Tag Archives: creatine

A Guide To Pre Workout Supplements




Pre-workout supplements, as the name suggests, are designed to be taken up to an hour before your workout and to provide a mental focus, physical strength and endurance boost. Most pre-workouts provide these performance boosting benefits through caffeine. It’s that simple. Lots of pre-workouts come loaded with specific amino acids, different sugars and all sorts of filler but in the end, the caffeine is the true source of any performance benefit.

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Caffeine is a well known stimulant, boosting mental clarity as well as physical endurance. If you are feeling sluggish after a long days work and struggle to bring energy to the gym, pre-workout supplements can remedy this and provide a powerful boost to all sorts of workouts from cardio to weight lifting.

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As always, don’t just take my word for it. Instead lets take a look at the science and studies which demonstrate the powerful performance enhancing effects of caffeine…

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What is caffeine?

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Caffeine is the most widely consumed psychoactive drug (one which alters brain function).  Most of this is in the form of coffee. Delicious coffee. I need a coffee. Caffeine fits into the methylxanthine class of molecules, home to a number of other stimulants. Caffeine is a well known CNS (central nervous system) stimulant which explains its powerful effects on perception, focus and co-ordination.

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Look at that sweet chemical structure

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Caffeine has a wide range of receptor, ion channel and enzyme targets beyond the scope of this article. Suffice to say, caffeine alters multiple physiological processes when consumed which explains its wide range of effects both cognitive and physical. The most important interaction to be aware of and one of the major ‘mechanisms of action’ is caffeine’s interaction with all sub types of the adenosine receptor (1).

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At these receptors, caffeine acts as an antagonist (it essentially stops them functioning for a short period of time). Whereas caffeine is a CNS stimulant, adenosine acts as an inhibitory neurotransmitter or a CNS depressant (2). By antagonising adenosine receptors, caffeine stops the depressing effects of adensoine.

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Caffeine antagonism of adenosine receptors  stimulates numerous brain nuclei that control (and increase) respiratory rate, heart rate and vasoconstriction (3). Simultaneously, this receptor antagonism also promotes the release of other neurotransmitters, like acetylcholine, which provides caffeine it’s stimulatory function.

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All of these are well documented responses to caffeine intake and underpin some of the numerous physiological changes that boost physical performance.

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We known HOW caffeine should boost performance but what evidence is there that caffeine supplementation actually benefits performance during cognitive or physical tasks.

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Fatigue and Drowsiness

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A number of studies have shown that caffeine reduces physical fatigue (4) and increases the time until fatigue is reached (5). Due to this, caffeine can be used as a temporary measure to prevent or treat ‘drowsiness’ (6). Drowsiness is described as a ‘state of strong desire for sleep’.

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Fatigue can apply to the weakening of muscle contractions over time or CNS fatigue in which the nervous system itself struggles to innervate the muscles, due to reduced neurotransmission. Caffeine appears to be better at alleviating muscle fatigue rather than CNS fatigue. CNS fatigue is a more serious condition usually resulting from prolonged over-exercise and inadequate nutrition.

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You so do you cute little bastard

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Due to these effects, caffeine can be used to prevent sleep (not encouraged) and can also increase task performance when sleep deprived (7). A heavily sleep deprived brain usually performs exceptionally badly in logic puzzles and tests of co-ordination.

Additionally, and without surprise, caffeine supplementation promotes increased focus and this results in better body co-ordination in general including hand eye co-ordination (8) – applicable to a number of sports.

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What about pre-workout use in the gym. Will it actually improve your performance?

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Caffeine and physical training

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Caffeine is a powerful molecule. Numerous studies (see above) have demonstrated its strong stimulatory effects on many aspects of physiology. The most relevant being wakefulness, focus, co-ordination and power output. Grouped together, these benefits are ideal for increasing performance in sports and lifting.

What does the science say regarding caffeine supplementation and exercise performance?

