I dont think theres any genetic barrier that prevents people from running fast. Maybe not competitive but everyone can run at about 11-12 sec/100 meter if they work hard enouph (in my opinion). Thats because all sprinting athletes from all countries over the world have been able to run faster than 11, this hints that genetic barrier is propably at a pace faster than 11...
Theres all kinda stuff to get someone to sprint faster...
Try polymetrics, sprinting at the track, BW gymnastics, agility, a bit of long runs, oly lifting and power lifting (even though he may be young to learn those). And the list goes on...
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