Our inconsistency perpetuates the problem. Some of the time we tolerate the jumping and ignore it. Other times we reward the behavior by exchanging enthusiastic greetings. But when we're dressed up and the puppy's paws are muddy, it's a different story. Reprimanding the puppy for jumping up usually does not work. Either the puppy misunderstands the reprimand as praise or he gets even more excited and the jumping gets worse. If the reprimand is severe enough, the puppy may stop jumping at that moment but it doesn't solve the problem altogether; and it certainly is not a very nice thing to do. It's very similar to a person approaching you with a big smile, arm extended to exchange a hand-shake and you bopping the person in the nose. Even if your puppy learns that jumping up on you is not a good idea, he will usually get away with jumping up on everyone else.
To a dog, space and balance are very important. If you take a step backwards or lean out of a jumping dog’s way, it will continue to jump. To a dog, it is overtaking your space, which only pack leaders are allowed to do. When a dog jumps, step into the dog. Picture a sphere around you and are not going to allow anyone or anything to come into your space. When the dog jumps, step into it sideways with your body, shoulder towards the dog. Don't face the dog head-on (you may not have time to turn so don’t worry about it if this is the case). You are not trying to knock the dog down, although this may happen. Don’t be alarmed if you do knock the dog over. Although you don’t want to abuse the dog by knocking it around, this may actually go a long way toward breaking it of the jumping habit as it will create a negative experience. Dogs are incredibly physical creatures and can withstand a lot of physicality without any harm. The odds of inflicting any serious injury are miniscule. You are simply calmly filling up your space with your body, and in return, setting the dog off-balance, which is an uncomfortable feeling for a dog. Lean slightly forward, not backward. Never lean backward, as you will be giving the dog that space. Casually and calmly, keep filling your space, not allowing room for the dog to come in. Remember, your goal is not to knock the dog down, it's just to retain your space.
An anxious or playful pup may leap high quickly and suddenly “poke” at your face with their nose. That can be triggered by leaning over the top of them especially when they’re in a high-arousal situation like a homecoming or around other dogs. It may be a way for stressed pups to relieve their anxiety, so be aware of situations that cause these behaviors. Dogs control each others' movement with their body language. Think how a Border Collie makes sheep move just by getting close. You can stop your pup’s jumps by stepping close to him just before he leaps. Cross your arms and step into the pup’s personal space before he crouches to leap.
Unless given a command to jump, a dog should never be allowed to jump on humans. A dog that jumps on humans of its own free will is a dog that does not respect the person it is jumping on. Even those cute little toy dogs should not be allowed to jump on people. While you may think it is cute, it is not cute to everyone else. Not only is it annoying to most people to have someone else's dog jump on them, it can also be dangerous. A jumping dog can knock people over, muddy their clothes, put runners in nylons and scratch the skin.