How Do I Make My Puppy Muscular?

You should always be very careful in the amount of exercise that you place on your puppy. It takes time for the growth plates to close. You don't want to pile too much exercise onto a young pup and stress their tender young joints too quickly.

Walking them daily is a good start and will help build their tolerance levels up slowly and not stress or overtax their joints. Once they reach about a year old, you could begin to slowly build their stamina further by biking them along side you. There are a couple bike adapters that attach to your bike frame to keep them at your side while you ride. Do NOT make them run! Keep it at first to a brisk walking pace for them - and slowly over time increase your speed to where they trot/job along side of you.

Best of luck!