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).
I HATE that the resistance training community can be so tribal. I have been preaching to bodybuilders for years about the benefits of powerlifting, or Olympic lifting or kettlebells or even Crossfit style conditioning and many have been receptive. Learn from each other and achieve levels of fitness you simply could not have otherwise. Don’t brush off bodybuilding wisdom…it could be the missing factor in your program.
Aim to eat roughly 250 to 500 extra calories per day. To make sure that any weight gained is from muscle, Fitzgerald recommends that the bulk of those calories come from protein. In a 2014 Pennington Biomedical Research Center study, people who ate a high-calorie diet rich in protein stored about 45 percent of those calories as muscle, while those following a low-protein diet with the same number of calories stored 95 percent of those calories as fat.
If you are referring to how many pushups to do in one session, the short answer is as many as you can. Aim for a number that challenges you but is still realistic. Build up from day to day to increase muscle strength. If you are referring to how long you should do pushups as a form of exercise, that is up to you. Pushups are a good part of a long-term or permanent exercise regimen. Remember that if you stop doing them, your muscles will weaken.
This increased permeability is noted in glioma cells, where it exerts anti-cancer effects related to cell swelling,[99][100] and in other membranes, such as breast cancer cells[101] and skeletal (contractile) muscle cells.[102] The kinetics of cyclocreatine appear to be first-order,[101] with a relative Vmax of 90, Km of 25mM and a KD of 1.2mM.[103]
The concentration in healthy controls (57+/-8 years) without supplementation of creatine appears to be around 1.24+/-0.26µM per gram of hemoglobin[292] and appears to decrease in concentration during the aging process of the erythrocyte.[294][295][296] Otherwise healthy subjects who take a loading phase of creatine (5g four times daily for five days) can experience a 129.6% increase in erythrocytic creatine concentrations from an average value of 418µM (per liter) up to 961µM with a large range (increases in the range of 144.4-1004.8µM),[297] and this effect appears to correlate somewhat with muscular creatine stores.[297]
Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects.[26] Clinically, there are three distinct disorders of creatine metabolism. Deficiencies in the two synthesis enzymes can cause L-arginine:glycine amidinotransferase deficiency caused by variants in GATM and guanidinoacetate methyltransferase deficiency, caused by variants in GAMT. Both biosynthetic defects are inherited in an autosomal recessive manner. A third defect, creatine transporter defect, is caused by mutations in SLC6A8 and inherited in a X-linked manner. This condition is related to the transport of creatine into the brain.[27]
Beach muscles and Olympic lifts draw more attention. But the many little stabilizer muscles around your shoulders, hips, and midsection — collectively the core — provide a strong foundation. Challenging the stability and mobility of these key muscles with medicine balls, physioballs, mini-bands, and rotational movements (lifting, chopping) pays huge dividends.
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.

For example, a 2015 review published in the peer-reviewed journal Applied Physiology, Nutrition, and Metabolism suggests that, for maximal muscle growth, people consume 25 to 35 grams of protein at breakfast, lunch and dinner. You'll find that amount of protein in a chicken breast, a cup of Greek yogurt with slivered almonds or about a three-quarter block of tofu.


A muscle imbalance—when one muscle is stronger than its opposing muscle—can limit your ability to exercise effectively, and could lead to injury down the line. “It’s important to recognize whether you’re really working the muscles you think you are and recognize if you’ve developed an imbalance that alters your movement pattern,” says Eric Ingram, physical therapist at Louisiana Physical Therapy Centers of Pineville. One common imbalance in women is stronger quads and weaker, tighter hamstrings, thanks to prolonged sitting, high heels, and improper training. If you suspect you have a muscle imbalance, make an appointment with a physical therapist, who will prescribe exercises to even you out.
Take time to rest. To give your muscles time to recover, rest one full day between exercising each specific muscle group. You might choose to work the major muscle groups at a single session two or three times a week, or plan daily sessions for specific muscle groups. For example, on Monday work your arms and shoulders, on Tuesday work your legs, and so on.

