Caffeine and Performance

Written by: Kevin Cann

            Caffeine and coffee consumption are always hot topics, whether it be for general consumption or athletic performance.  To understand if it can be a benefit in the diet we must first understand the mechanisms of action of caffeine.  The main course of action that our cup of coffee takes to stimulate us is by methylxanthine.

Methylxanthine is used in COPD treatment for its effects as a bronchodilator.  On top of stimulating our airways methylxanthine also increases heart rate and is an antagonist to adenosine receptors (Nehlig, 1992).  Adenosine is a neurotransmitter that causes us to become drowsy when it binds with its receptors due to the slowing of nerve cells.  Caffeine actually looks like adenosine to the receptors and will bind with them.  This disallows the adenosine to bind with those same receptors and make us drowsy (Ribiero, 2010).  Caffeine then increases neuron firing and this sends a signal to the brain that something is not right.  The pituitary gland is thus stimulated and releases the hormones responsible for our fight or flight response such as cortisol.  So what effect can this have on our health and performance?

For one, after we drink a cup of coffee we become less drowsy and more alert.  This can lead to increased productivity in the workplace.  One study actually proved that caffeine increases cognitive function.  This study measured the effects of 0, 12.5mg, 25mg, 50mg, and 100mg of caffeine on cognitive performance, mood, and thirst.  After receiving the dosage of caffeine the participants were then required to take two performance tests, a reaction test, and a rapid visual examination test.  All levels of caffeine had a positive effect on those tests, thirst, and mood (Smit, 2000).  Studies have also shown that caffeine may protect against the risk of Parkinson’s disease as well when consumed in moderation (Ascherio, 2001).

However, the release of our fight or flight response is also a stressor.  The dangers of being under a chronic stressor are well documented and include heart disease and cancer, among other illnesses.  One study showed a correlation with bipolar disorder and heavy caffeine consumption.  A case report showed a sudden drop of symptoms after 10 years of drug therapy, and removing heavy caffeine consumption seemed to be a major factor (Tondo, 1991).  Coffee may also increase our risk for coronary heart disease.  Studies on this topic are inconclusive, but the risk is definitely there, and coffee does raise our blood pressure.

Caffeine may or may not be beneficial to performance in sports as well.  Most studies are inconclusive and do not show that coffee consumption increases performance.  One study showed that doping with pure caffeine could allow an athlete to have a higher power output and workout longer (Graham, 2001).  I personally feel I get a better workout when I consume a cup of coffee approximately one hour before my exercise.  This may not be a direct effect from the caffeine, but may be due to the increased cognitive function and mood associated with caffeine consumption.  If I am more focused and I have a positive attitude I will definitely perform better than if I was drowsy and my mood was negatively affected.

In conclusion, we did not really answer our question whether we should be drinking caffeine or not.  As with many things in the world of nutrition the answer is: it all depends on the person.  If someone is free from excessive cortisol, adrenal fatigue, mental illness, and high blood pressure then a cup of coffee can be an enjoyable beverage drank in moderation that may even have some positive health benefits due to the antioxidants found in coffee.  If any of those conditions exist I recommend not taking in caffeine until those issues are in order.  If an athlete is looking for an edge in performance, maybe caffeine can alter focus and mood before a workout.  I have personally experienced a boost in performance with caffeine pre-workout. It may also benefit you to take it before a big test or an interview or meeting at work due to those shifts in positive mood and cognitive performance.  Tinker with coffee consumption and see how you react.






Graham, T.E. (2001).  Caffeine and exercise: Metabolism, endurance, and performance.  Sports Medicine.  Retrieved on March 5, 2012.

Tondo, Leonardo (1991).  The course of seasonal bipolar disorder influenced by caffeine.  Journal of Affective Disorders.  Retrieved on March 5, 2012.

Smit, HJ (2000).  Effects of low doses of caffeine on cognitive performance, mood, and thirst in low and high caffeine consumers.  Retrieved on March 5, 2012.