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Key message:

Caffeine increases performance in numerous forms of exercise both aerobic and anaerobic (9)

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Caffeine is a well established ERGOGENIC AID in humans (10). An ergogenic aid is a substance which provides a performance boost either mental or physical.  The performance enhancing effects of caffeine have been known for decades now and are highlighted in a number of older reviews (11,12)  In most measures of performance, those subjects taking caffeine out-performed their control counterparts.

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The general finding appears to be that the greatest difference in performance is seen 1 hour after caffeine intake.

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An array of studies have shown that caffeine is an effective performance aid in a number of sports/exercises. 

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Aerobic activities especially endurance sports (13)

Improved sprint performance (14)

Improved cycling performance and power output (15)

Anaerobic activities such as weight lifting (16)

Overall caffeine also delays the onset of muscle and central fatigue (17) which improves endurance across the board.

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As previously discussed, caffeine reduces fatigue and increases focus as well, all of which benefits exercises ranging from power lifting to endurance running.

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Of all the supplements explored on this website, pre-workouts will give you the most obvious and immediate boost in the gym due to the acute effects of caffeine stimulation.  Caffeine improves focus, endurance, co-ordination and performance in both anaerobic and aerobic exercises. A supplement for use in all fitness situations.


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Potential dangers

 

‘Pre workouts’ are, in theory, the most dangerous due to their high caffeine content. Always avoid these supplements if you are highly sensitive to caffeine. Never exceed the recommended dose stated by the manufacture.  As with creatine, I’d recommend cycling pre-workout use to give yourself a break every now and then. Be warned, that these supplements are POWERFUL. My own advice is to try half the recommended dose the first time you try it and adjust accordingly there after.

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Hahaha…but seriously…watch the dosage

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What about caffeine-free alternatives?

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Some people don’t handle caffeine as well as others. Instead of boosting mental clarity, individuals who are very sensitive to caffeine may find themselves ‘jittery’, experiencing involuntary shaking and restlessness. If you think or know you are sensitive to caffeine, supplementation with it is probably best avoided. The good news is that caffeine free pre-workouts do exist (or you can make your own using the list at the bottom of the article)

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Although caffeine is a huge part of the pre-workout formula, other components can boost your workout mainly by increasing endurance. These major additional components include beta alanine and citrulline malate both of which can be found detailed in the ‘On a tight budget’ section found at the bottom of the article.

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It can sometimes be hard to find to caffeine-free alternatives when using google as the vast majority are all caffeine based. To give you a head start I’ve listed the names of some of the most popular brands…

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  • EVOGEN EVP
  • MusclePharm VasoSport
  • MAN Pump Powder (What a name!)
  • NO explode (caffeine-free)

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The caffeine-free market was pretty sparse just a few years ago but the market is expanding year on year so the choice is growing larger than ever before. All 4 of these supplements have great user reviews and are considered some of the best. A good place to start if caffeine isn’t for you.

 


Top Picks

 

                                             

 

 

Both of these are great pre-workout products. NO explode is the cheaper option. It is also the first pre-workout I ever used and it blew me away. It tastes good and can fit into your budget at less than 20 GBP for half a kilo. It dissolves well. Most importantly it provides a meaningful boost in the gym, clearing your head and prepping your muscles for serious action.

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I’m a big fan of optimum nutrition as a supplement manufacturer in general and recommend their micro-ionzied creatine to give yourself a long term training boost. Their pre-workout maintains the high standards seen in other Optimum Nutrition products.

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On a tight budget?

 

Pre-workout supplements can be expensive but as with most supplements, the individual components are much cheaper than the final product. If you are working on a tight budget but still want to make the most of your gym sessions then you can make your own pre-workout formulas from home for a much cheaper price.

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All you will need are the major (non-filler) components found in most pre-workout brands.

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Caffeine: This stuff is cheap and comes powdered. A quick google will give you numerous options but the base product is the same. In terms of amount, try to match the caffeine content of reputable pre-workout products already on the market which have approximately 150 mg per serving.

