Your main source of fuel during exercise is carbohydrate. You therefore need to ensure sufficient supplies to maintain performance. The carbohydrate you eat prior to exercise is more effective at enhancing performance than the carbohydrate you consume during exercise. Take your carbohydrates around three hours before exercise if possible so that they are properly digested before you begin training. You can consume up to 100g of carbohydrates before training either through foods or a carbohydrate replacement drink.
Ensure you have plenty to drink before exercise as well. Around two hours before exercise have about 500-600mls of water. Then about 15 minutes before exercise drink another 500mls.
During Exercise: Ensure you keep yourself hydrated by drinking about 150-350mls at regular intervals (every 15-20 minutes if you can). You can drink water, or if you are exercising for a long period of time have an isotonic drink. Sachets with electrolytes in are great at keeping your mineral levels balanced. Whilst you are sweating, you are losing vital minerals and can get headaches later in the day.
You have a two hour window after training when you need to replenish your body. The optimum recovery time is 30 minutes.
After training, your first step should be to re-hydrate with sips of cold water. Ensure you drink at least four glasses of water before any food. You can then eat or drink some carbohydrates. The body makes glycogen (the name given to glucose stored in your muscles and liver) very quickly in the first two hours after exercise, so this is a maximum time to replenish your muscle glycogen stores. At this stage, if you have been training very hard or just done an event it is OK for you to eat refined carbohydrates or have a recovery drink as you need to get glucose to your muscles fast.
Once you have re-hydrated and taken in some glucose, you can then have a meal which includes complex carbohydrates and protein. Complex carbohydrates are much more effective at replenishing glycogen levels than refined carbohydrates, and help maintain energy levels after exercising. If you have been training in the morning, ensure that you eat regular snacks which include complex carbohydrates throughout the day to maintain glycogen synthesis (e.g. oatcakes and hummus, fruit and nuts, rye bread and nut butter). You also need protein in the recovery period since if you don’t eat enough protein you will break down muscle as fuel. Therefore include protein in your meal or have a protein shake.