2017/11/11 22:38:56
James Leave a comment

Glucuronolactone: A Pre-Workout Supplement Essential?

This article was originally published in The MuscleTalker August 2013 edition
Glucuronolactone (also known as D-Glucuronolactone, DGL, D-Glucurono-3,6-Lactone or D-Glucoronic Acid) is a key ingredient included in many popular stimulant energy and pre-workout drinks. It is a naturally occurring chemical produced from the metabolism of glucose in the liver and has been shown to increase endurance and improve reaction times at supplemental doses, making it an effective ergogenic stimulant and nootropic.

Stimulants like caffeine have vasoconstricting properties. Vasoconstriction is where the blood vessels narrow, increasing blood pressure and hotness which is one of the negative side effects from stimulant-containing drinks. One key ingredient in pre-workout formulas is nitric oxide - also known as arginine alpha-ketoglutarate (AAKG) - a vasodilator which helps give rise to those much sought after muscle pumps from a workout. Vasoconstrictor stimulants like caffeine cancel out some of the effects of AAKG, which is where glucuronolactone comes in: unlike other stimulants, it doesn't have any vasoconstricting properties. Thus it is often a preferred ingredient in stimulant drinks, like Red Bull as well as pre-workout drinks.

The exact effectiveness of glucuronolactone is unknown as previous research involves the study of energy drinks which also contain caffeine and taurine. It is therefore impossible to ascertain which compound was responsible for the enhanced benefits. However, there are a number of studies which demonstrate improved attention, reaction, speed and performance with the combination of glucuronolactone, caffeine and taurine.

Glucuronolactone is found in relatively small amounts, naturally. Red wine is perhaps the strongest natural source, with approximately 20mg of glucuronolactone per litre. Doses of as little as 0.5g have been shown to have an ergogenic effect, and doses of up to 1g are commonly found in supplements.

Glucuronolactone was said to be a carcinogen in larger amounts, but this has been dismissed as a rumour and debunked in the British Medical Journal and it is not restricted by the US FDA.
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2017/05/22 17:10:56
James Leave a comment

Energy Drinks

This article was written by Big Les & was originally published in The MuscleTalker April 2010 edition
For some people the very suggestion that energy drinks are a food will make their blood boil. With their popularity and proliferation (here in UK we don't have a tenth of the choice our US cousins get) has come media hype, knee jerk reactions and health nut jobs jumping on the band wagon. This month, food of the month sets out to give a balanced, rational picture.

In the UK the Energy Drink market is dominated by the big players, Red Bull, Monster, Rockstar, Relentless and the supermarkets own brands. Red Bull led the market, and has already seen itself embroiled in controversy enough to be banned in some countries (have a Google!). So what is in an energy drink? They are all at heart a combination of sugar and water, or if you are getting a low sugar version, water and sweeteners.

In addition to the base you will find a mix of 'energy boosting ingredients' including caffeine, taurine, B vitamins, ginseng, guarana and possibly some others depending on the brand. Guarana is a source of caffeine, so more of that in a moment. You may get 100% of your RDA of B vitamins from 500ml of energy drink, but unfortunately B vitamins will not boost your energy levels.

When it comes to vitamins the evidence is clear, 1) taking mega doses of vitamins does not boost performance, and may, in certain circumstances, even be harmful, and 2) taking vitamins only boosts anything if you were deficient in the first place.

Next up, ginseng. Ginseng varieties have been studied in relation to performance and the evidence has been in for a while. To have any effect you have to take ginseng consistently over time, and then the only effect that has been noted consistently is an increase in libido. Probably not the performance enhancement you were looking for!

Next taurine: once again we are going to be disappointed, taurine does not boost energy. In scientific studies taurine has shown promise in other areas, but not for athletes. And if that disappointment was not enough, over 2g a day has been lined to causing psoriasis in some people; it may not be confusion that has you scratching your head after all.

Finally caffeine: we know this well, the world's most popular drug. And, if you read the media hype, it is caffeine that has the potential to cause all of the problems put at the foot of the evil energy drink. So, a little perspective is needed. While the health Stasi have put energy drinks firmly in the firing line and the marketing machines have given the products some edge, the fact remains there is more caffeine in a 'Grande Americano' from Starbucks than there is in most 500ml cans of an energy drink.

So, let us sum up: energy drinks are a good source of caffeine, but they are apart from that no different from a can of coke (or diet coke of course), and as such, an athlete should treat them the same and give them the same place in their diet.
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2016/06/14 20:49:32
James Leave a comment

Nitric Oxide Pump Supplements

This article was originally published in The MuscleTalker November 2008 edition
Nitric oxide has definitely been one of the main supplement pre-workout trends over the past couple of years. Nitric oxide is the much touted 'pump' supplement used before training. It is often correctly abbreviated to NO; however many articles about this supplement wrongly abbreviate it to NO2, which is actually the chemical nitrogen dioxide, a poisonous air pollutant!

Many users try a new supplement with appropriate caution, as they've been stung far too many times before - haven't we all? The problem with gauging the usefulness of many supplements is that you need to be using the product for a while, and this means that other factors can affect gains and you can't easily deduce if it's the product working or the whole package of nutrition. The advantage that we have with pre-workout supplements, like nitric oxide, is that the effects are short term, so you'll either feel the difference or you won't during one workout. After a couple of training sessions you'll have your conclusion and be able to decide whether the product is worth continuing with. Without a doubt most people who use nitric oxide do feel the benefits, which is an enhanced muscle pump. A better pump, whilst doesn't actually directly mean more energy to train, does give both psychological benefits (the muscle feels good and you looked pumped therefore you train harder!) and means more blood is pumped to the muscle which will help recuperation and nutrition.