Ascherio, Alberto (2001).  Prospective study of caffeine consumption and risk of Parkinson’s disease in men and women.  Journal of American Neurological Association and Child Neurology Society.  Retrieved on March 5, 2012.

Nehlig, A (1992).  Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic, and psychostimulant effects.  Retrieved on March 5, 2012.

Ribiero, Joaquim (2010).  Caffeine and adenosine.  Journal of Alzyhmer’s Disease.  Retrieved on March 5, 2012.



Kevin is owner of Genetic Potential Nutrition. He is a holistic nutritionist, wellness coach, and strength coach. He works with people fighting illness, to competitive athletes. Check out his site at

Categories: General


Robb Wolf’s 30 Day Paleo Transformation

Have you heard about the Paleo diet and were curious about how to get started? Or maybe you’ve been trying Paleo for a while but have questions or aren’t sure what the right exercise program is for you? Or maybe you just want a 30-day meal plan and shopping list to make things easier? Then Robb Wolf’s 30 Day Paleo Transformation is for you.


  1. says

    Awesome write up. Love the fact that its not just me that has a cup of coffee 1 hour before exercise to get the most out of the session.

    Thanks, I will pass this around :)

  2. JRM says

    Genetic testing by 23andme said I was a slow metabolizer of caffeine. Should I be more inclined to avoid caffeine because of this?

    Is there some supplement that can speed up the metabolism of caffeine (like, the way that NAC helps the metabolism of alcohol)?

      • says

        Rob maybe an analagous MOA similar to mamalian canines having a hard time clearing theobromine (i.e. the whole ‘chocolate’ is a no no for dogs?). color me intrigued, i’d be way interested to know (too) if there is some subset of folks with a similar metabolic issue that makes them very sensitive to that class of compound.

  3. says

    Thanks for writing this post, Kevin.
    I concur, that I also have a better workout when I drink coffee about an hour prior (in addition, I do about EVERYTHING better with a cup of coffee :) )
    The problem I notice (just as you alluded to), is that coffee also makes my blood pressure rise dramatically (about 10-15 systolic points). Coupled with the natural rise in blood pressure while working out, I try to avoid coffee prior (Got to say here that I already am prone to high blood pressure if not vigiliant about it). Anyway, just as you said, I see both the benefits, and drawbacks of coffee consumption.
    Thanks for your great post.

  4. Ted says

    I’m a mountain bike racer. I raced semi-pro for several years, and pro, briefly. Personally, I’ve never noticed any effect from caffeine. But many of the people I raced against were popping No-Doze like they were Tic Tacs. A substantial majority has some kind of “special” coffee recipe, and they suck it down all morning. Some even go as far as to learn to tolerate warm, flat Coke, and fill their water bottles with it. (usually one with Coke, and one with Gatorade) I’ve heard that road bikers are about the same, except for the flat Coke.

    Again, it does nothing for me that I’ve ever noticed. But I can’t imagine all those people, at all those races, for all those years, wasting their time on something that’s useless. There’s something to it.

  5. says

    Totally agree with you. I think coffee is more than safe to drink and has some real performance inhancing benefits.
    However nowdays so many highly stressed people are consuming vast amounts of coffee and that is a lethal combo. Great write up. I love coffee but have just cut it out for 12weeks, 3 done an 9 to go.

  6. says

    Too many people use caffeine as a substitute for lack of sleep. Then the addictive nature of its use takes over. Also, some people, as mentioned, are far more sensitive and susceptible to its effects. My dh is one; it’s been a standing joke in our family about having to decaffinate dad a couple times a year. He’s a pilot, so works all hours. Typical pattern: gets off caffeine, his short temper disappears, he sleeps better, feels much less stressed, etc.; some months pass… Grouchy is waking up, Cranky is commenting, and I have the ah-ha moment–he is drinking caf-coffee again. It’s insidious, in part because coffee is on offer everywhere, so I’ll-just-have-one-cup sets in, then the self-perpetuating behavior resumes. He always feels better off the caffeine, but our culture promotes its use in a dozen ways. And, humans are past masters of rationalization! So, my take is, if you can’t have just one cup and stop there, it’s better to leave it alone.

