In the past couple days, anti-doping Norway is up in arms over the caffeine-cola mix that was given to Norway skiers prior to the climb up Alpe Cermis…. In my eyes, this is a case where an important organization in sports is blowing hot air for no good reason. Lars Engebretsen (Norwegian Olympic Sports Federation Chief of Sports Medicine and Chief Physician for the Norwegian Olympic Team in Athens and Torino) thinks that anti-doping Norway are over complicating things, saying that they should be investigating more important anti-doping areas such as EPO and anabolic steroid use. I must say I have to agree with him.
There has been an ethical debate around caffeine for the past couple decades. When caffeine was on WADA’s banned list, the legal limit was anything under 1200 mg/L. The main reason caffeine was taken off the banned list was because the effect it has on individuals varies greatly due to body size and caffeine tolerance in individuals.
To better understand, we can look at caffeine tolerance at the molecular level. Tolerance to the drug is much higher in those that already ingest caffeine because the body had adapted to the presence of the drug by increasing adenosine receptors in the body, specifically in the central nervous system. Adenosine is very important in the body as it is the backbone of adenosine triphosphate or ATP, the body’ energy currency. Therefore, adenosine is everywhere in the body. Without ATP our body’s would become catatonic due to rigor mortis, but that explanation is for another post.
Caffeine is structurally similar to adenosine, so when it enters the body, the drug can bind to adensoine receptors without activating them. Thus, caffeine acts as a competitive inhibitor. This is very apparent for those that have coffee to wake themselves up. Adenosine acts as a neuromodulator which inhibits the arousal center of the brain. If caffeine blocks the adenosine receptors without activating them, then the arousal level of the body increases. Those who rarely ingest caffeine will have a greater change in metabolic rate when the drug is ingested because they will not have as many adenosine receptors; therefore, when caffeine enters the system, a larger percentage of the adenosine receptors will be blocked and won’t be able to be activated by natural adenosine. Hence, caffeine causes arousal->increase in metabolic rate->increased heart rate. If our heart is pumping faster than we have the ability to from point A to point B in a shorter period of time.
When applied to endurance sports, caffeine binds to receptors on the surface of heart muscle cells which leads to an increase in the level of cAMP (cyclic adenosine monophosphate), which mimics the effect of epinephrine. cAMP then activates protein kinase which increases the rate of glycolysis. This in turn, increases ATP production and availability. If their is more ATP, then muscle contraction can occur more frequently and at more powerful contraction speeds due to limited muscle fatigue.
Another way that caffeine increases endurance is by “increasing fat utilization and decreasing carbohydrate utilization. Caffeine mobilizes free fatty acids from adipose or intramuscular triglyceride by increasing circulating epinephrine levels. The increased availability of free fatty acids increases fat metabolism and decreases carbohydrate utilization. This delays glycogen depletion and so enhances endurance performance.”
Turning the corner, we now look at the ethical dilemma. This debate (for me at least) arises from WADA’s code when deciding if a drug should be banned. There code is as follows:
1) It “endangers the athlete’s health”;
2) It “enhances sport performance”; or
3) It “violates the spirit of sport.”
The wording of their second rule is what bothers me most, especially with the second code. “Enhances sport performance”. This could mean that Gatorade or eLoad could be banned as they aid endurance by replenishing the body with readily available glucose. Carbo-loading could be banned due to the ability to maximize glycogen levels in muscles and the liver. Whey protein could be included due to its ergonomic aid in the bodies ability for muscle recovery. Caffeine certainly enhances performance by the ways listed above, but to have it on the banned list is absolutely ludicrous. I personally believe that caffeine should have never been put on the WADA banned list. Another training module that falls into this “ethical dilemma” is training at altitude and hypoxic chambers. If you are more interested in this subject I wrote a paper on it at school last year and I’ll have it as a post in a couple days.
Til Next Time.