However, don’t despair over the poor reviews. There are other ways to achieve a testosterone booster for muscle gain. One of them is simply Vitamin D. A deficiency in this vitamin can lower your levels of testosterone. Furthermore, you can get a very natural boost simply by weightlifting and engaging in HIIT (High Intensity Interval Training) exercise. In addition, you should avoid some foods like soy and alcohol which can lower testosterone levels (11). Through these natural solutions and lifestyle changes, you can influence your hormone profile, creating a balance that’s more favorable for muscle growth.
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).
Creatine is only taken up by its transporter, and changes in the activity level of this transporter are wholly causative of changes in creatine uptake. The transporter is regulated by mostly cytosolic factors as well as some external factors that affect creatine transport activity, [143] including extracellular creatine.[140] Agents affecting creatine transport are further divided into positive regulators (those that increase activity of the transporter) and negative regulators (those that suppress activity).
Previous investigations have shown that a single dose of CM (8 grams) increased the number of repetitions performed during an upper-body resistance training protocol and reduced soreness at 24 and 48 hours post-exercise (compared to a placebo).7 Recently, researchers from Mississippi State University found that a single dose of CM (8 grams) significantly increased the number of lower-body repetitions compared to a placebo group.[8]
In 1912, Harvard University researchers Otto Folin and Willey Glover Denis found evidence that ingesting creatine can dramatically boost the creatine content of the muscle.[5][non-primary source needed] In the late 1920s, after finding that the intramuscular stores of creatine can be increased by ingesting creatine in larger than normal amounts, scientists discovered creatine phosphate, and determined that creatine is a key player in the metabolism of skeletal muscle. The substance creatine is naturally formed in vertebrates.[6]
Anti-cancer effects have been observed with the creatine analogue cyclocreatine[456][104][457] and have been replicated with creatine itself. These effects tend to be a reduction in which the rate of implanted tumors progresses.[458][459] It is suspected that these observed effects (inhibition of growth or attenuation of the rate of growth) are not due to the bioenergetic effect of creatine, secondary to creatine kinase. These anti-cancer effects do not have a known reliability, as the expression of creatine kinase varies widely based on the type of tumor.[460] However, some studies suggest an inverse relationship between tumor progression in mice and concentrations of creatine in cells, with creatine depletion coinciding with tumor development.[460]
To see if ShippingPass is right for you, try a 30-day free trial. Also, with ShippingPass, there is no need to worry about commitment. If you decide you want to discontinue the service, you can cancel your subscription at any time. No matter what your shipping needs, Walmart's got you covered. Sign up for ShippingPass so you can shop more, save money and live better.
Skin degradation is caused by a loss of collagen and degradation of the extracellular matrix,[536] which is enhanced by UV radiation (produces reactive oxygen species which stimulate MMPs[537]) and contributes to skin integrity loss and wrinkling. Due to the stimulation of collagen being associated with a cellular surplus of energy[538] and intracellular stores of energy declining with age,[539][540] creatine has been investigated as a topical anti-aging agent. In vitro, creatine appears to be rapidly absorbed through the skin (52% within an hour, remaining similar at 3 hours) with most creatine found in the stratum corneum (79.6-86.5%) follwed by the epidermis (9-13.2%) and dermis (4.5-7.1%).[541] It is successful in stimulating collagen expression and procollagen secretion in fibroblasts, with the latter increasing to 449+/-204% of control.[541]
Heath is an unlikely Mr. Olympia. He grew up on playgrounds in Seattle playing basketball. His backcourt mate on the 1998 state championship team at Rainier Beach High School was Jamal Crawford, still in the N.B.A. Heath, just 5 feet 9 inches and a naturally chiseled 175 pounds, got a Division I basketball scholarship at the University of Denver. He majored in business and averaged 1.3 points over four seasons.
Creatine has been shown to influence androgen levels. Three weeks of creatine supplementation has been shown to increase dihydrotestosterone (DHT) levels, as well as the DHT:testosterone ratio with no effects on testosterone levels.[430] In contrast, creatine supplementation has been shown to increase testosterone levels when taken alongside a 10-week resistance training program.[431] A study in male amateur swimmers also noted that a creatine loading phase (20g daily for six days) was able to increase testosterone levels by around 15% relative to baseline.[397] 
Researchers described the study as one of the first to examine how strength training can reduce the risk of cardiovascular disease, separate from the effects of aerobic activity like running or long walks. The point: for those who are not meeting recommended guidelines for aerobic activity—perhaps because they lack the time—bursts of weight training can be enough.
You can't scroll through Instagram without clocking a mammoth cheat day feast, but are real-life bodybuilders consuming such a crazy amount of calories every couple of weeks? Not quite. When he’s dieting for a competition, Terry incorporates ‘re-feed days’ into his schedule. This means he eats the exact same food, but essentially doubles the portion sizes.
It can be hard to know where to start when beginning strength training. There are countless exercises you can do, some of which work some muscles, but not others. There are safety concerns to beware of, a wide variety of sometimes confusing equipment to help you in your efforts, and so on. With some familiarity of the basics of getting started with strength training, actually doing so can become far less daunting, and you can begin to craft a routine that is targeted toward helping you achieve your personal goals.

