Believe it or not, it is not possible to make up for lost hours of sleep. The adverse affects of sleep loss cannot be undone by putting in extra hours over the weekend. Alexandros N. Vgontzas ([insert phonetic spelling here]) discovered this during a 13-day study at the Penn State University College of Medicine.

The study involved a group of 30 individuals. The volunteers slept for 8 hours for the first 4 nights. During the next 6 nights, the volunteerss would be woken up 2 hours earlier. The volunteers were then allowed to sleep for 10 hours in the final 3 nights.

At 3 points during the study, the researchers tested the subjects on the physiological (FIZZ-eeh-oh-LODGE-ick-al) and psychological (SY-co-LODGE-ick-al) effects the study had. The results showed that even though certain hormone levels had re-balanced, their attention span did not improve after the final 3 day period. This means that certain adverse health effects were not improved from recovery sleep.