Athletes work hard for months leading up to competition to ensure that when they stand in front of that first barbell, they know there is not a thing they could have done differently to make themselves better prepared. But these months of intensity, of working on weaknesses and fortifying strengths, can all count for nought if your body doesn't have the fuel to allow your physical capacity to manifest itself.
In the scheme of things, correct competition nutrition takes so little effort, though has so great a reward.
The aim of competition nutrition is different to the aim of nutrition on every other day of the year. Every other day is geared towards long term health. Game day is geared towards MAXIMISING SHORT TERM PERFORMANCE. You would happily trade a week of lower energy levels for the maximisation of energy levels under the bright lights.
Much of this comes down to carbohydrates. On every other day of the year, carbs should be minimised. Carbohydrates cause a major hormonal effect that affects insulin levels and energy storage. Energy is stored as fat. Carbohydrates promote fat storage. Excessive carbohydrate in the diet also contribute to inflammatory markers in the body. But on competition day, short term performance is the priority.
Good overriding advice is to not do anything new. If what you've been doing works for you, keep it up. That being said, the following template is the ideal (or close to it).
The first item on our list for a reason. Hydration is arguably the most important point, and should start week out from the event. Drink loads of water all week. I'm talking 3 litres+ per day. Keep doing this right up to and throughout game day.
Keep a one litre water bottle within 5 metres all week. Just keep drinking.
The Day Before:
Normally, a balance of protein, carbohydrates and fat is recommended. For lunch and dinner the day before, slightly increase your carbohydrates (low GI), but otherwise eat as you normally would (assuming you normally eat healthy). This will just ensure your glycogen stores are topped up.
The only real 'meal' (in a traditional sense) is breakfast. Everything else you consume on game day is a slave to the events, not a slave to societal expectations of eating times.
You want a substantial breakfast. A good combination of easily digestible protein, carbohydrates and fat. Don't do anything new. The combination of three macronutrients should give you a profile your body is used to. Stock up on some good low GI carbohydrates. These will ensure the muscles and liver are stocked full of energy for the day, and will aid in maintaining an even and constant blood sugar level during the energy expenditure roller coaster which is to come.
This is the most important element of competition nutrition.
Consume easily digestible protein that wont take a huge amount of blood away from the skeletal muscles to digest. I suggest a whey protein mixed in water. Easily digestible with a high bioavailability.
Carbohydrates should be consumed immediately. For the fastest 'hit', slam down 20g of glucose powder immediately after an event. Following this, fruit is ideal. Fruit contains fructose, a form of sugar. The combination of fructose (primarily replenishes liver glycogen) and the glucose (primarily replenishes muscle glycogen) you just ingested is a good move. Again, normally too much fructose isn't necessarily a good thing due to it's effect on insulin levels. On game day however, the aim is to replenish the stores of glycogen in the muscles and in the liver. Fructose from fruit is one of the best methods of achieving this. Hepatic (in the liver) glycogen is responsible for keeping blood sugar at a constant level. With multiple events in a day, these extra stores of glycogen are invaluable to prevent periodic crashes in blood sugar and energy levels throughout the day. We want to give our body all the tools to manage our energy requirement ultra-precisely. This is the only time where high GI carbohydrates are a good thing.
My recommendation would be to consume approximately 30g of whey protein and 60g of carbohydrates IMMEDIATELY after an event. These can be prepared as shakes, and kept in an esky that you can reach wherever you fall post event.
Chances are, between events, you'll be in that nasty zone where you're both recovering from the previous event, and preparing for the next one. Nutrition is going to be the last thing on your mind. But remember, you can't run a high performance engine without high performance fuel. Between events you're looking for something easily digestible that you eat on a regular basis. Something that you are comfortable eating that doesn't take much effort. Get some protein, some carbs and some fat - remember, you aren't going to feel like eating.
Graze on 'between event' food slowly. A mass ingestion of food will draw blood away from your muscle. And you just might need them later!
After the Competition:
For post competition recovery, go down the same path as post event recovery, but tone down the GI on the carbohydrates a bit.