However, the basis of “take creatine after your workout” comes from a 2013 study published in the JISSN, which can be found here (open access too!). In this study, recreational male bodybuilders (19 men overall) were given five grams of creatine either before or after their workouts. They trained five days per week but were also directed to consume 5g on their rest days at any time they wanted. The workouts were fairly similar to most gym workouts, and the methodology (what they did and how they did it) suggests that the findings would apply to most weightlifters.


Those micro-tears that are such a key factor for muscle-building need rest to rebuild themselves and grow stronger. When do they do that? When you’re asleep! “You have to rest and feed your muscles between workouts or you will tear them down and they will become weaker,” says Olson. “Over time, you run the risk of over-training, which can result in injury, and possibly even more sleep troubles.”
^ Jump up to: a b c Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM (2017). "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults". Br J Sports Med. 52 (6): bjsports–2017–097608. doi:10.1136/bjsports-2017-097608. PMC 5867436. PMID 28698222.
In fact, in one new study comparing the effects of aerobic exercise versus resistance training on the psychological health of obese adolescents, researchers found that people in the resistance group experienced significantly greater self-esteem and perceived strength over four weeks. But what’s most interesting is that the feeling of getting stronger — rather than any measurable gains — was all it took to give them a boost.
Finally, starvation (nutrient deprivation for four days) appears to increase activity of the creatine transporter secondary to decreasing serine phosphorylation (SGK target)[173] with no influence on tyrosine phosphorylation (c-Src target).[173] Starvation-induced increases in creatine influx do not necessarily mean more phosphocreatine, however, due to a depleted cellular energy state.[173]

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.


