I think so, too. My family is also a Teddy, 1.3-year-old boy. I take him out for a run every morning and evening, in fact, for my weight loss. He is a sparring partner. However, after such a period of time, I found that both of us have improved obviously. I think it's a good way, but it's best to tie him up to avoid fighting with other dogs. Your family is a puppy sister, and the probability of conflict is less, but I still suggest tying him up. I wish you the best of health!