Drink for the reason that around 70% of your body is made up of water; used to regulate temperature, lubricate joints and transport nutrients and energy around the body. Dehydration diminishes performance, so when you are training, you will sweat more, add an electrolyte tablet to your drink.
Avoid spikes in blood sugar from high G.I. sugary processed food and snacks eat low G.I carbohydrates which stabilise blood sugar and last for longer in the body.
Avoid overuse of caffeine which interferes with performance
Foods high in saturated fats should be avoided, but your body needs essential fats to process protein, and in endurance events, the body uses fat as fuel. Fish, nuts and avocado are sources of good fats. Supplement your diet with fish oil supplements which contain Omega 3 and Omega 6 will provide added benefits to joints, reducing inflammation, and boosting energy!
To quickly replenish glycogen stores and muscle repair, which continues after exercise for a few hours, eat something small every hour since small meals are easier for the body to process than one large meal.
Training and good nutrition work best together!