Hi everyone, please give me your advice about my dog health. I am bad at explaining so bear with me. My dog is 4 years and a few months old. He is a local breed, which is hard to describe. Basically, people in the mountain area doesnt really care how their dogs breeding so there is official record about this breed. This dog breed live very well on rat, small animals they hunt, human food, and known for living more than 10 years. My dog is a left over in his litter, very small when I got him, but already changed his baby teeth. I have him fixed about half a year later. He grow up well, at 19kg when he is about 1 year old and now, only put on 0.5 kg more, so I think he is not overweight. He look very fine, well defined muscle, perfect hair. The problem is since the last year, I notice he become less and less active. He dont play with balls anymore. He used to be the fastest dog at the dog park, other dogs whine and cry when they can catch him. Since the last year, he run less. Now, he only run a tiny bit, not even fast, then walk and lie down. I took him to the vet, but they said he is in very good health, it is normal, my dog is fixed so he will be lazy and get old quicker than the male dog. I dont know if I should worry or not, but honestly I am freaking out. Should I tried to exercise him more? I never put him on collar before, only use harness. It is impossible to drag him to run when he dont feel like running, but I afraid using collar will hurt him.