Working as a paramedic I often attend people who have fallen and, though they are uninjured, are unable to get themselves up. If they have been lying on the floor for an hour or longer they almost all exhibit the same strange symptom. When helped to stand, they lean backwards and if not supported would fall over. Sitting these people upright for a few minutes before standing removes the problem. What causes this and why do they always lean backwards?

Nich Woolf