducted on depression and females showed efficacy of creatine supplementation.[231] The one study measuring male subjects noted an increase in mood and minimal anti-depressive effects, but it is not know whether this is due to gender differences or the model studies (post-traumatic stress disorder).[232]
Weight training has also been shown to benefit dieters as it inhibits lean body mass loss (as opposed to fat loss) when under a caloric deficit. Weight training also strengthens bones, helping to prevent bone loss and osteoporosis. By increasing muscular strength and improving balance, weight training can also reduce falls by elderly persons. Weight training is also attracting attention for the benefits it can have on the brain, and in older adults, a 2017 meta analysis found that it was effective in improving cognitive performance.[38]
Who makes it: Creature is made by Beast Sports Nutrition, the fastest growing company in the entire sports nutrition industry. Their innovative products have taken the industry by storm, and the community response has been overwhelmingly positive. Beast Sports Nutrition makes a wide variety of fitness supplements, but they’re best known for Creature.
There are several different available forms of creatine: creatine anhydrous which is creatine with the water molecule removed in order to increase the concentration of creatine to a greater amount than that found in CM. Creatine has been manufactured in salt form: creatine pyruvate, creatine citrate, creatine malate, creatine phosphate, magnesium creatine, creatine oroate, Kre Alkalyn (creatine with baking soda). Creatine can also be manufactured in an ester form. Creatine ethyl ester (hydrochloride) is an example of this, as is creatine gluconate which is creatine bound to glucose. Another form is creatine effervescent which is creatine citrate or CM with citric acid and bicarbonate. The citric acid and bicarbonate react to produce an effervescent effect. When mixed with water the creatine separates from its carrier leaving a neutrally charged creatine, allowing it to dissolve to a higher degree in water. Manufacturers claim that creatine effervescent has a longer and more stable life in solution. When di-creatine citrate effervescent was studied [59] for stability in solution it was found that the di-creatine citrate dissociates to citric acid and creatine in aqueous solutions which in turn forms CM and eventually crystallises out of the solution due to its low solubility. Some of the creatine may also convert to creatinine.
Creatine supplementation may be able to enhance lifespan, secondary to increasing intracellular carnosine stores. Carnosine is the metabolic compound formed from beta-alanine supplementation, and in a mouse-model for premature aging (senescence-accelerated premature aging, SAMP8) creatine supplementation without any beta-alanine has been shown to increase cellular carnosine stores.[126] That being said, the aforemented SAMP8 study noted an increase in carnosine levels at middle age, but not old age in the mice.[126] A human study using 20g of creatine for one week in otherwise healthy people failed to find an increase in intracellular carnosine stores.[126]

In the last week leading up to a contest, bodybuilders usually decrease their consumption of water, sodium, and carbohydrates, the former two to alter how water is retained by the body and the latter to reduce glycogen in the muscle. The day before the show, water is removed from the diet, and diuretics may be introduced, while carbohydrate loading is undertaken to increase the size of the muscles through replenishment of their glycogen. The goal is to maximize leanness and increase the visibility of veins, or "vascularity". The muscular definition and vascularity are further enhanced immediately before appearing on stage by darkening the skin through tanning products and applying oils to the skin to increase shine. Some competitors will eat sugar-rich foods to increase the visibility of their veins. A final step, called "pumping", consists in performing exercises with light weights or other kinds of low resistance (for instance two athletes can "pump" each other by holding a towel and pulling in turn), just before the contest, to fill the muscles with blood and further increase their size and density.

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.
Side-Effects: While the signs of a great body may make one think that there cannot be anything wrong with bodybuilding supplements, the facts speak otherwise. Bodybuilding supplements do have side-effects and you must listen to your trainer before giving in to the thoughts of buying one. Creatine can cause heart problems, kidney problems, dehydration, diarrhoea and muscle cramping. You must also discuss your medical history with the trainer. 
Oral ingestion of 1-1000mg/kg bodyweight of creatine in mice was able to exert an anti-depressive effect, which was blocked by dopamine receptor antagonists. A low dose of creatine (0.1mg/kg) was able to enhance the dopaminergic effects of dopamine receptor activators, suggesting supplemental creatine can positively influence dopamine signaling and neurotransmission.[252]

