It is said that Caffeine is the primary ingredient in all the pre-workout supplements available on the market. Caffeine does improve performance during endurance contests when consumed in doses of 3 to 6 mg per kg (but it varies according to the size and weight of the body). Taking one or two cups of coffee 45 to 60 minutes before a training session can easily provide enough caffeine to support one's performance.
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It has a lot of facts and saying by Arnold Schwarzenegger. He supports the theory and provided details on how caffeine can contribute to several factors.
I have also attached the picture below that tells the quantity taken according to the quality of workout:
YES, Because caffeine can enhance physical performance and cognitive function, it is a popular pre-workout beverage. Although research has shown it can improve athletic performance, especially in endurance athletes, be aware of the risks of caffeine. For example, it can cause insomnia, jitters, and stomachache.