How did the atlantic slave trade lead to the stagnation of africa's culture and economy?

The Atlantic Slave Trade meant that huge numbers of men and women (and children) from Africa were kidnapped and sold by slaves - de-populating the country. Also, it made it profitable to kidnap fellow Africans to sell them rather than focus on development - and this is what many African rulers did. 

You can drink laxative, or  do this exercise when you are sitting in the bathroom on the toilet. to relieve  constipation  fast or in about 1 minute, pinch your nose after your usual exhalation. start holding your breath. but do not mouth breath during this just hold your breath.