Research shows that strength training is especially effective at raising EPOC. That’s because, generally speaking, strength-training sessions cause more physiological stress to the body compared to cardiovascular exercise, even higher-intensity cardio intervals. However, it’s worth noting that overall exercise intensity is what makes the biggest impact on EPOC. So squats, deadlifts, and bench presses with heavy weights are going to be much more effective at raising EPOC compared to bicep curls and triceps extensions with light weights.
There's good news, though: These temporary muscle pumps are critical to improving muscle hypertrophy, or muscle growth, according to 2014 research in the Strength and Conditioning Journal. So you can think of your weight-room pump as a preview of the muscle results that are to come. Speaking of which, here's an expert-endorsed timeline to reach your muscle-building goals.
Maintaining proper form is one of the many steps in order to perfectly perform a certain technique. Correct form in weight training improves strength, muscle tone, and maintaining a healthy weight. Proper form will prevent any strains or fractures.[6] When the exercise becomes difficult towards the end of a set, there is a temptation to cheat, i.e., to use poor form to recruit other muscle groups to assist the effort. Avoid heavy weight and keep the number of repetitions to a minimum. This may shift the effort to weaker muscles that cannot handle the weight. For example, the squat and the deadlift are used to exercise the largest muscles in the body—the leg and buttock muscles—so they require substantial weight. Beginners are tempted to round their back while performing these exercises. The relaxation of the spinal erectors which allows the lower back to round can cause shearing in the vertebrae of the lumbar spine, potentially damaging the spinal discs.
Creatine supplementation appears to augment the anti-cancer effects of Vitamin C and methylglyoxal,[463] a metabolic by-product of glycolysis.[464] Methylglycoxal appears to inhibit step 1 of the electron transport chain in isolated mitochondria and cancerous mitochondria, but has not been implicated in doing so in normal tissue, as protective measures in normal cells appear to exist.[465][464]
Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects.[26] Clinically, there are three distinct disorders of creatine metabolism. Deficiencies in the two synthesis enzymes can cause L-arginine:glycine amidinotransferase deficiency caused by variants in GATM and guanidinoacetate methyltransferase deficiency, caused by variants in GAMT. Both biosynthetic defects are inherited in an autosomal recessive manner. A third defect, creatine transporter defect, is caused by mutations in SLC6A8 and inherited in a X-linked manner. This condition is related to the transport of creatine into the brain.[27]
That being said, men aren’t the only ones who suffer from low testosterone levels. Women can also suffer from testosterone deficiency which can affect their overall well-being in addition to their sex drive. If you’re a woman or man concerned about your testosterone levels, in addition to using supplements like the ones below, you should contact your doctor who will be able to diagnose any deficiencies and recommend additional treatments.

Beta-alanine is a naturally occurring non-essential amino acid that comes into the body through foods that are rich in protein. The performance-enhancing aspect of beta-alanine (BA) is due to its ability to increase intra-muscular levels of carnosine. Increasing beta-alanine through supplementation may raise carnosine levels by over 60 percent in as quickly as four weeks.[6]
There have been a few reported renal health disorders associated with creatine supplementation [73,74]. These are isolated reports in which recommended dosages are not followed or there is a history of previous health complaints, such as renal disease or those taking nephrotoxic medication aggravated by creatine supplementation [73]. Specific studies into creatine supplementation, renal function and/or safety conclude that although creatine does slightly raise creatinine levels there is no progressive effect to cause negative consequences to renal function and health in already healthy individuals when proper dosage recommendations are followed [73-77]. Urinary methylamine and formaldehyde have been shown to increase due to creatine supplementation of 20 g/d; this however did not bring the production outside of normal healthy range and did not impact on kidney function [56,78]. It has been advised that further research be carried out into the effects of creatine supplementation and health in the elderly and adolescent [73,75]. More recently, a randomized, double blind, 6 month resistance exercise and supplementation intervention [79] was performed on elderly men and women (age >65 years) in which subjects were assigned to either a supplement or placebo group. The supplement group was given 5 g CM, 2 g dextrose and 6 g conjugated linoleic acid/d, whilst the placebo group consumed 7 g dextrose and 6 g safflower oil/d. CM administration showed significantly greater effects to improve muscular endurance, isokinetic knee extension strength, fat free mass and to reduce fat mass compared to placebo. Furthermore the supplement group had an increase in serum creatinine but not creatinine clearance suggesting no negative effect on renal function.
Creatine supplementation has once been noted to improve wellbeing and fatigue resistance in people with DM2, but has twice failed for people with DM1. In all three studies, it has failed to improve power output. This is thought to be due to a reduction in the expression of the creatine transporter preventing an increase in muscular phosphocreatine content.
Retinol (Vitamin A) B vitamins: Thiamine (B1) Riboflavin (B2) Niacin (B3) Pantothenic acid (B5) Pyridoxine (B6) Biotin (B7) Folic acid (B9) Cyanocobalamin (B12) Ascorbic acid (Vitamin C) Ergocalciferol and Cholecalciferol (Vitamin D) Tocopherol (Vitamin E) Naphthoquinone (Vitamin K) Calcium Choline Chromium Cobalt Copper Fluorine Iodine Iron Magnesium Manganese Molybdenum Phosphorus Potassium Selenium Sodium Sulfur Zinc

