Depending on your goal, fitness need,  intensity and duration of the workout,  there is no a rule that can be applied to everyone, if you trying to lose weight eating before a workout will be different than if you try to get stronger and gain muscle mass.  How much weight you have to lose?  how hard and how long will you train?  How does your body metabolize insulin levels? those factors must be kept into consideration when choosing the carbohydrates that will fuel your workout during and replenish it after. The answer to these questions will define the choice of foods and the time those foods will be ingested either before your workout begins and when your work out finishes. m.a.