Creatine Monohydrate: I’ve written extensively about the benefits of creatine for weight and power lifters. Creatine essentially acts as an additional energy store for muscle contractions. This allows you to squeeze out those important last repetitions when lifting weights. Pop about 5 g of this per serving in your pre workout.

Low or non-calorie flavouring of your choice

That sums up the basic mix. The caffeine is the key ingredient providing the performance boost. Don’t let anyone tell you otherwise!

If you are feeling fancy you can add some extra goodies on top…

Beta-Alanine: A couple of studies, explored in the link reviews,  have shown that beta-alanine can increase physical endurance allowing you to train for a longer period of time (18, 19). Aim for between 2 and 5 g per serving.

Citrulline Malate: In similar fashion, the amino acid L-Citrulline coupled to malate appears to boost performance in a limited number of studies (20,21). The most important aspect of this compound appears to be a reduction in fatigue, in theory allowing you to train for longer periods of time. Aim for around 3 g per serving.

Thanks for reading,

Any further questions or advice? Head to the comments section or email me directly at ed@scienceguysupplements.com

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References

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References can now be found linked directly in the text rather than listed in this section. Delving deeper into the research has never been easier!

If you are looking to do a bit of your own research, on any topic, PubMed and Google Scholar both have a huge literature collection.

The Best Workout Supplements

A collection of the very best workout supplements that can take your training to the next level. Supplements can be great for an extra edge in the gym whether your focus is weightlifting and muscle building or functional training and cardio.

Supplementation can also be fantastic for the seasoned athlete trying to break through a a plateau. Whether you need an energy boost or extra protein and calorie this is the ultimate list for you. Keep checking this page for future supplement additions with real scientific evidence supporting their use.

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Whey Protein

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Whey protein comes in multiple forms and is perhaps the single most widely sold fitness supplement today. Protein is essential for building muscle so if your goal is to hit the weights and get bigger and stronger, frequent use of whey protein can give you a much needed protein injection. I have written and extensive guide on whey protein so don’t forget to check it out! 

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Great for:

-Muscle building

-Workout recovery

-General weight gain

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The Top of the Pile:

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MyProtein Impact Whey is a firm favourite of mine and has been for years. This is a ‘whey isolate’ and has very high protein per serving with comparatively low fat and carbs

When I can afford it (!), I’ll treat myself to a tub of Optimum Nutrition Whey. This is ‘whey hydrosylate’ and the pinnacle of protein supplements. The idea with hydrosylates is that they have been pre-digested to help protein absorption. Go on, treat yourself.

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Mass-Gainers

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Mass gainers are all about high calorie intake. If you are serious about putting on general size then mass gainer shakes pack an absolute ton of calories. If you are already big and want to get bigger than you calorie demands will already be high. For some, eating 6,000 calories a day is difficult and requires careful meal preperation. If calories are missed for whatever reason, a mass gainer shake can pick up the slack. Using mass gainers can easily add over 1000 calories to you daily diet.

Evidence suggests that once our protein needs are met, increasing calories from non-protein sources is the best way to maximise muscle growth. Simply taking on more protein doesn’t seem to work. Mass gainers can therefore give you the edge.

Unlike whey isolates, mass gainers are full of carbs and fats as well as protein. If you are looking to stay lean and gain weight slowly then mass gainers probably aren’t for you. For anyone competing or training in strong men events or wanting to pack on general size, mass gainers are ideal.

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Great for:

-Fast weight gain

-Strongman or strength training

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The Top of the Pile:

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Both are great products. MyProtein Hard Gainer has more calories per serving than Serious Gainz but is noticeably more expensive. Both products contain high levels of protein, with a good level of carbohydrates and fats as well. Perfect for gaining weight which ever brand you choose.

 


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Creatine

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Essentially acting as an extra store of skeletal muscle energy, (phospho) creatine is especially useful for weight lifters. Creatine has been shown to increase maximal lifts as well as total rep number before muscle fatigue so is great for breaking through plateaus. Couple creatine with whey protein for a powerful weight and power building supplements. Check out my extensive creatine article for everything you could possibly want to know about this super popular supplement. 