Nephrotoxic drugs. Because taking high doses of creatine might harm your kidneys, there is concern about combining creatine with drugs that might damage the kidneys (nephrotoxic drugs). Potentially nephrotoxic drugs include nonsteroidal anti-inflammatory drug (NSAIDs) such as ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve, others), cyclosporine (Neoral, Sandimmune) and others.
Key point: Past a certain number of sets, the marginal increases in protein synthesis NO LONGER outweigh the cost of doing more sets. If 8 sets of chest exercises produce 95% of possible muscle protein synthesis… then it makes very little sense to do ANOTHER 10 sets (like most chest workouts) to try and inch out the final 5% of stimulation. Those extra 10 sets are simply damaging your muscle unnecessarily and impairing your ability to recover.
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(10):1772-1778. View abstract.
Parameters of lung function (main cause of death in ALS is declining respiratory function) have not benefited after creatine supplementation, and when quality of life is measured, there is no benefit either. Despite one study failing to find any significant differences in mortality risk, two other studies have suggested that creatine may reduce the risk. The results were nonsignificant, but due to all treatments being well tolerated it is thought that creatine may still play a role as an adjuvant.
Whenever you hear the word, “bodybuilding”, your mind usually flashes you images of bulging muscles, steel, sweat, the shouts of weightlifters, and ripped, muscular bodies of men and women in skimpy spandex. Your mind instantly takes you to the gym followed by wishful thinking that you can have a sexy body and bigger muscles. However, it takes more than just
In addition to improving athletic performance and muscle strength, creatine is taken by mouth for creatine deficiency syndromes that affect the brain, aging, bone density, chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), depression, diabetes, exercise tolerance, fibromyalgia, Huntington's disease, disease that cause inflammation in the muscles (idiopathic inflammatory myopathies), Parkinson's disease, diseases of the muscles and nerves, multiple sclerosis, muscle atrophy, muscle cramps, breathing problems in infants while sleeping, head trauma, Rett syndrome, an eye disease called gyrate atrophy, inherited disorders that affect the senses and movement, schizophrenia, muscle breakdown in the spine, and recovery from surgery. It is also taken by mouth to slow the worsening of amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease), osteoarthritis, rheumatoid arthritis, McArdle's disease, and for various muscular dystrophies.
Creatine is found in many protein supplements at baseline in the form of creatine monohydrate. If you take a protein supplement, you may already be getting creatine. What makes this creatine so special? Like the protein supplement above, this creatine supplement contains no artificial sweeteners or dyes. It contains 5000mg of creatine per dose and includes certain compounds to increase the bioavailability of the creatine, allowing it to be better absorbed.
Creatine is a naturally occurring compound found in muscle in large amounts. Creatine monohydrate is the supplement form and combines is a combination of the amino acids arginine, glycine, and methionine. Creatine drives the important creatine phosphate energy pathway, which is important in high-intensity activity such as weightlifting. Creatine can improve body bulk and training performance in high-intensity activities. Be aware that not everyone responds to creatine supplementation and 30 percent of users may not see any improvement. Women may not benefit as much as men. In weight training, increased strength, bulk, and fat loss are reasonably consistent results.
After your standard whey protein powder, creatine may be the most popular sports supplement on Earth, and with good reason. A lot of supplements out there have a few promising studies suggesting they may improve some aspect of performance. Creatine has hundreds of them, and study after study has shown that among most people (a small percentage of are non-responders) it can have a significant effect on several areas of performance.
This muscle-building, power-enhancing supplement has an extremely high safety profile and a plethora of evidence to support its efficacy. Creatine supplementation works by increasing the availability of creatine and phosphocreatine (PCr) within the muscle, helping to maintain energy during high-intensity exercise such as weightlifting. Furthermore, increasing the availability of PCr may help speed up recovery between sets.
In addition to ALL of the above, strength training is fun! Whether you are looking for the most effective 20-30 minute workout (to stay fit and look great naked), or are looking for a competitive sport that you can really get into, strength training can help you meet your goals. It’s easy and fun to see progress as you strength train, almost like leveling up. And if you’re looking to improve in other areas (a sport, traditional cardio, or an activity like rock climbing), strength training is an easy choice!
The first open label trial on ALS failed to significantly alter lung function as assessed by FEV (when comparing the rate of decline pretreatment relative to treatment).[545] Creatine has elsewhere failed to benefit lung function at 5g daily for months relative to control[546] and failed to significantly attenuate the rate of lung function deterioration over 16 months at 10g daily[505] and 5g daily over nine months.[507]

How long and how often? Two or three weekly 20- to 30-minute, weight-training sessions are sufficient to start reaping noticeable benefits within four to 12 weeks, such as improved energy and muscle tone. Within six months, most people increase their strength 40 percent or more. Give your body at least one recovery day between sessions (although some people may need more, especially in the beginning).

