Caffeine, most of us have some form of it during the day, whether it is to enhance performance, or just because you like the taste.

But how much do you actually know about caffeine?

Considering that a staggering 80% of the world's population consume caffeine on a daily basis, and therefore it is easily the most popular drug in the world, caffeine is something we seemingly take for granted. Sticking the kettle on is a part of everyone's daily routine. It is also increasingly popular (especially in young children!) and readily available, everywhere you look these days there is a source of caffeine.

Its actual name is 1,3,7 trimethylxanthine and for something with such a long chemical name, the body can absorb it into the bloodstream very quickly (about 30-45 minutes). Meaning you can enjoy its effects quickly, without delay. There are not many other supplements that can legally improve your performance that quickly!

So, surely with caffeine being sold by large companies selling millions of cups a day, its fine and it is a perfectly healthy thing to consume. Right?

How does it effect you?

Probably the first thing people would say about caffeine is that they are addicted to it. That you NEED it to get through your day, otherwise you would fall apart, and not be able to function at your best, whether it be in the office or at a training session. This is somewhat of a fallacy, certainly when it comes to biological functioning.

The research suggests that when you crave for a caffeine hit, it is your body trying to tell you that it is water you require, and the craving is a learned behaviour, where drinking is associated with drinking caffeinated drinks instead of water. (Dr Batmanghelidj 1992).  So, according to this research you are not addicted to it, more than likely it's probably the social thing that we enjoy. Other research suggests that going cold turkey with caffeine will cause withdrawal symptoms, and this may well be more of a psychological effect rather than biological, and certainly other variables such as genetics, gender, personality and behavioural conditioning are going to contribute massively. This can also be true of hunger, therefore it seems that thirst is a crafty bugger, that often disguises itself so you can't do anything about it. Until it's too late!

OK, what proven biological negative effects does caffeine actually have on the body?

• Caffeine reduces the hormone melatonin, which is required for a restful deep sleep.

• In women, caffeine can contribute to a newborn having a low weight at birth.

• It can decrease memory enzymes, leading to short term memory loss.

• It can contribute to DNA damage.

• May cause or worsen attention problems and effect overall brain function in the longer term.

• Combined with artificial sweeteners, caffeinated drinks may combine the negative effects of caffeine with the negative effects of chemical sweeteners for a combo effect.

• Constant high caffeine ingestion may cause adrenal fatigue leading to chronic fatigue.

And the positive effects?

• It stimulates the central nervous system, which

• Increases alertness and concentration.

• It can increase aerobic performance as indicated by research which demonstrates that a 1500m run can be improvesd by around 4.2secs when 'under the influence' of caffeine (Wiles et al.,1992). As well as long term endurance performance (Costil et al., 1977; Costil et al., 1978; Ivy, 1979; McNaughton, 1987). The improved endurance performance is due primarily to a significant increase in the level of free fatty acids in blood plasma (Bucci, 1993). The increased levels of free fatty acids in the blood would enhance the ability to use said free fatty acids as a fuel, and therefore saves the use of valuable carbohydrate stores.  It should be noted that greater benefits are achieved if you are caffeine naive (Spriet, 1995). It has not been proved conclusively that a cup of coffee can improve strength, but there is some interesting research being done in this area, that may come to light in the near future.

• Contains antioxidants which can help your heart health.

• Can abort asthma attacks by relaxing the bronchial muscles.

• It increases the production of digestive acids, and can relax blood vessel muscles.

So, does caffeine cause dehydration? And what does dehydration mean anyway?

Dehydration is difficult to define exactly because of the various effects of intake and outlay of water (in drink/sweat/urine etc), but a good indicator of dehydration is a rapid loss of weight, greater than 3% of total bodyweight. I am certain that people competing in sports/events will have suffered dehydration at some point, and weighing the individual pre and post event (as all pro sports players do these days) is the easiest way to achieve this.

It is also difficult to advise people on the amount of fluid you should consume; we have all heard the "8 glasses of water per day" guide. It's a bit rough really, and will be vastly wrong for a professional athlete. A guide from a clinical standpoint is 35ml of fluid per kilogram of bodyweight (Harrison's principals of Internal medicine; Goodman & Gilman's: The Pharmacological Basis of Therapeutics). So if you weigh 120kg; that equals a daily intake of 4.2 litres of water. Just over double the 2 litres of fluid that 8 glasses gives you.

So, is the water you drink out of a tap is good enough, or do you prefer the expensive option of bottled water?

Matt Lovell, the highly regarded UK Sports Nutritionist is a massive advocate of water filtration (in particular reverse osmosis filtration as per picture below), to get rid of all the nasties that water companies put in the tap water these days. To find out more please visit here! He also has some great free info on sports nutrition and hydration, so sign up for his newsletter.

 

Caffeine and dehydration is also a question that has been in the press a lot recently, If you perform at the highest level, or just enjoy a bit of recreational fitness, you will have been told at one point or another "Don't drink too much caffeine prior to an event, it'll dehydrate you!"

Athleat wanted to see if this was true, you can't believe everything you read.

