Caffeinated Curiosity ~ Part One: Cognitive Awesomeness
November 23, 2014, Posted in Archives
If you would rather take caffeine supplements than drink coffee, Then we can’t be friends.
A little strong, but, coffee is great because it tastes great, but also because it is one a few reasons I survived my MSc research! Obviously it was not the taste alone that got me through this, it was the caffeine something I am sure we can all relate to.
Before we go any further, if you think coffee dehydrates you because of the caffeine content, then please listen to this podcast with Dr. Sophie Killer for information about why this rumour is not cool!
As the effect of caffeine is such a cluster-fu of awesomeness. It seems logical that we start by introducing caffeine and outlining the cognitive effects, before delineating how this relates to YOUR sporting performance in Part two. In Part three we then look at what the best strategies are to ingest caffeine? What amounts are required? Is there a difference in performance between coffee and caffeine supplements?
Most of us have it everyday ~ but what actually is Caffeine?
Caffeine is part of the methylxanthine family, which increases the excitability of the adenosine-sensitive sympathetic nervous system (Biaggioni et al, 1991; Kalmar & Cafarelli, 1999). These signals that originate within the sympathetic nervous system produce transient increases in the concentration of cyclic adenosine monophosphate (cAMP; Spraul et al, 1993).
cAMP is an intracellular (Canâ€™t pass through the plasma membrane) protein which regulates cell signal transduction (It basically controls processes in-side the cell such as ion transportation).
Caffeine inhibits the enzymatic degradation of cAMP by acting as an antagonist of adenosine, increasing the strength of transmitted signals (Dulloo et al, 2000; Belza et al, 2009). These general physiologic effects of caffeine are often presumed as stimulatory effectsâ€™ due to the perceived increases in concentration and feeling awake, however the beneficial response to caffeine intake is varied with many â€˜non-stimulatoryâ€™ effects also documented (Glade, 2010) â€“ But more on these in Part Two!
Check out this awesome photo which is a product of the Art of the Cell Blog by John Liebler – Check them out HERE
The yellow structures areÂ adenosine A2A receptors in the shell of theÂ nucleus accumbens of the brain. As we become tired, our bodies produce adenosine (the green small molecule above), which binds to these receptors and they, in turn, send signals to inhibit arousal. In other words, we get sleepy. Enter caffeine! (the orange small molecule above). Caffeine binds to the A2A receptors in place of adenosine and blocks the process, so we wake up.
Caffeine increases mental energy
Mental energy is an interesting term; everyone knows what it means but I am guessing few could tell you what it actually is (e.g. You eat carbohydrate for energy due to increases blood glucose. You drink coffee.). Cerebral blood flow (blood flow to the brain) has been documented as being proportional to acute caffeine intake (Addicott et al, 2009), with 400mg of caffeine significantly increasing blood flow through the anterior cerebral arteries (Sigmon et al, 2009) enhancing the efficiency of neuronal networks in the cerebral cortex (which plays a key role inÂ memory, attention,Â perceptual awareness and consciousness). A nice study demonstrated increases in neuronal activity in a network of brain areas that are associated with attention-demanding cognitive functions in tasks that required working memory (Koppelstaetter et al, 2008) after 100mg of acute caffeine ingestion. These increases in mental energy can enhance the functional capacity to engage in cognitively demanding tasks and are associated with increased vigilance, alertness and ability to concentrate (Lieberman, 2007) essentially meaning you are mentally prepped to DOMINATE!
Mental energy = > Cognitive Function = Sporting Performance
As previously mentionedâ€¦ caffeine makes you cognitively awesome. Several human studies have documented increased alertness, ability to concentrate, problem-solving ability, wake-fullness, and feelings of energy (Hogervorst et al, 2008; Hewlett & Smith, 2007; Hindmarch et al, 2000), with perceived effects documented in as little as 20 minutes (Hewlett & Smith, 2007; Lieberman et al, 1987) in varying doses and populations (Kennedy et al, 2008; Hindmarch et al, 2000). These benefits of caffeine extend beyond just reflections of enhanced mental energy, with associations documented between pre-exercise caffeine intake and post exercise accuracy/speed of performance in tests of complex cognitive function (Hogervorst et al, 2008), outlining importance of caffeine intake for sports which rely heavily on decision making. In many placebo-controlled studies, the placebo was ineffective, with the acute consumption of caffeine producing significant improvements in reaction time, accuracy of responses, ability to focus attention, ability to solve difficult problems, mental fatigue, and alertness (Rao et al, 2005; Lieberman et al, 1987). Caffeine’s relevance to enhance sporting performance is further supported by the acute consumption of a 64mg dose eliciting increases in the accuracy of response, coupled with decreases in reaction time (Lieberman et al, 1987), in healthy young adults: often the population of recreational and elite competitive physical activity.
Caffeine rocks… which is why a large proportion of the world are dependent on it. However remember that there is a habitual response; the magnitude of effect is proportional to how regularly and in what quantities you consume caffeine!
Now that the basics are locked down… Keep a look out for Part Two in the coming days to find out how to we can utilise caffeine intake to enhance your sporting performance!
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