How do I eat during the day for maximum performance?
Before we dive into this, let me first emphasize that meeting your overall calorie needs for the day is more important than macronutrient timing. Assuming you are eating the appropriate amount of energy for your goals, we can look at macronutrient timing.
Carbohydrates fuel performance and protein helps you recover.
Therefore, you should eat more carbohydrates and and protein around your workouts.
Before training, emphasize carbohydrates with a moderate amount of protein and small amount of fat. I usually recommend between 40-100 grams of carbohydrates depending on your size and the intensity and length of session. If you are a smaller athlete and your session is lighter/less intense, air on the lower end. If you are a larger athlete going into a heavier/longer/more intense session, you should eat more. Depending on your body weight, aim for about 15-30 grams of protein prior to a training session. By eating protein before, you can help reduce the amount of muscle damage and kick-start the recovery process proactively as protein takes longer to digest . After eating a protein source, amino acids circulate in our blood stream for a few hours. So eating a consistant sources of protein throughout the day can ensure constant availability. Before training, keep your fat lower as fat slows digestion and usually causes more GI distress. That being said, some people can tolerate fat prior to training better than others. A lot of pre-workout nutrition comes down to personal preference.
Post training is similar to pre-training except I usually recommend eating a little more food than pre-training simply because you won't be exercising right after your meal. If you have readily availible nutrients after training, it will help restore glycogen and help repair the muscles that have been stressed. Usually this ranges from 50-125 grams of carbohydrates and 20-30 grams of protein. Similar to pre-training, keeping your fat low is best as fat slows digestion.
What about the rest of the day?
This is where you are going to add in the fat you did not consume surrounding your training sessions. Aim for healthy fats such as nuts, seeds, avocadoes, olive oil and fatty fish. Low to moderate levels of fat from animal sources such as eggs and meat are also good.
This is also a good time to include lots of fiber and micronutrient rich vegetables. Eating two cups of broccoli before training is likely not a good plan, but if you train in the morning, broccoli paired with a healthy fat, starchy complex carbohydrate and protein source is a great afternoon meal option.
What if you have multiple sessions a day? This is where it gets tricky. Ideally, your sessions are split at least 4-6 hours apart so you have enough time to eat and recover between. If you have 4-6 hours, have a regular meal airing on the side of more carbs and protein. Here is an example:
2 sessions: 1 session from 9-10:30am and the 2nd session from 4-6pm;
A post-workout carb and protein meal at 11am, and then a 'regular meal' with lots of carbs, protein, and moderate fat levels somewhere between noon and 2pm.
If your sessions are close together (under 3 hours) or it's a multiday event, it can be harder to navigate as it may be difficult to eat a regular meal without GI distress. Keep your meals high in carbs with some protein. It may be easier to do liquid forms of food such as gatorade, dextrose, protein power or baby food.
At some point you will want to eat some solid, 'real' food, but you may have to load up during periods of the day when you aren't training or competing. This may be in the morning if your sessions are in the afternoon, or in the evening if your sessions are during the day. This might mean a lot of vegetabels and healthy fats cramped into a meal.
A lot of nutrition and macronutrient timing comes down to personal preference and trial and error. Some people can toleate eating a lot right before training while others are good with a banana. Again, it's more important to ensure that your total energy needs are met before getting concerned about meal timing. A good general rule of thumb is carbs and protein around training times. Fat and fiber during rest periods.