Yes. In one study, 14% of whiplash victims reported the onset of symptoms as having begun 24 hours to one week after the accident. Rear-end collisions unfortunately often result in the types of injury to connective tissue, muscle, nerves, discs, and tendons that may not be immediately evident and may grow more severe with time. What’s more, these injuries can in fact grow worse through neglect. Even non-strenuous daily motion can wear at them until one’s condition becomes serious. Once noticed, they should be promptly and effectively addressed by a medical professional.