Some of these athletes take it to an unhealthy — and in some cases illegal — extreme with anabolic steroids, prohormones, diuretics, and potentially harmful substances. In addition to their potential performance-enhancing attributes, many of these substances also can have serious and significant side effects. A telling example of this is the story of ephedra — a once widely-used supplement for bodybuilding that has since been banned and removed from the market due to multiple reports of life-threatening side effects and death after its use.
That being said, men aren’t the only ones who suffer from low testosterone levels. Women can also suffer from testosterone deficiency which can affect their overall well-being in addition to their sex drive. If you’re a woman or man concerned about your testosterone levels, in addition to using supplements like the ones below, you should contact your doctor who will be able to diagnose any deficiencies and recommend additional treatments.
Heath suggests incorporating dropsets into your training routine by immediately decreasing the weight and repping out again to failure. “Dropsets overload the muscle with shorter rest periods and increasing volume which you need to grow,” says Heath. “That overload improves your body’s abilities to utilize more nutrients, natural growth hormone, and natural testosterone into those areas and makes the supplements you take more effective.” Heath’s favorite way to do dropsets is on a pin-loaded machine since it’s faster to switch weights. 

After all, if you’re doing more reps in a set, the weight would obviously be lighter and the intensity level lower. If you’re doing fewer reps in a set, the weight is obviously heavier and the intensity is higher. In addition, how close you come to reaching failure – aka the point in a set when you are unable to complete a rep – also plays a role here.
You may be wondering what conditions and medications contraindicate the use of creatine supplements. Creatine is contraindicated in people with kidney insufficiency or kidney disease. If you take diabetes medication, diuretics or acetaminophen, do not take a creatine supplement. Use caution if you regularly consume caffeine while taking a creatine supplement. Overall, if you are healthy and have gotten clearance from your doctor, consider this non-GMO creatine supplement.
Parashos, S. A., Swearingen, C. J., Biglan, K. M., Bodis-Wollner, I., Liang, G. S., Ross, G. W., Tilley, B. C., and Shulman, L. M. Determinants of the timing of symptomatic treatment in early Parkinson disease: The National Institutes of Health Exploratory Trials in Parkinson Disease (NET-PD) Experience. Arch Neurol. 2009;66:1099-1104. View abstract.

Creatine supplementation in the under 18 population has not received a great deal of attention, especially in regards to sports/exercise performance. Despite this, creatine is being supplemented in young, <18 years old, athletes [52,53]. In a 2001 report [52] conducted on pupils from middle and high school (aged 10 – 18) in Westchester County (USA) 62 of the 1103 pupils surveyed were using creatine. The authors found this concerning for 2 main reasons: firstly, the safety of creatine supplementation is not established for this age group and is therefore not recommended. Secondly, it was speculated that taking creatine would lead on to more dangerous performance enhancing products such as anabolic steroids. It is important to point out that this potential escalation is speculation. Furthermore, a questionnaire was used to determine creatine use amongst this age group and does not necessarily reflect the truth.
Most people require around 20 calories per pound (or 44 kcal / kg) of bodyweight to gain muscle mass. Using a 180-pound (82kg) male as an example, the required daily calorie intake is 3600 calories (20 kcal x 180 lb = 3600 kcal). When it comes to gaining weight, it is likely that you may put on a few pounds of fat along the way, but if you do find your body fat increasing, either increase the amount of aerobic exercise (moderate intensity) you are doing or slightly reduce the total number of calories you are consuming. Remember you can’t force feed muscle gain!
The 100% Grass-Fed Whey Protein Isolate comes in the form of powder and can be mixed with any liquid. While the protein powder can be mixed well with water, try mixing it with milk for added calories and protein. You can even add this to smoothies and baked goods to increase the protein profile. Recommended protein intake for adults is 0.8 grams per kilogram. Some athletes may need as much as 1.2-2 grams protein per kilogram. For your specific needs, always consult a registered dietitian.
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.
Some bodybuilders use drugs such as anabolic steroids and precursor substances such as prohormones to increase muscle hypertrophy. Anabolic steroids cause hypertrophy of both types (I and II) of muscle fibers, likely caused by an increased synthesis of muscle proteins. They also provoke undesired side effects including hepatotoxicity, gynecomastia, acne, the early onset of male pattern baldness and a decline in the body's own testosterone production, which can cause testicular atrophy.[42][43][44] Other performance-enhancing substances used by competitive bodybuilders include human growth hormone (HGH), which can cause acromegaly.