In mammals nitric oxide is a signalling molecule which is involved in physiological processes in the body like muscle contraction. It's a neurotransmitter which tells your blood vessels when to contract and relax. Nitric oxide signals for more blood to be pumped to organs when needed; when your arms need more blood supply for movement or for warmth, for example, the brain signals the blood vessels in the arms to release nitric oxide. After a large meal, nitric oxide sends more blood to your stomach to help you digest the food. It controls blood pressure, giving more blood when you exercise, and reducing the flow of blood when our body is at rest. Nitric oxide is also responsible for the relaxation of blood vessels in the penis, causing the blood to pool which produces an erection. Anti-impotence drugs like Viagra work in much the same way.

As a pre-workout supplement, nitric oxide can improve blood flow, oxygen delivery, glucose uptake, muscle velocity and muscle power over and above natural nitric oxide levels produced in the body. This gives the sensation of a full muscle 'pump' - that thing we strive for during a workout.
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2016/02/20 11:14:28
James 2 comments

What is Gakic?

This article was originally published in The MuscleTalker March 2007 edition
Gakic or, as it is scientifically known glycine-l-arginine-alpha-ketoisocaproic acid, first appeared on supplement shelves only two years ago, and now a number of well known supplement brands include it in their range. Some users claim it's the best thing since sliced bread... well since creatine, at least! But others are more sceptical as the evidence revolves around just two studies. On research it was noted that there was a performance benefit from taking three substrates in combination, i.e. glycine, arginine and alpha-ketoisocaproic acid (KIC), which when put together give us gakic.

Stevens et al (2000) demonstrated gakic supplementation significantly increased the total muscle work performed during intense sets of resistance training by an average of 10.5%, and it was shown to significantly increase fatigue resistance by up to 28% when compared with the placebo. This implied that you should be able to train harder and longer, thus helping you to achieve better results in strength and muscle size. This was followed up by another study in 2004 by Buford and Koch who demonstrated longer time to fatigue in gakic supplemented subjects compared to those on placebo.

So the observed benefits of gakic are there, but the problem with relying on the credibility of claims is that the mechanism by which gakic does this is not fully understood. One suggestion is by metabolic processes where gakic may aid in the removal of substances that build up during exercise, such as ammonia, which are involved in fatigue. Thus, if ammonia is cleared more quickly you can perform longer work, and push yourself harder than you normally would, i.e. you can train more intensely.

Those who are familiar with me will know of no bigger sceptic when it comes to supplements and outrageous claims. However, I will admit that both studies on gakic are of fairly good design and both indicate improved performance for muscular work. This leads me to believe that maybe gakic isn't another supplement fad, but could actually be a useful aid to exercise performance. However it is quite expensive and therefore there aren't a vast amount of people who have actually used it.

My conclusion therefore is the jury is still out on this supplement, in the delaying of fatigue and therefore improving performance. I'll not commit, but I do eagerly await more research.

Buford, B., and Koch, A. (2004). Medicine & Science in Sports & Exercise. 36(4):583.
Stevens, B., et al. (2000). Medicine & Science in Sports & Exercise. 32(12):2102
2016/01/20 15:03:46
James Leave a comment

Citrulline Malate

This article was written by former MT moderator MCL & was originally published in The MuscleTalker February 2006 edition
One supplement that has recently been introduced to bodybuilding is Citrulline Malate (CM). Studies in humans and rats have demonstrated that in those suffering from asthenia (muscle weakness), treatment with CM improves muscle performance. Treatment with CM has also been shown clinically to significantly improve recovery of physical activity following acute disease.

So how does CM exert these effects?
In subjects treated with CM compared with those untreated, following bicycle exercise the levels of ammonia and lactate in the blood of the CM treated subjects were much lower than the untreated subjects. This led to the finding that CM increases the rates of clearance of these substances from the blood. The actual mechanism for CM's action is not fully understood, but it has been shown that administration of CM leads to a greater production of ATP produced aerobically, and consequentially a lowered ATP production comes from anaerobic pathways. In simple terms, more energy is being produced by the aerobic pathway in your body, and so there is less lactic acid being produced and other such toxic by-products of anaerobic respiration, which lead to increased fatigue. Diet supplementation with CM hence is thought to increase the muscle's ability to be able to produce energy (ATP) aerobically.

So what advantage does this have for the bodybuilder?
Well I personally cannot see that there will be any significant differences noticed in any low repetition muscle building exercise, which rely little on aerobic pathways. If anything, CM supplementation might mean that lactic acid build-up is reduced thus meaning that nearer the end of one's weight training session, the user might be less fatigued than they would have been without CM, which may allow end of routine exercises to see improvements. However, I would see CM's main benefit to lie in the recovery of muscles - supplementing every day with CM can lead to increased recovery between sessions. In addition, for those who engage in more vigorous cardiovascular (CV) sessions, and those who are incorporating CV for fat loss, CM supplementation should be beneficial in allowing the user to perhaps increase the intensity of the CV performed, or increase the duration and recovery, which can be useful to those trying to use CV for fat loss.

An ideal dose to start with of CM would be around 6g per day, ideally split (3g in morning, 3g in evening or pre-workout). The user can increase the dose to 10g, or heavier users (over 200lb body weight) / non-responders may wish to increase further to around 12-15g. Typical duration for results to be noticed would be 7-14 days. This product does not need to be cycled, but it may be beneficial to do so, for example, 6 weeks on, 2 weeks off, etc. There is very little reported in the way of side effects. I recommend that CM be bought from a bulk powder supplier as this is the most cost effective way of purchasing CM.

In summary
CM can be a useful supplement for the athlete who is trying to increase their recovery between workout sessions, and an even better supplement for those wishing to reduce fatigue from CV sessions, allowing them to experience increased stamina and endurance.
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