What is the time it takes to recover from whiplash?

Whiplash: Healing is directly proportional to the energy absorbed during the injury. So, harder impact=longer healing time. Generally speaking, this is purely a muscular problem and worsens for a day or two, and then improves thereafter over days or weeks. Rarely does whiplash produce lasting symptoms over 2-3 months (unless a lawsuit is involved, then all bets are off).