It’s important to remember that since everybody is different, these estimates are just that. How the numbers work out for each person will definitely vary. So many factors—like genetics, hormones, sleep, and diet—can change the rate at which our bodies burn calories. And some people may have a harder time than others when it comes losing fat or gaining muscle—again, there are so many factors at play and our body chemistries are all different. Strength training is important for many, many, many other reasons (more on that later), but if you’re looking to increase your metabolism, it’s important to have realistic expectations and know that strength training can make a difference, but probably won’t drastically affect how many calories you burn from one day to the next.
What happened was that, statistically speaking (less than 5% chance what was observed was due to chance means ‘significant’ for this study) there was no significant difference between pre- and post- workout, meaning that both were equally effective. This protocol did note that both groups found benefits with creatine supplementation, but they both found the same amount of benefit.
Contrast loading is the alternation of heavy and light loads. Considered as sets, the heavy load is performed at about 85-95% 1 repetition max; the light load should be considerably lighter at about 30-60% 1RM. Both sets should be performed fast with the lighter set being performed as fast as possible. The joints should not be locked as this inhibits muscle fibre recruitment and reduces the speed at which the exercise can be performed. The lighter set may be a loaded plyometric exercise such as loaded squat jumps or jumps with a trap bar.

Some people do have allergies to soy, or they have an intolerance to soy. If you notice certain symptoms (like a headache) after soy consumption, you may have an intolerance. Discovering your food intolerances/allergies would also be handled by a Dietitian. For the general population who are not allergic/intolerant to soy, however, soy-based products can be a part of a healthy diet. New research has shown that soy is not harmful as people fear. If soy gives you issues, you could always opt for whey protein, pea protein or other forms of vegetable protein. Have you seen our article on protein powders? Click here.
Isometric exercise provides a maximum amount of resistance based on the force output of the muscle, or muscles pitted against one another. This maximum force maximally strengthens the muscles over all of the joint angles at which the isometric exercise occurs. By comparison, weight training also strengthens the muscle throughout the range of motion the joint is trained in, but only maximally at one angle, causing a lesser increase in physical strength at other angles from the initial through terminating joint angle as compared with isometric exercise. In addition, the risk of injury from weights used in weight training is greater than with isometric exercise (no weights), and the risk of asymmetric training is also greater than with isometric exercise of identical opposing muscles.
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.
de Salles Painelli V, Alves VT, Ugrinowitsch C, et al. Creatine supplementation prevents acute strength loss induced by concurrent exercise. Eur J Appl Physiol 2014;114(8):1749-55.del Favero S, Roschel H, Artioli G, et al. Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids 2012;42(6):2299-305. View abstract.
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).[545]
Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects.[26] Clinically, there are three distinct disorders of creatine metabolism. Deficiencies in the two synthesis enzymes can cause L-arginine:glycine amidinotransferase deficiency caused by variants in GATM and guanidinoacetate methyltransferase deficiency, caused by variants in GAMT. Both biosynthetic defects are inherited in an autosomal recessive manner. A third defect, creatine transporter defect, is caused by mutations in SLC6A8 and inherited in a X-linked manner. This condition is related to the transport of creatine into the brain.[27] 
×