I'm 5'9" and weigh about 150, and can run track. One of the other articles referrs to her as a "tall girl." I've been this tall since middle school....it's possible!
I just can't imagine a 13 year old weighing 150 pounds and running track. When I was 13, I probably weighed about 100 pounds. 150 would have been fat. I guess if she's 5'10" or above she could carry it. I just can't imagine a 13 year old being that big.