Too Much Exercise May Harm Your Puppy

Q. I have a 6-month-old female Golden Retriever puppy. My breeder said too much forced exercise, such as running alongside a bicycle, could hurt a puppy's growth plates. What does that mean and when is it safe to run her with a bike?

A. Your breeder is correct; forced exercise is not good. Large-breed puppies less than 1 year old grow rapidly, constantly remodeling bones and joints. To allow for all the changes, the bones and cartilage are soft and contain many blood vessels. This young tissue is resilient but prone to trauma and stress. Cartilage especially has limited regenerative capability and can be damaged by shock associated with excessive exercise. If the damage is not repaired, normal growth is disrupted.

Dogs with inherited conditions such as hip or elbow dysplasia are at higher risk. Their joints are already more unstable than other pups, and damage can accelerate dysplasia and increase its severity. Owners must be vigilant because pups cannot be trusted to limit their own activity and effects may not be seen for some time.

However, don't over-limit your pup's activity. Proper bone and joint development requires a certain amount of activity and stress on connective tissues. Moderation is best. Leash-walking and light jogging are excellent. Avoid heavy or extended activity on inclines and hills. Running with a bike and pulling an owner on in-line skates or a wagon filled with small children are not good ideas.

When your pup is 12 to 14 months old, you may slowlyover two-month periodsincrease activity levels until adult exercise levels are attained. Watch for signs of joint painlimping, abnormal gait or reluctance to exercise.

A word to the wise: It's difficult to judge a dog's level of activity and fatigue while on a bicycle seat. I have seen dogs with torn and bleeding footpads, lactic acidosis or heat stroke after such exercise. I discourage it and recommend constant observation and evaluation of the dog if you must do so.