During training
Do you think the training will be more effective? Are you afraid of consuming too many calories? I really don't know. But you're doing yourself a disservice.
During almost any workout, you need to replenish your carbohydrate intake. But how much should you consume?
The content can vary widely. And you need to know what to look for so you consume enough during your exercise.
Mixing your own sports drink is easy and doesn't take a lot of time. It's also cheap and you get optimal concentration.
Too little fluid leads to poorer physical performance but also leads to poorer decision-making skills, longer reaction times and reduced concentration.