Budhia Singh, as shown in this months runners world, ran 40 miles as a 4 year old, and had a coach. I think this is ridiculous. Passed out on the run and couldn't complete the other 3 miles. Now is considered a "wonder boy" in India. His controversial coach was even shot dead.
Second grader, 8 year old Zhang Huimin, who weighs 41 pounds gets up and runs 41 kilometers before school has high hopes for the 2016 olympics. Experts say her tiny body is likely to give out if she keeps running like this. Well of course it would she weights 41 pounds my cousin is 8 and she weights 60. At 7 she completed a marathon in 3:28.45, about 8 minute pace.
I really do not think it is even right for parents to allow their children to run miles like that at such a young age. Parents should wait until their childrens bodies have grown and let them develop before they run like that.