When used sparingly as part of a well-designed training and nutrition plan, pre-workouts are generally not bad for you. It's when pre-workouts are abused that they may have harmful effects. Always use the pre-workout as instructed on the label. In addition, it greatly depends on the specific pre-workout you choose, as some have been found to have potentially harmful ingredients. We recommend choosing a pre-workout that is third-party certified to ensure it is free of contaminants and banned substances. Or alternatively consider using energy drinks.