Syrotuik and Bell [57] investigated the physical characteristics of responder and non-responder subjects to creatine supplementation in recreationally resistance trained men with no history of CM usage. The supplement group was asked to ingest a loading dosage of 0.3 g/kg/d for 5 days. The physiological characteristics of responders were classified using Greenhaff et al [58] criterion of >20 mmol/kg dry weight increase in total intramuscular creatine and phosphocreatine and non responders as <10 mmol/kg dry weight increase, a third group labeled quasi responders were also used to classify participants who fell in between the previously mentioned groups (10-20 mmol/kg dry weight). Overall, the supplemented group showed a mean increase in total resting muscle creatine and phosphocreatine of 14.5% (from 111.12 ± 8.87 mmol/kg dry weight to 127.30 ± 9.69 mmol/kg dry weight) whilst the placebo group remained relatively unaffected (from 115.70 ± 14.99 mmol/kg dry weight to 111.74 ± 12.95 mmol/kg dry weight). However when looking at individual cases from the creatine group the results showed a variance in response. From the 11 males in the supplemented group, 3 participants were responders (mean increase of 29.5 mmol/kg dry weight or 27%), 5 quasi responders (mean increase of 14.9 mmol/kg dry weight or 13.6%) and 3 non-responders (mean increase of 5.1 mmol/kg dry weight or 4.8%). Using muscle biopsies of the vastus lateralis, a descending trend for groups and mean percentage fiber type was observed. Responders showed the greatest percentage of type II fibers followed by quasi responders and non-responders. The responder and quasi responder groups had an initial larger cross sectional area for type I, type IIa and type IIx fibers. The responder group also had the greatest mean increase in the cross sectional area of all the muscle fiber types measured (type I, type IIa and type IIx increased 320, 971 and 840 μm2 respectively) and non-responders the least (type I, type IIa and type IIx increased 60, 46 and 78 μm2 respectively). There was evidence of a descending trend for responders to have the highest percentage of type II fibers; furthermore, responders and quasi responders possessed the largest initial cross sectional area of type I, IIa and IIx fibers. Responders were seen to have the lowest initial levels of creatine and phosphocreatine. This has also been observed in a previous study [17] which found that subjects whose creatine levels were around 150 mmol/Kg dry mass did not have any increments in their creatine saturation due to creatine supplementation, neither did they experience any increases of creatine uptake, phosphocreatine resynthesis and performance. This would indicate a limit maximum size of the creatine pool.
Lung disease (Chronic obstructive pulmonary disease). Early research on the effects of creatine in people with chronic obstructive pulmonary disease (COPD) is inconsistent. Some research suggests that taking creating daily does not improve lung function. However, other research suggests that taking creatine may improve lung function or exercise capacity.

There is a nuclear receptor known as TIS1 (orphan receptor, since there are no known endogeouns targets at this time) which positively influences transcription of new creatine transporters[171] and, in C2C12 myotubes, seems to be responsive to cAMP or adenyl cyclase stimulation from forskolin (from Coleus Forskohlii) with peak activation at 20µM.[171][172] 
Some other cytokines and hormones may increase the receptor activity. These include growth hormone (GH) which acts upon the growth hormone receptor (GHR)[166][167] to stimulate c-Src[168][169] which directly increases the activity of the CrT via phosphorylation. This is known to occur with the 55kDa version of c-Src but not the 70kDa version and requires CD59 alongside c-Src.[170]
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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.
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.[104][105] When fed to chickens, phosphorylated cyclocreatine can accumulate up to 60mM in skeletal muscle,[106] which suggests a sequestering of phosphate groups before equilibrium is reached.[105] 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.[102]
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.

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,[560] this study failed to find an influence on activities of daily living or lung function.[560] Elsewhere in children not on corticosteroids with DMD, supplementation of 5g creatine for eight weeks was confirmed to increase muscular phosphocreatine content[554] 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%).[554]
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.[104][105] When fed to chickens, phosphorylated cyclocreatine can accumulate up to 60mM in skeletal muscle,[106] which suggests a sequestering of phosphate groups before equilibrium is reached.[105] 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.[102]
Creatine non-response is when muscular loading of creatine is under a certain threshold (10mmol/L), while “response” to creatine means having more muscular creatine loading (20mol/L or more). There also exists a “grey area” inbetween, where some benefits are achieved but not as many as pure responders will experience. Response appears to be positively correlated with muscle mass and type II muscle fibers.
A thermogenic is a broad term for any supplement that the manufacturer claims will cause thermogenesis, resulting in increased body temperature, increased metabolic rate, and consequently an increased rate in the burning of body fat and weight loss. Until 2004 almost every product found in this supplement category comprised the "ECA stack": ephedrine, caffeine and aspirin. However, on February 6, 2004 the Food and Drug Administration (FDA) banned the sale of ephedra and its alkaloid, ephedrine, for use in weight loss formulas. Several manufacturers replaced the ephedra component of the "ECA" stack with bitter orange or citrus aurantium (containing synephrine) instead of the ephedrine.
Antioxidants in the diet protect against natural and synthetic chemical fragments called free radicals that are a part of daily living. Lifestyle challenges may increase your requirements for antioxidants. Vitamin C and E are the main antioxidants in the normal diet although many other plant nutrients contribute to this effect. Pollution, stress, smoking, strenuous exercise, and illness may increase your requirements for antioxidant protection.
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.

