Alertness and sleep in young men during military service

Alertness and sleep in healthy young men conscripted into military service were examined by testing personality characteristics and by completing questionnaires at the beginning of military service about their civilian life alertness and sleep, and by using polygraphic recordings during their military service. Sleep-time during service was restricted to 8 hours a night; 236 men answered the questionnaire on civilian life alertness and sleep; 116 men a Minnesota multiphasic personality inventory; 7 underwent conventional, and 29 static charge-sensitive bed sleep recordings. Daytime latencies to Stage 2 sleep were 11 +/- 2 min. Sleep latencies were the shortest 6 h after waking. Night sleep was normal in conventional recordings. Nocturnal activities in static charge-sensitive bed recordings were: motor-active waking 4 +/- 3%, active sleep 24 +/- 11%, intermediate sleep 22 +/- 8%, quiet sleep 47 +/- 13%, and undefined 4 +/- 2%. Positive answers to questions on civilian life sleepiness were related to high scores on scales for hypochondria, psychasthenia and sense of reality, and night sleep longer than 10 h to high scores for psychasthenia and sense of reality, but not to polygraphic measures. Two men with complaints about civil-time irresistible sleep at the time of beginning the military service had short Stage 2 latencies at the daytime minimum of alertness during service (4 and 8 min). Although alertness and sleep during military service were normal on average, the findings suggest that all conscripted individuals may not have had enough sleep.