We all know that for sports people, caffeine can strengthen the sympathetic nervous system and promote muscle contraction. It is a sports nutritional supplement that enhances training intensity. At the same time, caffeine can effectively reduce glycogen decomposition and extend exercise time, so that people will not Feeling "burned out" quickly.
Caffeine is also a "double-edged sword". Excessive caffeine intake is also harmful to the human body. Long-term coffee consumption may lead to mental dependence, insomnia and bone loss. Generally speaking, a normal person's daily intake of 500 to 600 mg of caffeine (about 7 to 9 cups of tea or 4 to 7 cups of coffee) will have an impact on health; continuous drinking of large doses of caffeine can cause poisoning, manifested as uneasiness. , anxiety, irritability, excitement, muscle tremors, sleep disorders, headaches, sensory disorders, heart and gastrointestinal discomfort and other symptoms. Large doses can even cause epileptic convulsions. Therefore, patients with heart disease and pregnant women should try not to consume foods containing caffeine.
How to recognize the value of caffeine for exercise? Recently, the Journal of the International Sports Nutrition Association published an article "Caffeine and Human Function". The article reached the following conclusions:
1. Compared with the traditional ingestion of caffeine in the form of brewed coffee, ingesting caffeine in an anhydrous state (such as taking capsules/tablets, powder) is more effective.
2. Most current studies believe that consuming caffeine 60 minutes in advance can ensure optimal caffeine absorption. However, some studies have shown that consuming caffeine 15 to 30 minutes before exercise can improve human exercise status.
3. Ingesting small to medium amounts of caffeine (about 3 to 6 mg/kg body weight) can improve the body's physical performance in many aspects. However, the amount of caffeine consumed is not directly proportional to the effect. When the amount of caffeine consumed When it exceeds 9 mg/kg body weight, it will not have a better effect on the body.
4. Caffeine intake can increase physical alertness and excitement during forced sleep deprivation or mental fatigue, such as in special forces soldiers performing special missions and athletes who must maintain concentration even when exercising to exhaustion. All had very good results.
5. Caffeine can effectively enhance the human body’s athletic ability during sustained high-intensity endurance exercise, and has been proven to be very effective in improving athletes’ performance in time trial sports.
6. It has recently been confirmed that caffeine can increase the body's glycogen synthesis during exercise recovery. This is a strong counterattack against the previous belief of individual scholars that caffeine inhibits glycogen synthesis.
7. In sustained, high-intensity sports (such as football, hockey, rowing, etc.), caffeine can significantly improve the performance of athletes. However, the functional enhancement brought by caffeine also has individual differences for athletes. .
8. In some literature, there is disagreement as to whether caffeine improves athletes' performance in strength sports. It is unclear whether this difference is due to different individual training principles, training programs, training levels and other conditions.
9. Specific research on women and caffeine is limited, but recent research hasIt has been confirmed that caffeine has a positive impact on some female athletes with good strength and quality conditions, and can appropriately improve women's sports status.
10. Many scientific literature does not believe that caffeine intake will lead to excessive physical exertion during exercise. In fact, there are many studies that have attempted to prove that caffeine can cause excess sweat rates, total water loss, or fluid balance imbalances during exercise, including exercise under heat stress conditions. It seriously affects the human body's movement state, but these experiments have failed.