The Effects of Caffeine Consumption on Exercise
Coffee. It’s America’s favorite drug, whether we want to admit it or not. Most adults wake up and have a cup before they start their day, myself included. On the Facebook fan page, Maribel posed the following question “Is caffeine actually beneficial for workouts?” I think many people are as confused as Maribel since there seems to be a lot of conflicting information out there regarding caffeine and the athlete. I decided to get down to brass tacks and research some medical journals to get the final verdict on caffeine and its effects on exercise.
The only case studies available that relate to athletes and caffeine involve sprinters and long distance runners. Since there were no studies that research the effects of caffeine on weightlifters, I am going to use the information regarding the sprinters, since that would correlate more closely to short length, high energy outputs like weightlifting.
When people hear caffeine, chances are that coffee is the first thing that comes to mind. Coffee was discovered over 1000 years ago, and approximately 70% of Americans drink coffee on a regular basis. Although a thousand years have passed, there is still mystery and controversy that surrounds caffeine. Caffeine is easily absorbed by the stomach and intestine and its blood levels peak about 45-60 minutes after ingestion. First and foremost, caffeine is known for its stimulating effects on the brain, but there are numerous other physiological responses that occur as well. Fat stores are broken down and fatty acids are released into the blood stream, blood pressure, pulse rate, and stomach acid production are increased. For most people, these effects last a few hours, although some users report the effects lasting up to 12 hours. Within 4 days of regular use, the human body develops a tolerance to many of the effects of caffeine. This tolerance response to caffeine is one of the quickest built drug tolerances currently known. While caffeine can increase blood pressure and pulse in a first time user, one who regularly uses caffeine will not experience any significant change.
Like with any drug, There is a benefit-to-risk ratio. So, before using any drugs, it is important to see if the potential benefits outweigh the risks.
As a stimulant, caffeine offers temporary benefits of improved concentration, enhanced memory, and extra energy.
Coffee offers antioxidants, like flavanoids.
Coffee contains minerals such as magnesium and chromium (probably not due to the caffeine, since the study was conducted using decaffeinated coffee).
Coffee becomes part of a ritual for many users, with a following that resembles a cult.
Like any drug, high rates of dependency occur, faster with caffeine than other drugs, possibly due to its social acceptance.
Caffeine has been shown to raise blood sugar levels in those with type 2 diabetes.
Withdrawal symptoms such as headaches can occur as soon as 18 hours following the last dose of caffeine and may worsen with exercise.
Despite a vast amount of research in this area, the role of caffeine as a performance enhancing drug is still controversial. Due to ways that studies are designed and what methods are used, the data is somewhat conflicting. However, the general consensus is that:
1. Caffeine can enhance performance in endurance sports
2. Caffeine does not appear to benefit short term, high intensity exercise.
Glycogen is the principal muscle fuel and when it is depleted, exhaustion occurs. Fat is a secondary tool and is much more abundant. Caffeine mobilizes the stores of fat and encourages working muscles to use fat as a fuel. This allows for a prolongation of exercise by delaying the depletion of muscle glycogen which is why caffeine is more beneficial to longer duration exercises versus short, intense workouts. Glycogen saved at the beginning of exercise is thus available during the later stages of exercises. Although the exact method by which caffeine does this is unclear, caffeine caused sparing in all of the human studies where muscle glycogen was measured. The study results were that subjects were able to exercise longer until exhaustion occurred.
Although there have been many studies that suggest a relationship between chronic diseases and chronic caffeine use, it has been difficult to prove a cause-and-effect relationship. This is due to many lifestyle variables that occur in test patients (smoking, exercise, alcohol dependence, genetic inheritance and forms of caffeine intake, such as coffee, soda, and tea). There is currently no evidence that caffeine causes cancer, stomach ulcers, or high blood pressure.
So before you decide to start drinking coffee, do your homework first. It has benefits and risks, just like any other drug. I will continue to drink my cup of coffee every morning, but I never have more than 1 cup a day. Coffee can obviously keep you awake at night if you drink it too late in the day. And if you are having 4-5 cups a day, don’t kid yourself–you have a drug addiction, a socially acceptable one.