You can take your dog cycling with you at any age, except when he is a small puppy.

With a few precautions and a bit of conditioning, dogs are natural biking partners. Most dogs love to get out and run, but size and endurance are important considerations. Among the best biking partners: Akitas, Labradors, huskies and collies.

You can take your dog cycling with you at any age, except when he's a small puppy. Most well-conditioned 2- to 5-year-old dogs can maintain a speed of about 10 mph for about an hour or more – just right for trail riding. There are some dogs, however, that aren't designed to be out in the heat as much as other dogs, namely snub-nosed dogs such as the bulldog and the Pekingese.

Start your dog's conditioning program slowly, going just a few miles each day, building up distances gradually. If your dog is over 5 years old, he will have gained some weight and will begin to slow down, so ease up. Your dog can run with you for many more years, as long as you don't overdo it. If your dog lies down during training or lags behind at a speed under 5 mph, end the session immediately. Keep in mind, too, that we're talking trail riding here. If you're going to be riding on pavement or in traffic, do the dog a favor – and leave her home.

Running is the essence of life to dogs, and often they don't know when to quit. It's up to you to recognize signs of heat exhaustion. Sled-dog runners use the 120 rule: If the combined total of temperature plus humidity equals more than 120, they don't run their dogs. Follow their example.

While out on the trail, "watch for lethargy, disorientation and sloppy foot movements" says Tracy Howard, a veterinary technician. "If you see any of these signs, stop immediately, and get your dog water. A dog's normal temperature runs higher than that of humans – around 100 to 102.5 degrees. They only sweat in their pads and panting helps keep them cool. It would be a good idea to plan your trip near water so if the dog needs to cool off, he can just jump in.

Be on the lookout for hazards: poisonous plants, dangerous wildlife or other aggressive dogs. A major hazard in trail running is the thorn or grass awn, which is a small spear-shaped seed that can lodge in your dog's eyes, ears, nose, paws or puncture the skin, particularly in the soft tissue under the leg. "We see hundreds of dogs with grass or cheat awns in them every year," Howard says. "If it's in the paw or skin, you might be able to remove it with tweezers. If your dog starts limping during a run, stop immediately and inspect his foot, and pull out the offending awn."

If the awn lodges in the nose or eyes, things get more complicated, says Howard. "If your dog starts sneezing uncontrollably or scratching at his ears and continues for several hours, take him to the vet."

Most dogs can run for years without any trouble, but a common injury, known as a torn anterior or cranial cruciate ligament, can occur in active dogs. If your dog shows signs of soreness or has trouble getting to his feet, take him to the vet. The most common running-related injuries are worn down pads. You can avoid this by using Pad Guard®, a spray that is applied directly to your dog's feet. It forms a protective barrier and works better than booties.