I have two boys one 11 and the other 7. The are not phenomens but good athletes. When my 11 year old was 9 he ran 70 for 400m and 30 for 200m and 12 ft- LJ. My 7 year old ran in competition for the first time last summer at 6 he ran 16.5-100, 35-200, 83-400 and 10ft-LJ. They only worked out three days a week in which they would jump into workouts I gave older summer track kids. Example Workout: 6×200-Mon, 4×30, 4×40, 4×50-Tue, and Broken 2×300/150 run 3 walk back 50 run 150. No times were given or pressure just told them to have fun and put forth their best effort. And some days they would not do the works just run around on the Football field until I finished practice then we would go do LJ work.
So how much is to much? And how soon is to soon? I have my own opinion but I would like some feed back and other thoughs on this topic.