At present, the Anti-Doping Center of the International Olympic Committee says: Doping is the general name of all illegal drugs in the global sports world, and there are many kinds. Commonly used stimulants include stimulants, anesthetics, androgens, diuretics, erythropoietin and so on. The use of stimulants will cause great harm to athletes' body and mind, and it is a major public hazard in competitive sports.

Coffee contains caffeine, which has two functions: stimulant and diuretic. Therefore, the drugs used are strictly controlled, because caffeine can improve people's endurance, thus improving sports performance. Caffeine is a stimulant banned by the International Olympic Committee. According to the regulations of the International Olympic Committee, when the caffeine concentration in urine is >: 12 μ g/ml, it is regarded as positive, that is, doping is used illegally.

According to Hong Kong media survey, a cup of freshly ground coffee with an average medium cup of about 260ml contains caffeine 160mg. However, the caffeine content of different kinds of coffee varies greatly. Starbucks coffee has a high caffeine content.

Drinking coffee before exercise can increase endurance. According to the Encyclopedia of Sports Medicine, combined with laboratory research, taking 3~ 13 mg/kg caffeine before exercise can increase the endurance of long-distance running and cycling. Among them, when the dose of caffeine is 5~6 mg/kg body weight, obvious effect can be obtained. However, caffeine less than 9 mg/kg body weight generally does not make the caffeine concentration in urine greater than 12 μ g/ml.

Let's take an athlete weighing 75 kg as an example to calculate that drinking more than 220 mg of caffeine before exercise will increase endurance, which is roughly equivalent to a cup of medium coffee (about 308 ml). For the best effect, you should drink about two cups of coffee. When the coffee consumed before the competition exceeds 640 mg of caffeine, which is equivalent to drinking more than 3-4 cups of coffee (or 1000 ml), the drug test will be positive.

Drinking a medium cup of coffee before the game will not lead to a positive drug test. It should be noted that the above figures are only a rough guess, because people's weight is different, the caffeine content of different coffees is very different, and the ability of individuals to metabolize caffeine is not exactly the same. From these figures, we can find that drinking a cup of medium-sized coffee before the game can not only improve endurance, but also lead to a positive drug test. In fact, only a few athletes were found to have ingested too much caffeine in drug tests, and almost none of them were caused by drinking freshly ground coffee, but athletes deliberately ingested caffeine capsules, tablets or suppositories.