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Great for:

-Muscle building

-Breaking training plateaus

-Strength training

-Increasing maximum lifts

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The Top of the Pile:

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MyProtein creatine monohydrate is a great all round creatine product. It’s cheap and does exactly what it says on the tin. One 500g bag only sets you back 7 pounds but can last you for months depending on usage. Especially during your first few uses, creatine has a very clear positive impact on your training and the strength increases are noticeable if used correctly with good training technique.

Optimum Nutrition Creatine is more expensive than other brands but for some this is completely worth it. As this creatine is ‘micro-ionsied’ it dissolves much better in any liquid so is much more pleasant to drink. Some brands don’t really dissolve at all so it can feel like you are drinking sand. If that sounds like an issue then grab a tub of Optimum Nutrition Creatine. Remember, aside from these small dissolving difference, the core supplement, and it’s benefits, are identical.

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Pre-Workouts

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Pre-workout supplements provide their major benefit through caffeine . Caffeine is a well known stimulant, boosting mental clarity as well as physical endurance. If you are feeling sluggish after a long days work and struggle to bring energy to the gym, pre workout supplements can remedy this and provide a powerful boost to all sorts of workouts from cardio to weight lifting. I’ve written an article telling you everything you need to know about caffeine, how it effects your physiology and how it can benefit you in training and exercise.

Of all supplements, ‘pre workouts’ are in theory the most dangerous due to their high caffeine content. Always avoid these supplements if you are highly sensitive to caffeine. Never exceed the recommended dose stated by the manufacture.  As with creatine, I’d recommend cycling pre-workout use to give yourself a break every now and then. Be warned, that these supplements are POWERFUL. My own advice is to try half the recommended dose the first time you try it and adjust accordingly there after.

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Great for:

-Smashing the weights: setting a new personal best lift

-Temporary endurance increase: good for cardio

-Fighting tiredness if training in the evening

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The Top of the Pile:

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Both of these pre-workout supplements are great products from reputable brands. Of all the supplements on this page, pre-workouts will give you the most obvious boost in the gym due to the acute effects of caffeine stimulation.  Caffeine improves focus, endurance, co-ordination and performance in both anaerobic and aerobic exercises. A supplement for use in all fitness situations.

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Don’t forget, these lists are frequently updated so check back for more approved products that actually work. If you have any specific questions, head to the comments section or alternatively feel free to reach me at ed@scienceguysupplements.com

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-ScienceGuy

 

The Science of Creatine

 

During my time in the gym I’ve overhead numerous talk of creatine being illegal, a steroid, a protein, an ab-specific weight loss aid (eh??)…The list is endless and almost everything I’ve overheard is incorrect. I thought it would be useful to provide a clear piece of information that tells you what creatine actually is, how it impacts you on a physiological level, exaggerated side effects and if it can aid in your training.

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Creatine is perhaps the most well researched supplement on the market today.  Initially, fairly ‘low-dose’ creatine supplements where the norm but specific creatine supplements designed specially for strength training where not developed until the mid 1990s. The first such product was named Phosphagen by a company called EAS (1). Since then creatine supplements have exploded in popularity.

 

 


 

WHAT IS CREATINE?

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Creatine is a nitrogenous organic acid that aids in generating energy for cells, the most immportant being muscle cells. Creatine is not an essential nutrient and is produced naturally by the body from the amino acids glycine and arginine (2). The biosynthesis reaction is pretty tastey:

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Nothing boring about that...
Nothing boring about that…

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Almost all of this reaction occurs in the kidneys and liver. The produced creatine is then transported to skeletal muscle where the vast majority of it remains (3). Studies suggest as much as 50% of stored creatine in the muscles comes from dietary sources, mainly red meats, and that vegetarians possess significantly less natural creatine in their muscles than meat eaters (4) but levels are equal when both groups supplement (Get supplementing you veggies!)

