However, it's not the training that makes you fitter - it's your body's response to that training - so the body actually gets fitter between training sessions.  Many athletes make a great mistake by believing that all they have to do is train until it hurts, in order to get fitter and faster, BUT that's not the whole story:-

Training too hard, too often can result in injury, illness and chronic fatigue

SO: -

	Have a balance of sessions in your programme
	Do not schedule hard sessions on consecutive days
	Get enough recovery between sessions (this may be active recovery such as easy running or an alternative activity, perhaps swimming)
	Your body will respond best to a consistent lifestyle with a good sleep pattern
	Make sure that you eat well (include plenty of fresh fruit and vegetables in your diet) and try to avoid junk food
	Drugs and excess alcohol will only inhibit your ability to get fitter
	If you are ill do not train - wait until you feel fine before you start to build up your training once more (start with easy running)

Now for The Second Golden Rule of Training