What can I give my puppy to make it gain weight?

Before anyone says to take my puppy to the vet, I did a few days ago and she has a perfect bill of health. Blood and fecal tests were done; she doesn’t have worms or any other condition that is harmful.

My puppy is growing a lot. She’s getting tall, she can climb up to anywhere she wants, and she gets tons of exercise. I run a lot and she can actually keep up with me.

However, she is getting very thin. She is very energetic and plays outside all of the time with me. I feed her 4 times a day and she still doesn’t gain one ounce of fat. I can see her ribs and her hip bones, and that kind of scares me. I know that being fat would hurt her joints, but I would at least like her to not look like an abused dog on animal rescue show.