text: Chapter 11
  BEHAVIORAL FACTORS
  11-62. In addition to operational requirements, sleep readiness also depends on the behavior of individual
  Soldiers. The conditions in which Soldiers find themselves, as well as the schedules they maintain or
  activities in which they participate, contribute to sleep readiness.
  Exercise
  11-63. Regular, moderate physical exercise facilitates subsequent nighttime sleep onset and promotes
  deeper (more restorative) sleep. However, vigorous exercise immediately prior to bedtime can interfere with
  sleep for some individuals, especially if that exercise is to exhaustion, producing a physiological stress
  response. During the daytime, short bouts of around 30 minutes of physical activity can result in a moderate
  3-hour boost of alertness in well-rested Soldiers. Such bouts do little for reversing and sustaining alertness
  under conditions of significant sleep loss.
  Diet
  11-64. Various foods and food preparation techniques can affect sleep—both positively and negatively.
  Sleep-promoting foods tend to be high in fiber and low in added sugars. High-fat, fried, or spicy foods tend
  to negatively impact sleep. Such foods tax the stomach, are difficult to digest, and may cause nocturnal
  esophageal reflux or heartburn. Soldiers should avoid these types of foods prior to bedtime. As a rule, Soldiers
  should avoid full, heavy meals within 2–3 hours of initiating sleep. However, they should not go to bed
  hungry either, since hunger can also lighten and disrupt sleep. If Soldiers need to eat just prior to bedtime,
  their best options include a balanced snack or meal that includes fruits; vegetables; whole grains; fat proteins;
  and foods low in added sugar. Foods that rarely disturb sleep include Greek yogurt or cottage cheese with
  fruit, peanut butter on whole grain toast, cheese and crackers, milk with a small bowl of whole grain cereal,
  and protein bars.
  Alcohol
  11-65. Although alcohol increases drowsiness and can facilitate sleep onset, it subsequently lightens and
  disrupts sleep as the body metabolizes it during the night. It causes multiple arousals and awakenings, thus
  harming sleep more than it helps. The body metabolizes alcohol at a rate of about one ounce per hour.
  Therefore, to avoid the negative effects of alcohol on sleep, Soldiers should consume no more than one drink
  one hour before bedtime, no more than two drinks two hours before bedtime, and so on. However, abstinence
  is the best strategy when a good night of sleep is especially important for next-day activities or missions.
  Sleep Environment
  11-66. The importance of a sleep-friendly environment cannot be overstated. Living conditions and
  environments vary widely, but leaders can improve most sleep areas with a few simple steps.
  Ambient Noise
  11-67. Sleeping quarters should be located as far away from noisy areas (such as airfields, generators, and
  fueling stations) as possible. The effects of remaining uncontrollable, intermittent, random noises should be
  masked with a white noise generator. Finally, Soldiers can wear noise-dampening earplugs to effectively
  block noise and improve sleep.
  Physical Comfort
  11-68. Room temperature should be cool, ranging from 65–72 ºF. Sheets, bed, pillows, sleep surfaces (such
  as mattresses and cots), and sleeping clothes should be clean and comfortable. Mattresses should be
  requisitioned to fit the Soldier.
  Light
  11-69. Humans are not nocturnal. Soldiers are hardwired to be active during the day and to sleep at night.
  The brain’s internal clock is very sensitive to light, and any amount of light that reaches the brain through