The convenience and flexibility of a retractable leash can actually work against you in some situations. It takes practice to be able to use a flexi-leash well, and let's face it, learning how and when to apply the brake, or how much freedom to give your dog, doesn't come easy to everyone.
Many a dog owner has been seen struggling to get control of their dogs on an extendable leash. Obviously, it's harder to control a dog who is 20 feet away from you then it would be if they're on a standard 4 to 6 foot leash. Dogs can easily run out into traffic, have unintentional or invited contact with people or dogs, or get tangled up with another person or dog (which can be dangerous all on its own!).
Another problem is that people might consider using a flexi-leash as a way to give their dog more freedom without actually teaching them a recall. This is not a good idea at all, as is explained below. Retractable leashes are not a substitute for teaching your dog to come back to you.
The handle of most flexi-leashes can easily be jerked out your hand by a strong or enthusiastic dog. The handles are usually some sort of hard plastic and can be both bulky and slippery to hold onto. Once dropped, the leash will retract back into the handle (unless the brake is locked). The dog will end up dragging this noisy, clattering leash - and for dogs that are timid or sound-sensitive, this can be a very scary experience! Some dogs may continue to run away in an effort to escape the scary thing following them.
The retracting mechanism could fail; the leash could stop extending; the button brake might fail; or the leash cord or tape could wear thin and be prone to breakage. Any or all of these can result again in issues controlling the dog or in a runaway dog.
Dogs communicate with one another primarily through body language. The nature of a retractable leash means that the dog is always "pulling", which can look like aggression to another dog. The other dog might decide he needs to defend himself.
Many flexi-leashes are essentially just a thin cord. Like any leash, they eventually wear out (or can be chewed through or weakened by chewing). Should the line or clip break, the tension on the leash can cause them to come whipping back towards you, potentially hitting and injuring you.
Retractable leashes are also notorious for causing cuts or lacerations. Because it's more difficult to control dogs when the leash is extended, it's only natural that people sometimes try to grab the line itself in an effort to regain control. The line cord can easily cut hands, fingers, and wrists, or cause "rope burns". Some of these injuries can be very serious - not just a mere cut that will heal quickly. Likewise, if a dog ends up getting tangled around other people or dogs, the cord can again cut the skin on legs or any other part that comes into contact with it. Plus getting tangled up is a tripping hazard.
Flexi-leashes are equipped with a button that acts as a brake, preventing the leash from extending any further. If the button is pressed while the dog is running, or the dog simply reaches the end of the line, he'll come to an abrupt stop. This can result in neck and spinal injuries especially if the flexi-leash is used with a collar.
Many dogs will enthusiastically greet other dogs; getting tangled up with another dog isn't uncommon. The cord might wrap around their legs, or even around heads and necks, depending on the difference in sizes of the dogs. Dogs can get cut by the leash or they may panic if they feel they're wrapped too tightly and unable to move.
There are circumstances when a retractable leash may be safe to use. When used correctly, in appropriate situations and with the right dog, they are convenient and can make walking the dog a more pleasant experience.
Tip: wrap the handle of the retractable leash with tennis grip to make it less slippery.
Some people may be wondering what they can use to give their dog more freedom and more exercise if they can't use a flexi-leash. First, remember that many parks and municipalities have limits on how long a dog's leash can be, so you may be restricted to a standard leash anyways. But if you aren't, then there are a few options:
Use a bungee leash. A bungee leash is a stretchable leash that allows dogs more room to roam without any extra lengths of leash getting in the way. Typically bungee leashes range from 4 feet to 12 feet, with the shorter lengths much more common. They're mostly marketed as a way to prevent dogs from jerking or pulling hard on the leash.
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