So, we are rolling out the Guinea Stig for his first official appearance in testing. I am sure it will be delighted that it's new high profile role with Athleat has it pissing in a cup, and sticking little bits of paper in it....

There are many forms of caffeinated beverages that are readily available, some with more caffeine than others. There are many more "thermogenic" products on the market from supplement companies with impressive names like Cytolean, Anabolic Shredabull and Muscletech Hydroxycut Hardcore. Certainly sounds like they would do the job!

But in the search for rapid fat loss, or just to kick start the day, are we jeopardising our health and athletic performance by being constantly dehydrated?

I suppose we need to start with accredited research, by proper scientists, who wear white coats, rather than our own resident rodent. So, the first place to start is with Dr. Ann Grandjean who is President of The Centre for Human Nutrition, Adjunct Associate Professor in Internal Medicine at the University of Nebraska Medical Centre, and a member of the University of Nebraska Graduate Faculty and the Interdepartmental Nutrition Program of the University of Nebraska-Lincoln. She also served as nutrition consultant to the University of Nebraska athletic department and the U.S. Olympic Committee. Well qualified enough for you?

The research article in question is by Dr Ann Grandjean (EdD, FACSM, CNS), hydration researcher and eminent sports nutritionist in association with the Institute of Medicine (IOM) and The Beverage Institute for Health and Wellness (BIHW). 

OK, enough with the abbreviations and posturing, lets strip this article right down to the bare bones......

In academic research, there can be negativity towards previously written articles, and this one is no different. The author of the current article seems pretty upset with the conditions the previous research was undertaken in (the research that led everybody to believe that caffeine dehydrated you).

The key difference between the two pieces of research is whether the subjects are being tested in real life caffeine consumption conditions. Our bodies develop a tolerance to most things if repeatedly exposed to them (our bodies are very good at making adjustments to maintain homeostasis), and caffeine has a lesser effect on the body after about three to five days of regular usage. This means that tests on subjects that have abstained from taking caffeine (called being caffeine naive) for a period of time prior to testing will skew the results markedly.

The study in question had 18 males consuming either water, or water plus varying caffeinated beverages (in a double blind placebo study), with their urine output measured, therefore working out their hydration status...The results of which showed no change. Simple.

So, if you regularly consume caffeine, it will contribute to your daily water intake because your body knows how to deal with it. If you do not drink caffeine on a regular basis, take lots of it prior to training or an event, it will act as a diuretic and contribute to you being dehydrated. Easy.

When Dr Grandjean was asked about pro athletes, and their increased need for fluids, and the effect of caffeine being heightened, she replied  "When water is consumed during the rehydration phase, a greater loss of electrolytes appears to occur than it does with caffeinated beverages. Moreover, in my experience working with professional and Olympic athletes, asking them to change their drinking habits by eliminating caffeinated beverages can lead to inadequate fluid consumption. They just won’t drink as much. In some cases, this can increase their risk of dehydration." So, caffeine is not the big bad wolf after all

So, what are the findings from the Guinea Stig? Completing an "at home" non-scientific experiment, the Guinea Stig followed a regimented 7 days, drinking a precise amount of water (in accordance with the recommended 35ml per kilo), with absolutely no caffeine, and measured his urine output whilst taking notes on colour and taking acidity readings at three set times during the day. Then it followed the exactly same regime whilst changing the caffeine intake to that of its normal daily routine (400mg), and drinking the same total amount of fluid but including its normal caffeine laden drinks into the equation.

The findings were reasonably conclusive considering the environmental conditions the test was undertaken in, but seeing as we could not restrict the Guinea Stig's training regime (because it needs to train as part of its job), meant we could not measure fluid loss through sweat and various other means, and therefore the results were not as concrete as we would have liked them to be.

What we can gather from this rodent research indicates similar results to that of Dr Grandjeans. The Guinea Stig was no more hydrated when in the grumpier non-caffeine phase than when he was sipping back on his favourite coffee. It is always satisfying to have results that match proper research!

 So, drink your espresso and your americano, but try and stay away from your calorie loaded latte, cappuccino and machiato, if you are a heavy coffee drinker, it could amount to a large amount of calories you did not account for in your daily calculations  (the average cup of coffee throughout the world has gone from 45 calories to 330 calories in the last 20 years.....a 63% increase!) Remember that when you are standing in the queue for your next coffee!

We hope this article has given you some insight into caffeine, and how you can use it to improve your athletic performance. Alongside great diet, hydration and a hard but effective and specific training regime caffeine can become a great ally. It has to used in the right way and in the right amounts to be truely effective, otherwise you could be wasting your time.

GOOD LUCK!

P.S Remember, the Guinea Stig is prepared to do anything in the pursuit of science, so email him at guinea-stig@athleat.co.uk if you fancy seeing him attempt something hard, stupid or ridiculous!

Please find below some of the reading undertaken whilst writing this article, it may be of no use to anybody, but it shows that we have at least done the research! Also see Eric Cressey and Brian St Clair's article - http://www.ericcressey.com/coffee-consumption-and-health-1

Selection of readings if you are keen!

1. Food and Nutrition Board of the Institute of Medicine. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate (2004).