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Caffeine
The Effects of Caffeine on Recovery and Performance
In my last article, I stated the importance of giving your body a period of recovery from the process of recoveryitself. I suggested taking at least ten days off from any activity at some point over the fall or winter beforebeginning your training for new season. In addition to that, I suggested that if you were a coffee drinker, takinga break from your daily ingestion of caffeine would be also be helpful. I thought taking the time off the bikewas going to be challenging for many of you, but it turns out I received the most mail about coffee. Enough sothat I thought it warranted an article of its own.
The reason why it's important to try and lay off the coffee is of course the caffeine. When you're taking time offthe bike, as I said, the goal is to allow your body to completely heal. You want to give it a break from the stresson the hormonal systems, the releasing of adrenaline, testosterone production, HGH production, etc. Caffeine isa stimulant that affects the central nervous system, the importance of which has been written about many timeson Bike.com by coach Rick Crawford.
Caffeine in many ways is a wolf in sheep's clothing. It looks like adenosine to nerve cells in the brain, so thosecells welcome it with open arms. Adenosine is a chemical that binds to adenosine receptors and causesdrowsiness by slowing down nerve cell activity, helping with normal sleep patterns.
Caffeine behaves much differently than adenosine, and speeds the cell's activity up where adenosine would slowit down, putting the body into a state of alert. This increase in activity sets off a chain reaction in the body. Thepituitary gland reacts by releasing hormones that cause the adrenal gland to produce adrenaline. As a result,bronchial tubes dilate to increase breathing, heart rate increases, blood pressure rises, sugar is released into theblood stream, and your body generally prepares for action.
The problem is, most of us aren't preparing for action with our morning cup of coffee. We're simply trying towake up. But again, caffeine is a stimulant, and like most stimulants, it's addictive. The dose that might giveyou a perk at one point becomes the dose you need just to get to your base level. Caffeine increases dopaminelevels in the same way that amphetamines do. Dopamine is a neurotransmitter that activates the pleasure centerof the brain. In this way, caffeine works in the same way as heroin and cocaine, albeit at much lower level. Themanipulation of dopamine levels in the brain is what likely powers caffeine addiction.
This relationship with caffeine can have longer-term effects that build on themselves. Once the adrenaline wearsoff you have to pay that stimulant debt back. In exchange for feeling extra peppy and happy, you feel tired andgrouchy for a while. Because caffeine can stay in your body well over half a day, an afternoon cup will stillleave you with some caffeine in your blood stream at bed time, disrupting adenosine activity and depriving youof quality sleep. You drink a morning coffee to get the adrenaline going again, and the cycle begins.
Most people don't realize how much caffeine they ingest. A 6oz cup of coffee has about 100mg of caffeine.
When you see people walking out of Starbucks with "venti" size drinks, it's absolute insanity. A shot of espressoonly has 50mg of caffeine, but in that case you're only talking about 1oz of actual liquid. This is why espresso issuch a popular way to ingest caffeine as an ergogenic aid. A double shot of 2oz has as much caffeine as a full12oz cup, (or a 200mg Vivarin tablet), but in a more concentrated form.
The main intent of this article was to show the additional stress daily caffeine has on your body, and thenegative aspects of "running hot" all the time. But what about caffeine as an ergogenic, or performanceenhancing substance? You can pull lots of articles up on PubMed <http://www.ncbi.nlm.nih.gov> to prove ordisprove pretty much anything you like, but it's good to do some research there. Studies have shown caffeine, when consumed at about 3-10mg per kg of body weight, can increase endurance by prolonging time toexhaustion, burn fat at a higher rate, lower perceived exertion, and increase heart rate and alertness bystimulation the central nervous system. At the same time, it may lower performance by working as a diureticand increasing dehydration. Caffeine is also banned in USOC regulated sports like cycling at a level over 12micrograms/milliliter of urine, which translates to an average of about 4 cups of coffee or 2 Vivarin. Naturally itvaries on body size and hydration levels, so don't use me as your guide for what constitutes cheating or not.
Clearly, if you're using caffeine on a daily basis just to make it through, its ability to serve as an ergogenic isreduced. Additionally, if you're impairing your ability to recover from training on a daily basis by puttingyourself through the ringer of caffeine addition, your performance and fitness level will be impaired as well.
And clearly, overuse of caffeine on a hot day is not a risk work taking.
Coffee or caffeine in moderation each day might not be detrimental to overall health, but it's still important foran athlete to understand the effects of everything they put in their bodies in order to be able to make informedchoices. If you don't like the way you feel when you take a day off from coffee or cola, perhaps that's your signto consider the hold it has on your body and mind.

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