  7. says

    neato write up man! you’ve inspired me to revisit the proposed MOA as I may have been operatingw with a ‘dated’ understanding , my understanding was that caffeine (or xanthines in general) worked more as cAMP phosphodiestrase inhibitors and thus kept that cool little nucleic acid secondary messenger hanging around longer so the actual signal that prompted the cascade (i.e. g protein mitigated beta adrenergic stimi )lasted longer or was ‘amplified’ in effect. perhaps it’s a combination and there is some of both happening? this would be way cool/interesting and make sense

    i do feel ,from past experience, that when I supplement with caffeine (either alone or as an adjunct i.e. with tyrosine, dmae, phenylalanine and or ephedrine) it definately gives me more pop than on it’s own and is usually more helpful for higher intensity ‘conditioning’ work , i dont find much measurable performance enhancement for general strength work i.e. gymnastics skill work, slow heavy lifting/powerlifts or accessroy training.

    so in addition to the important conditions you mentiond should be met, i.e. lifestyle factors you mentioned one should self screen for, do you guys see in your practices more benefit based on what type of training one is engaging in ? (i.e. more benefit for neuro heavy based work like oly lifts or higher intensity sessions in general ? )

    thanks for all the great info and updating you all (the whole team! ) do for everyone.

  8. Brian says

    I’ve cut back to a single cup of coffee a day, and try to have it prior to a morning workout. Can working out under the influence of coffee help to offset the cortisol production, or is this just adding more stress on top of the caffeine? I’ve looked around for information on the connection between coffee/caffeine and cortisol production, but haven’t had much luck. Trying to figure out if I would be better off eliminating the coffee completely, since I’ve got enough cortisol to begin with, or if I should only have a cup when I’m planning on working out and burning off the caffeine in a relatively short amount of time.

  9. paleoslayer says

    I fluctuate bw 2-4 shots of espresso daily. On some days (rest days) I take none- notice huge improvement in sleep quaLity.

  10. Jen says

    Ladies, caffein consumption is linked to fibrocystic breast syndrome. This is an uncomfortable inflammation some women experience at some point in their menstrual cycle or all the time and it can be rather severe. There is strong anecdotal evidence that avoiding caffein provides relief. I can personally attest to this. As far as I know the reason caffein has an effect is unknown.

  11. TMS71 says

    Keep in mind that many of the studies that show a positive effect of caffeine on performance are done on groups where caffeine users were not excluded. This horribly confounds the results because there is a slight degree of dependence on caffeine (slight compared to other drugs such as heroin) developed in habitual users. So when a study is done, in the 1st leg of the study the advise everyone to abstain from caffeine. For the habitual users you have withdrawal. Not surprisingly they perform poorly. Then for the 2nd leg of the study you administer caffeine to everyone and the habitual users have their fix and perform much better. Studies which have been done only on non-caffeine users have failed to show an improvement in performance.

  12. Baby says

    I have tried going off caffeine dozens of times and I have only made it, a week or so, on and off. Here is my question, to properly detox, and get the benefits that come when giving it up, how long does it take to shake that groggy feeling that I can’t seem to get through? If I knew there was 10 day window of groggy, or 2 weeks, maybe I could tough it out. Btw, I’m a new listener to the podcast and just discovered this website, love it!

  13. Jason_M says

    I LOVE coffee, but recently have switched to energy “shots” (Eternal Energy Shot) due to sensitivity to the acids in coffee and heartburn. I find the shots a little bit more convenient, so its a good alternative. Caffeine definitely has helped me make MASSIVE gains in resistance training, and that’s only been since recent use. Now I don’t workout without it.

Join the Discussion