In women 's 100m final , 17 - year - old Kayla Richardson won the gold medal .
In women 's 100m final , 17 - year - old Kayla Richardson crowned the queen of sprint but it was only after decided by the photofinish camera .
In women 's 100m final , 17 - year - old Kayla Richardson won the gold medal and crowned the queen of sprint but it was only after decided by the photofinish camera .