You live with him and take care of him every day. Don't shortchange him now by neglecting to take his nature into account when you decide to make him your running partner. Most dogs are great sprinters but aren't superstars when it comes to long distance running. Knowing the specifics of your dog's breed (or your best guess) and recognizing his limitations will help to insure a safer and more productive run for both of you. Very young, overweight or geriatric dogs may just need frequent breaks. Other dogs may lack social skills and need a slow, planned introduction to the rules of the road and a little tutoring in good neighbor practices when dealing with four-footed and two-legged strangers.