Fartlek, which means "speed play" in Swedish, is a form of conditioning which puts stress on the whole aerobic energy system due to the continuous nature of the exercise. The difference between this type of training and continuous training is that the intensity or speed of the exercise varies, meaning that aerobic and anaerobic systems can be put under stress. Most fartlek sessions last a minimum of 45 minutes and can vary from aerobic walking to anaerobic sprinting (source ~ Wikipedia).
Decided to keep my first Fartlek session fairly modest and so this evening in steady rain and after 10 mins warming up jogging had 4 x 1 minute sprint sessions seperated by 4 minutes jogging to recover. Cooled down with a 2 minute walk home. Covered 3 miles in just over 30 minutes. Not as bad as I thought it might be! I'll increase this over the next few weeks...
