"The researchers found that sugar consumption actually lowers people's alertness within 60 minutes after consumption, and it increases feelings of fatigue within 30 minutes after eating. That means chugging a Gatorade before a run or snacking on a Twix to combat the afternoon dip is an act of futility."

Scientists argue that there is no such thing as a sugar rush.

https://elemental.medium.com/there-is-no-such-thing-as-a-sugar-rush-d4ec638e1d67