Take your vitamins. In addition to a well-balanced diet, include a multivitamin supplement to your dietary regimen. It will ensure that your body is getting the full amount of vitamins and minerals it needs to stay healthy. There are many options, depending on your age, your sex, and your particular health and diet needs. Find the one that's right for you, and make it part of your daily routine.
Many athletes follow a "loading" protocol of around 25 grams a day for five days, but this isn't essential. But as Ciaran Fairman notes in the article "Do I Need to Load With Creatine," you can also get the same benefits with around 5 grams a day, potentially with none of the mild side effects of the loading protocol, which include stomach pain and water weight gain. The catch is that you have to take it consistently. Don't skip it!
Deldicque et al [32] found a 250%, 45% and 70% increase for collagen mRNA, glucose transporter 4 (GLUT4) and Myosin heavy chain IIA, respectively after 5 days creatine loading protocol (21 g/d). The authors speculated that creatine in addition to a single bout of resistance training can favor an anabolic environment by inducing changes in gene expression after only 5 days of supplementation.
Now, while all three are definitely beneficial to the process, I’d consider metabolic stress and muscular damage to be of secondary and tertiary importance, respectively. In addition, they are also things that will pretty much take care of themselves when implementing the workout guidelines and recommendations we’ve already covered (namely for volume, rep ranges, rest periods and exercise selection).
The reasons for differences in the effect of creatine on testosterone vs. DHT across studies are not clear, but also not mutually exclusive. A measured increase in DHT could indicate that testosterone levels were increased by creatine, but rapidly converted to DHT through a homeostatic mechanism. Differences in study subject populations, methodology, or the presence and type of concurrent exercise could also be contributing factors. At any rate, the literature collectively suggests that creatine has the general ability to cause a modest increase in androgen levels in men.
Consult your physician and follow all safety instructions before beginning any exercise program or using any supplement or meal replacement product, especially if you have any unique medical conditions or needs. The contents on our website are for informational purposes only, and are not intended to diagnose any medical condition, replace the advice of a healthcare professional, or provide any medical advice, diagnosis, or treatment.
For several years, research studies have shown that adolescents concerned with both athletics and appearance are taking performance-enhancing supplements. A study by the American Academy of Pediatrics of middle-school and high-school students ages 10 to 18 years found creatine use in all grades 6 through 12. About 5.6% of the study participants and 44% of high-school senior athletes admitted taking creatine.
As Heath talked in the office, Cremona presented him with steak and white rice. It was takeout, from Outback Steakhouse, because the two had just returned from a weeklong trip. Heath reached toward a bouquet of round plastic jars filled with powdered supplements. He scooped powder from one into a water bottle, shook it and drank. He compared himself to a racecar, always in need of fuel and delicate tinkering.
There is a great amount of research published on creatine supplementation; protocols of administration, forms of creatine, as well as potential side effects. Despite this, the mechanisms by which creatine acts in the human body to improve physical and cognitive performance are still not clear. The main objectives of this review are to analyze the more recent findings on the effects and mechanisms of creatine supplementation in sports and health. As a secondary purpose, we will analyze the most recommended protocols of ingestion and its potential side effects.
The major controversies regarding creatine are its side effects and the best form to use. Nearly all side effects attributed to creatine, such as muscle cramps, kidney disease and gastrointestinal disturbances, haven't proved significant under controlled scientific scrutiny. Although various claims are made for a variety of creatine supplements, creatine monohydrate, which is 99 percent absorbed, is the best form to use.
Yes, genetically some of us put on muscle faster than others, but even then it’s fractions of a degree, not DRASTIC sweeping differences. We tend to get this question from men or women who are so thin and have such fast metabolisms, they probably need to put on 40-50+ pounds of both fat and muscle, before they would ever even think to use the word “too bulky.”
This muscle-building, power-enhancing supplement has an extremely high safety profile and a plethora of evidence to support its efficacy. Creatine supplementation works by increasing the availability of creatine and phosphocreatine (PCr) within the muscle, helping to maintain energy during high-intensity exercise such as weightlifting. Furthermore, increasing the availability of PCr may help speed up recovery between sets.
Translation: your muscles are going to have more energy. The process of accessing that energy is so complicated, you almost need an organic chemistry degree to totally understand it. Yes, it’s complicated, but completely necessary for biochemical reactions like muscle contractions. And the more your muscle works, the more ATP is depleted and needs to be replaced for you to make progress toward your goals. With creatine supplementation, you can enhance your ATP regeneration and thus delay onset of muscle fatigue and work more intensely for a longer period of time. Little goes a long way in the pursuit of muscle gains.
By increasing the overall pool of cellular phosphocreatine, creatine supplementation can accelerate the reycling of ADP into ATP. Since ATP stores are rapidly depleted during intense muscular effort, one of the major benefits of creatine supplementation is its ability to regenerate ATP stores faster, which can promote increased strength and power output. Over 95% of creatine is stored in muscle at a maximum cellular concentration of 30uM. Creatine storage capacity is limited, though it increases as muscle mass increases.[24] A 70 kg male with an average physique is assumed to have total creatine stores of approximately 120g.[25] The body can store a lot more energy as glycogen in the liver, brain, and muscles,[26][27] and even more as fat.

