Now this one is for those fitness enthusiasts and athletes who actually try their best to eat clean and train, but aren't properly loading their meals during the day, and then suddenly it's time to work out. Hm. What to do, what to do...
Now the closer you get to your workout, the less you should eat. Your body does not want to work that hard on a meal digestion and fuel output and fat metabolism and muscle regeneration and blood detoxification. In fact, it can't. The body only wants to do a very limited number of additional actions on its road to keeping homeostasis. So it makes a decision to digest the food, thereby using all of your available energy for digestion, leaving very little for your workout. To add to this, if it contains high fats, it becomes even more unusable to the body for the workout, leaving you feeling less worked out yet more fatigued than ever.
Ideally, your bigger meal should be about 3 or 4 hours from your workout. This should be your last substantial meal, given this theory. Any food you take in should become easier to digest and assimilate into the body down to that last hour (protein shake or very small easily digested meal). I have been okay with a small portion of nuts or an apple 2 hours prior to my lift session, but I feel best on a protein shake (liquid nutrition) 1 hour before and coconut water during my workout. This seems to be the optimal intake window.
Some dietary theories suggest that you eat very little during the day, have a protein shake before, and then eat a hearty meal after your workout. Others suggest that you load a majority of your proteins and limited healthy carbs (depending on the theory is what type of carb that may be suggested) every 3 or so hours until your workout. What I'm finding is, each person needs to find their groove, and experiment to see how optimal the workout session feels. If you feel heavy, you ate too much. If you feel lightheaded, you didn't consume enough. If you feel pretty energetic and balanced, and can perform your regular program with a bit of energy to spare, you may have found your program. Keep in mind that sleep and type of food plays a factor in your outcomes. Find that sweet spot. Now stick to it.