Pre-workout is a supplement usually taken by strength and endurance athletes to boost energy, improve workout performance and promote muscle growth. Common ingredients include caffeine, carbohydrates, creatine monohydrate, and it can be taken as pills, powders to mix with a drink, or even be combined with protein supplements.
Article source: https://www.huffingtonpost.co.uk/entry/want-a-better-workout-heres-what-experts-say-you-should-eat-before-and-after_uk_64008338e4b0bdb99f4a4b9a