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PHYSIOLOGICAL ROLE

 

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The importance of creatine in the body is highlighted by genetic disorders which disrupt the biosynthetic pathway pictured above. The major genetic disorders are associated with the synthesis enzymes or disruption of creatine transport into the brain (5,6). The end result of any of these genetic abnormalities is severe neurological defects suggesting creatine plays an important role in normal brain function (7). Additionally, research has shown that creatine supplementation provides not only physical enhancement but also cognitive improvements as well (8).

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Now for the important part: What does creatine actually do when it is sitting in the skeletal muscle? First we need to understand the power of ATP.

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All cells in our body utilise an ‘energy currency’ called ATP (Adenosine TriPhosphate) which we ultimately produce from the food we eat in the form of glucose (9). When energy is required in a cell a phosphate ion is split from the ATP molecule which then becomes ADP (Adenosine DiPhosphate). The breakdown of the last covelant link between phosphate and ATP liberates energy which can be utilised by the cell for a number of processes including movement, growth or protein synthesis (10)(In our case we want that cell to grow some big-ass biceps).

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Creatine itself can be phosphorylated into phosphocreatine with the addition of a phopshate ion take from ATP (12). Phosphocreatine comes into play by essentially acting as a phosphate store for when energy demands are high. At some point during exercise ATP is being reduced to ADP faster than ADP is restored to ATP. Our total ATP concentration is falling and thus so is our available energy. In the muscle, phosphocreatine is stripped of its precious phosphate which is then attached to a wandering ADP molecule. This provides a fresh new ATP molecule to power a cellular process.

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That is how creatine works as a supplement in a nut shell. It acts as a store of potential energy. The idea behind supplementing with large amounts of creatine is that we increase the creatine concentration in our muscles thus providing a larger store of energy which should allow for greater numbers of muscle contractions before we fatigue.

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Phopshate + Creatine (requires ATP) = Phosphocreatine

Phosphocreatine + ADP = Creatine + ATP       

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HOW WILL THIS AID MY TRAINING – WHAT DOES THE RESEARCH SHOW?

 

Creatine supplementation, in theory, provides a greater store of utilisable energy to skeletal muscle. This allows greater use of that muscle before the onset of muscle fatigue. In reality creatine supplementation is great for some types of exercise and fairly poor or non beneficial for others. Creatine will be of most use in high intensity anaerobic repetitive work (13). This would include something like weightlifting in which a number of repetitions are performed and then a break is taken. This can also include high intensity workouts involving rapid sprinting/cycling (14). Modest improvements have also been seen in ‘single effort work’ for example, a one rep max on a very heavy weight (15). In this area creatine has been shown to increase general performance with a focus on maximum power.

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Areas where creatine will not help at all are mainly endurance based sports, for example, long distance running (16). Presumably this is due to the fact that muscle activity is maintained for a long period of time and a lack of rest reduces ATP replenishment rates (ADP–>ATP) even when high levels of creatine are present in the muscle.

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'Is this how you do a bench press?'
‘Is this how you do a bench press?’

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To briefly summarise a number of other studies…It has been demonstrated that subjects receiving creatine supplementation along with resistance training lead to decreased serum myostatin concentrations compared to subjects that trained with no creatine or subjects which didn’t train and also didn’t receive any creatine (17). (Really we should have another group here that took creatine without doing resistance training but hey ho). Myostatin is important for INHIBITING muscle growth so a lack of it should allow for greater muscle development. Ever seen a Belgian Blue cow? These guys have been selectively bred to lack functional myostatin….

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Look at dat ass...
MOO BITCH

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Additional studies performed on young college footballers have also shown modest increases in circulating dihydro testosterone as well as testosterone itself following creatine supplementation (18.19) (please follow the references for greater detail). Creatine may therefore enhance your training in multiple ways, not just providing additional ATP for muscle contractions.

