A sign on the wall of my local coffee and tea shop said, "Any unaccompanied children will be given a large cup of espresso and a free puppy!" That is the kind of picture that strikes terror in a parents heart. It is even more scary when you add a bunch of sugar to the mix. All you can do is try to remain sane until the effects wear off and they finally crash. There can be no doubt of the effect caffeine and sugar have on the mind and the body. The average American drinks at least three cups of coffee per day. That converts to 300 mg. of caffeine per day. Caffeine is the drug of choice for many people including athletes. According to some scientific studies, caffeine has even been shown to enhance performance. When taken in moderation, the caffeine in coffee has shown the ability to increase athletic performance.[A study conducted in 1979|http://www.ncbi.nlm.nih.gov/pubmed/481158] showed a 7% increase in distance cycled over a period of two hours in subjects who consumed caffeine compared to control tests. Other studies attained much more dramatic results; one particular study of trained runners showed a 44% increase in "race-pace" endurance, as well as a 51% increase in cycling endurance, after a dosage of 9 milligrams of caffeine per kilogram of body weight. The extensive boost shown in the runners is not an isolated case; additional studies have reported similar effects.[Another study found|http://www.ncbi.nlm.nih.gov/pubmed/7749424] 5.5 milligrams of caffeine per kilogram of body mass resulted in subjects cycling 29% longer during high intensity circuits. The Olympic Committee has banned athletes from having more that 12 mg/ml in their urine samples. This equates to approximately 4 - 7 cups of coffee consumed within 30 minutes. What is it about caffeine that improves endurance? Early studies concluded that caffeine spared the glycogen in the muscle from being used as energy and switched over to fat reserves instead. As we all know, running out of glycogen is the point where the body comes to the point of "Hitting The Wall." This is where you run out of gas and feel like you are dragging a 1000 pound weight. Recent research, however, indicates that caffeine plays another, perhaps more important role, in delaying fatigue by increasing the levels of dopamine in the brain. Dopamine is commonly associated with the pleasure system of the brain, providing feelings of enjoyment and reinforcement to motivate a person proactively to perform certain activities. So maybe the positive effects of caffeine have more to do with "mental energy". How does caffeine work? Caffeine is a psychoactive stimulant drug having the effect of temporarily warding off drowsiness and restoring alertness. When found in coffee, it contains another drug called Theophylline which is used for respiratory diseases like COPD or asthma. It relaxes the smooth muscles in the bronchial tubes so you can breathe easier. It can also increase heart muscle contractility and efficiency, blood pressure, renal blood flow and has anti-inflammatory effects on muscles and joints. The role of Adenosine in the brain is to promote sleep, supress arousal and slow metabolic activity. The brain is full of Adenosine receptors that are programmed to receive Adenosine molecules. Caffeine molecules are almost identical in structure to Adenosine molecules. The brain receptors cannot tell the difference and so they receive them instead and thus blocks the Adenosine molecule from doing what it is supposed to do. This is the stimulating effect of caffeine. Too much of a good thing It depends on your personal sensitivity to caffeine, but the average person can take up to 300 mg. per day without many side effects. The benefits of caffeine on athletic performance are more pronounced on someone who has not built up a tolerance for the drug through regular consumption. When they take it right before an athletic event, it affects them more than the person who drinks several cups per day. Too much caffeine can be troublesome. Since it is a diuretic, it can cause dehydration if you are not drinking enough water. Not only that, but it also has a laxative effect. If you are doing a triathlon or a long event, this could cause you to stop more often to urinate or look desperately to find an outhouse or port-a-potty ! Not fun. If you over do the caffeine thing there are other problems you should watch out for. Increased anxiety and panic attacks Increased blood pressure Bowel irritability Insomnia Increased gastric acid Large doses of over 500 mg. per day could lead to caffeine intoxication which could lead to: Vomiting Fatigue Sweating Palpitations Chest pains Neurological symptoms Diarrhea |A Few Common Sources of Caffeine| |_Source_|_Caffeine_| |8 oz Brewed Coffee|135 mg| |1 oz Expresso|30-50 mg| |8 oz Green Tea|25-40 mg| |8 oz Black Tea|40-70 mg| |12 oz Coca-Cola|34.5 mg| |12 oz Diet Coke|46.5 mg| |12 oz Mountain dew|55.5 mg| |SoBe No Fear|158 mg| |1.45 oz Sweet chocolate bar|27 mg| |Exedrin|65 mg| What About the Effects on Creatine? Creatine is known to help with endurance and many people take supplements to enhance their performance. Studies show that caffeine can completely counteract the effect of taking Creatine supplements. Advice to people taking Creatine as a supplement is to avoid caffeine found in food and drinks. Conclusion... Yes, caffeine could enhance your performance and some studies suggest it is up to 60%. This is not a replacement for a healthy diet and good hydration, all of which will definitely help you train better and reach your fitness goals.