ABSTRACT
The function of sleep is one of the enduring puzzles of Biology. One idea is that it serves some recuperative function, and therefore we sleep longer after a day of physical exercise. Another view is that it is to do with processing information acquired the previous day, so we might expect to sleep longer after a day of mental activity. In an experiment to test these ideas against one another, 36 students were asked to time their continuous sleep after a day of strenuous physical activity, and again after a day spent attending classes. Exactly how a study like this should be designed is discussed further in Chapter 4, but we would obviously pick the students at random, possibly have only one sex, or else equal numbers of males and females. It would also be a good idea to do the exercise day first for half the subjects and second for the others. The data collected are shown in Table 3.1. How do we test the hypothesis that sleep is affected by exercise?