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Take home message: Creatine has no significant effect on aerobic endurance. However, it will increase power during short, repetition-based exercises including weight lifting and high intensity cardio training.

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COMMERCIAL FORMS

 

drugs

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Creatine can be purchased as a powder or as a tablet. I have always personally gone with a non-flavoured powder as it is easy to add to a protein shake. Tablets may be more convenient for people who want to take their creatine at a specific time when not at home. In terms of performance, both forms contain the same product but powdered creatine may provide faster absorption into the system. Make sure to read the manufacturers instruction when switching to a new creatine and always stay within the recommended dose.

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Something of additional importance to point out is that the supplement industry in general is always looking for ‘the next big thing’ to sell you. Very often ‘new and improved’ versions of creatine will make their way onto the market with loudly advertised improvements such as malate or citrate. These newer products offer no advantages over standard creatine but usually cost considerably more. Stick with standard creatine monohydrate (the form on which most research is based) for the same functional product at a lower cost.

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HOW AND WHEN TO TAKE CREATINE

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Most users of creatine, and most creatine product labels, suggest a loading phase followed by a maintenance phase of creatine dosing. The idea here is to saturate yourself (mainly your muscles!) with high levels of creatine in the first week followed by a lower dosing from then on. This is what I personally do whenever I have taken a break from creatine i.e. when going abroad for a week or two with limited weight training.

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It is common to see a cycle suggested on the product label. for example

Week 1: LOADING 5g x 4 times daily

Week 2-8 MAINTENANCE 5g daily

BREAK (usually 1-4 weeks)

REPEAT PROCESS

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It is not necessary to cycle creatine at all as it can be taken for a long period of time with no ill effect to health. However, most people throughout the year have commitments that may reduce or entirely remove their ability to train and this can be an opportunity to take a break from creatine and re-load when returning to the gym.

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SIDE EFFECTS AND HEALTH ISSUES

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One of the major things you may hear about creatine is in regards to it safety as a long-term supplement. Modern creatine-based supplements have only been around for two decades. Research can therefore only address this far back. Some studies looking into the health impacts of long term creatine use have lasted as long as five years. In most cases this is ample time to uncover any safety-related issues.

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Commonly cited 'side-effects' of creatine use such as kidney and liver damage, muscle cramps and dehydration have been thoroughly debunked in the literature

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Kidneys: Common statements seem to be that long term creatine use may lead to kidney and/or liver damage. Kidney damage is the most widely cited issue. This is probably due to research being portrayed in a misleading manner. When additional creatine is taken into the body, creatine breakdown products, namely creatinine, will also increase in the blood as well as in the urine. Serum creatinine levels are commonly used as an indicator but not direct measure of kidney function. Therefore, when supplementing with creatine, do not be alarmed by a rise in creatinine levels. Multiple human studies have confirmed that longer term creatine use is not damaging to the renal or hepatic systems in any way (20, 21, 22).

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kidneys

 

 

 

Gastro-intestinal Tract: GIT disruption CAN occur with larger doses of creatine, especially when taken on an empty stomach. This is sometimes referred to as ‘Mud Butt’ in some gyms. GIT disturbances are very rare, short lasting and self-resolving. These mild GIT issues can be avoided by taking smaller doses more frequently or eating something before hand. If you decide to cycle creatine and are starting the ‘load phase’ avoid taking your daily creatine all at once. Instead try to split dosing across the day.

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Heat tolerance and muscle cramping: Internet rumours suggesting creatine messes with thermoregulation, induces dangerous dehydration and/or muscle cramps have now been thoroughly debunked in two systematic reviews on the topic (23, 24)

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Weight gain: This is something that I actually found to be true but the weight gain I observed was probably due to water being pulled into the skeletal muscles. A number of studies have shown an acute increase in water retention in muscles following creatine loading but this subsides and has no negative effects on your training or health. Ultimately creatine has been shown more than once to promote FAT LOSS and lean MUSCLE MASS GAIN due to higher training intensities and volume (25,26).