At the end of the day, yes, strength training does impact your metabolism, but any boost you get will be minimal and completely secondary to all of the other health benefits of strength training. Any change in metabolism or increase in calorie burn will vary widely from person to person, and depends on so many factors: your genetics, eating habits, health conditions, what workout you do that day, how much sleep you’re getting, and even how stressed you are on any given day. But incorporating a couple of strength training sessions into your fitness routine is worth doing no matter what—you’ll feel yourself get stronger, and put yourself in a position to say healthier throughout life. Those are the best, most promising benefits to work for.
Moving through repetitions too quickly, going too fast; there is nothing gained by lifting weights fast. Some of the perks of lifting weight in a slow and controlled manner, include more total muscle tension and force produced, more muscle-fiber activation both slow and fast twitch fibers, and less tissue trauma. Remember, a joint is only as strong as the muscles that cross it; if you haven't lifted in a long time, or ever, be careful what you ask of your joints.
Over time, we naturally lose muscle mass in a process called sarcopenia. On average, men lose about 30% of their muscle mass during their lives. Usually, this begins in your 30s and progresses slowly as you age. But, don’t despair. You can rebuild and maintain muscle mass even as you age. Often, diet and exercise are enough. But, sometimes, if the above hormones play a role, your doctor may recommend medications and additional treatments (4).
A: Depending upon your experience level, preference, recovery capacity, and time available, you’ll likely find that 3-5 strength training sessions per week is the sweet spot. If you’re just getting started with weight training, then you should stick with 3 days per week and work your way up. Novices and early intermediates can handle 4 days per week with a split such as an upper lower and seasoned intermediate lifters may be able to handle 5 sessions per week depending upon the programming, recovery, and nutrition strategies that are in place.
Homocyteine (normal serum range of 5-14µM) is known to adversely affect motor control in genetically susceptible people when their levels exceed 500µM, which is usually associated with genetically induced deficiencies of B12.[360][361] In these particular instances (assessed by rats fed homocysteine to increase serum levels to such a high level[362][363]) it appears that administration of 50mg/kg creatine (injections) to these rats can protect dysfunction in muscle metabolism (pyruvate kinase activity, Krebs cycle intermediates, and muscle cell viability) induced by homocysteine.[363]
Creatine was first identified in 1832 when Michel Eugène Chevreul isolated it from the basified water-extract of skeletal muscle. He later named the crystallized precipitate after the Greek word for meat, κρέας (kreas). In 1928, creatine was shown to exist in equilibrium with creatinine.[3] Studies in the 1920s showed that consumption of large amounts of creatine did not result in its excretion. This result pointed to the ability of the body to store creatine, which in turn suggested its use as a dietary supplement.[4]
It’s not just about lifting—it’s about lifting safely and correctly. And if you’re not performing exercises properly, it’s impossible to make any progress. “When someone is just starting to work out, it can help to work closely with a knowledgeable personal trainer in order to learn proper form,” says Ingram. But that goes for experienced lifters, too. If you aren’t sure about a movement, it’s better to ask. “If you’re not working the correct muscles, you can’t expect them to grow,” explains Ingram.
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. 
The incidence of liver damage from herbal and dietary supplements is about 16–20% of all supplement products causing injury, with the occurrence growing globally over the early 21st century.[2] The most common liver injuries from weight loss and bodybuilding supplements involve hepatocellular damage with resulting jaundice, and the most common supplement ingredients attributed to these injuries are catechins from green tea, anabolic steroids, and the herbal extract, aegeline.[2]

The creatine transporter (CrT) is positively regulated by proteins known to be involved in sensing and responding to the cellular energy state, including the mammalian target of rapamycin (mTOR[158]). Upon activation, mTOR stimulates SGK1 and SGK3[159][160] to act upon PIKfyve[161] and subsequently PI(3,5)P2[162] to increase CrT activity.[161] Beyond mTOR, SGK1 also is stimulated by intracellular calcium[163] and a lack of oxygen (ischemia).[164] Because transient ischemia is associated with increased reactive oxygen species (ROS) production after blood flow is restored (reperfusion) it has been hypothesized that muscle contraction may increase creatine uptake through a similar ROS-mediated mechanism.[165]

Spero Karas, MD, assistant professor of orthopaedics in the division of sports medicine at Emory University, says that testosterone, the male hormone responsible for muscle growth, maxes out between the ages of 16 and 18. It reaches a plateau during the 20s and then begins to decline. As a result, muscle building after the adolescent years can be challenging, he says.

Collectively the above investigations indicate that creatine supplementation can be an effective strategy to maintain total creatine pool during a rehabilitation period after injury as well as to attenuate muscle damage induced by a prolonged endurance training session. In addition, it seems that creatine can act as an effective antioxidant agent after more intense resistance training sessions.