If the slaves had more time on the ship's deck during the crossing, gaining exercise and fresh air, they arrived in better condition.
This was measured against the greater risk of revolt when slaves were unshackled, and the cost of employing sufficient crew to control unshackled slaves.
- Few enslaved Africans recorded their experiences on the middle passage so it is difficult to say exactly how often they rebelled
- Most resistance appears to have taken place whilst the ships lay off the African coast. It is estimated that rebellion occurred no more than once every 10 voyages
- Most rebellions were quickly and severely put down