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To date, research has found no negative impact to kidney, liver, intestinal function or any other major organ for that matter.In fact, in rodent studies, creatine improved the life span of mice (27) but whether this translates to humans remains to be seen. If you are a healthy individual then creatine is perfectly safe to take over the  long term. However,  it is important to point out that if you have a PRE-EXISTING KIDNEY DISORDER then it is probably best to avoid creatine-based supplements in general unless your doctor says otherwise.

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Take home message: Creatine can provide a real benefit to your workouts if you lift weights or perform high intensity cardio workouts. The supplement is cheap and safe to to take over a long period of time. Creatine comes in multiple forms but the standard powdered creatine monohydrate is the most popular for a reason.

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TOP PICKS

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I’ve tried a few different creatine manufacturers before. It can be an overwhelming choice as there are quite literally hundreds of different brands. However, on the inside of the tub its all essentially the same. My Protein Creatine monohydrate is very cheap and does a good job. It doesn’t dissolve well but I add it to my whey protein so don’t notice when drinking it. This is the stuff I’m currently using. The ‘micro-ionised’ powder by Optimum Nutrition dissolves much better so may be a good choice if you plan on taking the creatine by itself with water or juice. Creatine monohydrate can also come ‘flavoured’ which makes the experience of drinking it much more pleasant if just using water. My Protein offers a number of flavours and is a good place to start.

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Thanks for reading and please feel free to comment about your experiences with creatine whether good or bad. You can also reach me at ed@scienceguysupplements.com

-ScienceGuy





 

REFERENCES

I recommend using Google Scholar for quick access to these studies.

 

(1) Stoppani, Jim (May 2004). Creatine new and improved: recent high-tech advances have made creatine even more powerful. Here’s how you can take full advantage of this super supplement. Muscle & Fitness.

(2) “Supplement muscles in on the market”. National Review of Medicine. 2004-07-30

(3) Passwater, Richard A. (2005). Creatine. p. 9

(4) Burke DG, Chilibeck PD, Parise G, Candow DG, Mahoney D, Tarnopolsky M; Chilibeck; Parise; Candow; Mahoney; Tarnopolsky (2003). “Effect of creatine and weight training on muscle creatine and performance in vegetarians”. Medicine and science in sports and exercise. 35(11): 1946–55.

(5) “L-Arginine:Glycine Amidinotransferase” http://omim.org/entry/602360

(6) Braissant, O; Henry, H; Béard, E; Uldry, J (May 2011). “Creatine deficiency syndromes and the importance of creatine synthesis in the brain.”. Amino Acids. 40 (5): 1315–24.

(7) Hemmer; W, Wallimann, T (1993) ”Functional aspects of creatine kinase in brain” Developmental Neuroscience. 15 (3-5): 249-260

(8) Rae, C; Digney A.L; McEwan S.R (June 2003). ”Oral creatin supplementation improves brain performance: a double blind, placebo controlled, cross-over trial”. Royal Society Publishing. 270, 2147–2150

(9) Knowles, J. R. (1980). “Enzyme-catalyzed phosphoryl transfer reactions”. Annu. Rev. Biochem. 49: 877–919.

(10) Campbell, Neil A.; Williamson, Brad; Heyden, Robin J. (2006). Biology: Exploring Life. Boston, MA: Pearson Prentice Hall.

(11) Di Carlo, S. E.; Collins, H. L. (June 1, 2001). “Submitting illuminations for review”. Adv. Physiol. Educ. 25 (2): 70–71

(12) Saks, Valdur (2007). Molecular system bioenergetics: energy for life. Weinheim: Wiley-VCH. p. 2.

(13) Bird, S. P. (2003). “Creatine Supplementation and Exercise Performance: A Brief Review” (PDF). Journal of Sports Science & Medicine. 2 (4): 123–132.