More specifically, you can expect to end up in the upper half of these ranges ONLY if you are a beginner, younger, and/or have amazing genetics. You can expect to end up in the lower half of these ranges if you are an intermediate or advanced trainee, older, and/or have poor genetics. The average person can expect to end up somewhere in the middle. Additional details here: How Much Muscle Can You Gain?

If you are doing this on your own, but are overwhelmed and confused about strength training, I know how that feels. It can be scary enough to keep MOST people from starting, which is actually why we created our 1-on-1 Coaching Program. Our coach gets to know you, builds a program based on your experience and goals, will check your form on each movement (via video), and keep you accountable and on track!
So it was popular then, but is it effective now? Just because something is popular doesn’t mean it works. In the case of creatine supplementation, however, you can be confident that increased muscle strength and less fatigue is possible. All thanks to a critical chemical reaction taking place in your muscle cells. Read on and learn how creatine works and why it lives up to that nostalgic ‘90s hype.

Tough workouts drive muscle growth, but they generally cause a lot of damage to your muscles to do so. This damage often results in soreness for several days, which can make it tough to get to the gym or sometimes even move. Many bodybuilding supplements contain ingredients that work to reduce the breakdown of muscle during workouts, making the recovery process easier on the body.
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.
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]

The creatine transporter is a sodium[139][140] and chloride[141][142] dependent membrane-associated transporter that belongs to the Na+/Cl-dependent family of neurotransmitter transporters.[143] In muscle cells and most other cell types,[131][141] the isomer of the creatine transporter is known as SLC6A8 (solute carrier family 6, member 8). SLC6A8 is encoded by the gene present on the Xq28 region of the human X-chromosome and is expressed in most tissues.[144] A related gene encoding a creatine transporter variant has also been identified at 16p11.1 that is expressed exclusively in the testes.[145] These two transporters share 98% homology.[144][145]
K. Aleisha Fetters, M.S., C.S.C.S., is a Chicago-based personal and online trainer. She has a graduate degree in health and science reporting from the Medill School of Journalism at Northwestern University and regularly contributes to Men's Health, Women's Health,, TIME, and SHAPE. When she's not lifting something heavy, she's usually guzzling coffee and writing about the health benefits of doing so.
I’m glad you found some good information from this article. For any of these supplements, I would suggest talking to your doctor and pharmacist. I would suggest thinking about why you are interested in taking testosterone. Are you looking to increase muscle size? Bulk up? Knowing your fitness goals will help you determine which products are appropriate for you.
Health-food stores sell creatine supplements in capsule, chewable, and powdered form, the most popular being the powder. One teaspoon of powder contains 5 grams (g) of creatine monohydrate. The recommended daily dose is 1-2 teaspoons dissolved in 8 ounces of water or sweetened beverage. Manufacturers and distributors suggest a five- to seven-day loading phase with intake of 10-20 g (2-4 scoops) daily to fill up the muscle. The maintenance phase of 5-10 g/day is recommended before and/or immediately following a workout. This protocol is claimed to increase creatine muscle stores by 20-50%.
The majority of studies focusing on creatine supplementation report an increase in the body’s’ creatine pool [15-17]. There is a positive relationship between muscle creatine uptake and exercise performance [17]. Volek et al [18] observed a significant increase in strength performance after 12 weeks creatine supplementation with a concurrent periodized heavy resistance training protocol. The creatine supplementation protocol consisted of a weeklong loading period of 25 g/d followed by a 5 g maintenance dose for the remainder of the training. These positive effects were attributed to an increased total creatine pool resulting in more rapid adenosine triphosphate (ATP) regeneration between resistance training sets allowing athletes to maintain a higher training intensity and improve the quality of the workouts along the entire training period.
Homocysteine is an endogenous metabolite involved in methylation processes in the body. Mildly elevated homocysteine appears to be an independent risk factor for both cardiovascular[302] and atherosclerotic disease,[303] where if the 8-10μM normal range is elevated by around 5μM, it is thought to confer 60-80% greater risk of atherosclerotic disease[303]. Although it may not independently cause problems,[304] it may play a causative role in the context of the whole body system, since it is atherogenic by augmenting LDL oxidation[305] and promoting conversion of macrophages into foam cells.[306]
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.[147][148] The 73kDa band has been reported to be the predominant band in humans, with no differences based on gender.[148] 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.[149]

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.

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.