I to believe the 5 minute rule is a get out clause, I have had GSD for over 26yrs never had one with HD, highest score I have had is 2:4. Mine are allowed free running exercise off lead on soft ground such as fields from 8wks. I belong to several GSD forums and those that do have dogs with HD are those that restrict the exercise. I dont believe in long road walks but free running is fine, a sheepdog is not confined to the 5minute rule!
When vets quote enviromental aspects this starts before conception, the health of the bitch, food etc of the exspectant dam.
HD is genetic, you can make the degree of it worse if the dog as it with the wrong type of exercise, such as jumping. But free running and swimming will help to develop the gluteal muscles therefore stabilising the hip joint.
Heres what I have posted elsewhere;
Contributing factors
Exercising and maintaining good muscle mass may actually decrease the incidence of the disease. Moderate exercise that strengthens the gluteal muscles(there are three muscles in this group they support the upper thigh/hip/bottom area, so help in stabilising hip joints, 1 deep, 1 superficial and 1 middle one), such as running and swimming are a good idea, but avoid exercise that puts strain on the joints such as jumping, i.e. agility until the dog is scored.
Obesity is another high risk factor; avoid overfeeding and supplementation of calcium.
Growing pattern - rapid growth rate and excessive weight gain (above the average for the breed) can both increase the likelihood of hip dysplasia occurring.
Breed - genetic inheritance, latest research; The existence of a major gene in addition to polygenic gene effects was detected. Although only small frequencies were found for the unfavourable homozygotic genotype AA, the probability of the AB genotype was high in affected animals. Selection schemes to reduce the frequency of the allele A should therefore efficiently improve existing breeding programmes in German shepherd dogs.
Muscle disorder - a muscle disease (developmental myopathy of the pectineus muscle) has been described in German Shepherd puppies with hip dysplasia, although no direct link yet proved.
Pam

Some of us have said that our vets tell us that we don't need to restrict exercise for small/medium breed dogs as HD isn't an issue. I think it's important to point out that this is strictly in relation to off-lead exercise under the pup's control. On lead walks, running, agility etc still have age limits or restrictions that need to be observed in order to minimise risk of injury.

And that leads to another issue. Most canine sports have a minimum age.

Are those ages based upon pups that have only had very restricted exercise until a year or more old, or are they based upon pups that have run free from a couple of months old, gradually building up strength, stamina, coordination etc?

Of the sports my dog does the ages are as follows:

Hydrotherapy/Swimming - 6 months
Beagle Racing - 6 months
Cani-cross race - 12 months
Agility Competition - 18 months

Any puppy will be accepted for hydrotherapy at 6 months. The reason for the 6 month rule is that most of the growing has occured by that age.

Only a fit puppy that has been allowed to develop naturally will be allowed to beagle race at 6 months. If it's only ever had short walks on lead it won't be fit to run at 6 months.

Although a dog must be 12 months old on the day of a canicross race, it must train for the race for weeks or even months before hand. A dog that's spent it's early life romping about a field covering miles every day will get racing fit very quickly and probably wouldn't need to do any training until about 10 months old. But what age would a pup that's always had exercise restricted need to start training in order to be fit to race?

When my dog started agility at 12 months old she'd spent 7 months running, jumping, play fighting etc Agility was a push over. Would a dog that's always been on lead be fit to start at 12 months?

My point is that if you do choose to keep your dog on lead for it's first year then it's vital that you put it onto a gentle and gradual training program for quite some time before starting any sports. It's a bit like taking a child that's never been allowed to have proper exercise and expecting it to be able to safely do fitness classes as an adult.

The 5 minute rule and restrictions on exercise concern mainly with forced exercise -- lead walking, jogging, etc. I don't believe that anyone was saying that free running was 'bad' for a puppy, in moderation of course.

. Here's what our vet told us...

She said the '5 minute rule' for puppies is a myth perpetuated by breeders looking for a get out if a pup develops genetic problems. Healthy puppies will only benefit from natural exercise (by natural this just means letting them off lead and letting them run and play to their hearts content. She also insisted that a breed like a beagle (bred to run all day) NEEDS to get off lead every day. She said it's impossible to exercise them enough on lead.

A few months later I had a discussion with another vet and she clarified things further. She explained that in normal, healthy puppies it was in their best interests to let them run and play as nature intended. However, if a dog has HD (which isn't detectable until it's older) then it's possible that the wrong kind of exercise will make it worse. No one is really clear about what the 'wrong kind' of exercise is. Some say on-lead is harmful - other say off-lead is harmful..

I have just had to look up your breed of dog (sorry, never met one!) and they are a large breed, not a giant breed right? I can understand the larger the dog the more careful you want to be with exercise during it's development, but I don't see the logic in keeping a dog on a lead for a year. I would have thought that on-lead only exercise would provide the pup with too much of what it doesn't need -- repetitive 'forced' walking.

Of course, that doesn't mean to say that hours of off lead walking is good for them, but I don't see how short off lead runs is detrimental to them at all. If anything they will be extending and using a wider range of muscles while being able to move naturally off lead than they would on lead, walking at a slow, unnatural human pace.

Sorry I was unclear. The guy that said this to me wasn't an Estrela person, he had Groenendaels. Certainly not large dogs by any means.

I have been reading the other threads relating to exercise and HD etc with interest. Of course my pup is only 7 months and a large breed, so although I would like to do sports with her, I am happy ( of course ) to wait until she is about 2. Just wanted to hear people's thoughts on free (off lead) exercise and running.

I am a dog walker and now due to the loss of two clients (Ellie rehomed and another one fighting) I only do one walk per day. We go to the beach or country park etc. in the car and then I let them play for about 1 hour before heading back. We don't walk to our destinations as Rio is too young for much lead walking. I walk around when we get there, but mostly to stop me from freezing! I lift Rio in and out of the car (increasingly difficult!), BUT what I wanted to ask was - do you think that an hour free play with other dogs is too much?