(14)  Graham, AS; Hatton, RC (1999). “Creatine: A review of efficacy and safety”. Journal of the American Pharmaceutical Association. 39 (6): 803–10; quiz 875–7.

(15)  Engelhardt, Martin; Neumann, Georg; Berbalk, Anneliese; Reuter, Iris (1998). “Creatine supplementation in endurance sports”. Medicine & Science in Sports & Exercise. 30 (7): 1123–1129

(16) Kreider R, Rasmussen C, Ransom J, Almada AL (1998). “Effects of creatine supplementation during training on the incidence of muscle cramping, injuries and GI distress”. Journal of Strength Conditioning Research. 12 (275).

(17)  Saremi, A.; Gharakhanloo, R.; Sharghi, S.; Gharaati, M.R.; Larijani, B.; Omidfar, K. (2010). “Effects of oral creatine and resistance training on serum myostatin and GASP-1”. Molecular and Cellular Endocrinology. 317 (1–2): 25–30

(18)  Van Der Merwe, Johann; Brooks, Naomi E; Myburgh, Kathryn H (2009). “Three Weeks of Creatine Monohydrate Supplementation Affects Dihydrotestosterone to Testosterone Ratio in College-Aged Rugby Players”. Clinical Journal of Sport Medicine. 19 (5): 399–404.

(19) Hoffman, J; Ratamess, N; Kang, J; Mangine, G; Faigenbaum, A; Stout, J (2006). “Effect of creatine and beta-alanine supplementation on performance and endocrine responses in strength/power athletes”. International journal of sport nutrition and exercise metabolism. 16 (4): 430–46.

(20) Kreider, Richard B.; Melton, Charles; Rasmussen, Christopher J.; Greenwood, Michael; Lancaster, Stacy; Cantler, Edward C.; Milnor, Pervis; Almada, Anthony L. (2003). “Long-term creatine supplementation does not significantly affect clinical markers of health in athletes”. Molecular and Cellular Biochemistry. 244 (1–2): 95–104.

(21) Mayhew, DL; Mayhew, JL; Ware, JS (2002). “Effects of long-term creatine supplementation on liver and kidney functions in American college football players”. International journal of sport nutrition and exercise metabolism. 12 (4): 453–60

(22) Gualano, Bruno; Ugrinowitsch, Carlos; Novaes, Rafael Batista; Artioli, Guilherme Gianini; Shimizu, Maria Heloisa; Seguro, Antonio Carlos; Harris, Roger Charles; Lancha, Antonio Herbert (2008). “Effects of creatine supplementation on renal function: A randomized, double-blind, placebo-controlled clinical trial”. European Journal of Applied Physiology. 103 (1): 33–40.

(23) Lopez RM, Casa DJ, McDermott BP, Ganio MS, Armstrong LE, Maresh CM; Casa; McDermott; Ganio; Armstrong; Maresh (2009). “Does Creatine Supplementation Hinder Exercise Heat Tolerance or Hydration Status? A Systematic Review With Meta-Analyses”. Journal of Athletic Training. 44 (2): 215–23.

(24) Dalbo VJ, Roberts MD, Stout JR, Kerksick CM; Roberts; Stout; Kerksick (July 2008). “Putting to rest the myth of creatine supplementation leading to muscle cramps and dehydration”. British Journal of Sports Medicine. 42 (7): 567–73

(25) Antonio J, Ciccone V. The effects of pre versus post workout supplementation of creatine monohydrate on body composition and strength. Journal of the International Society of Sports Nutrition. 2013;10(1):36.

(26) Becque MD, Lochmann JD, Melrose DR. Effects of oral creatine supplementation on muscular strength and body composition. Med Sci Sports Exerc. 2000;32(3):654-658.

(27) Bender, A.; Beckers, J.; Schneider, I.; Hölter, S.M.; Haack, T.; Ruthsatz, T.; Vogt-Weisenhorn, D.M.; Becker, L.; et al. (2008). “Creatine improves health and survival of mice”. Neurobiology of Aging. 29 (9): 1404–11