Your Post Workout Routine Needs This One Supplement Pre Post Workout Eating 101 | Helpful info from Blogilates. It is absolutely critical that you consume your post-workout meal immediately after exercise. Muscles are depleted and require a wealth of protein and carbohydrates. This is called, “the window,” and it’s when muscles are biochemically primed for nutrient uptake. Ideally, you’ll consume your post-workout meal within 20-30 minutes, and definitely within the hour.