'Heavily' in the Bible

And he took off their chariot wheels, and they drove them heavily; so that the Egyptians said, Let us flee from the face of Israel; for Jehovah fighteth for them against the Egyptians.

I was wroth with my people, I profaned mine inheritance, and gave them into thy hand: thou didst show them no mercy; upon the aged hast thou very heavily laid thy yoke.