How to use the Long Lead correctly
The Fundamentals of Long Lead Walking
In an ideal world, when the dog hears the word “come” he or she should stop what they are doing and run back toward you. But that is not always the case, with many dogs thinking the command to come is not for them.
The foundation or starting point of allowing your dog to walk free is the long lead training. Like any other lead we need to get our dogs accustomed to it first, this is the easy bit as we just walk with them as normal. Giving them time to adjust to the length of the lead allows them to walk or run at that given distance.
watch The next stage requires confidence on our part as we will be dropping the lunge rein and allowing it to drag behind. The trick here is to intermittently stand on the lead, always making sure our dogs are focused on us rather than distracted by a bird, squirrel, rabbit or another dog for example.
follow An alternative would be to introduce either a voice command or even a whistle as the sound of the whistle will travel further than your voice. Using the whistle will also help to disguise your emotion or panic if your dog is running.
By having the lunge rein to step on and the whistle to recall, your dog will always get the right message. Clear and consistent communication is essential and is what a lot of training comes down to. Never set your dog up to get it wrong.
source If we practice these simple fundamentals of long lead walking then over time our dog will cease chasing or running off while out free walking.