6 miles in 38 minutes is slow for a runner of any kind. I could do that in junior high, 7th grade, when I was a midget.
Last time I ran for time, around 1979, for motocross training, 4.7 miles in never more than 33 minutes, age 30.
During a recent bicycle race, the Cinderella Century, I had to walk just about a mile from the car to registration, SIX times. Average 17 minutes to 20, gimping along and resting as often as overhang shielded me from the pouring rain.