Fatigue, is the final frontier in our modern too-busy lives. No, seriously, from that threshold nothing is achieved, nothing improved and nothing is gained. Only problems ensue.
[code]Definition: “Fatigue is a condition characterized by increased discomfort with lessened capacity for work, reduced efficiency of accomplishment, loss of power or capacity to respond to stimulation, and is usually accompanied by a feeling of weariness and tiredness.”[/code]
It is a burnout, or feeling tired…minor change in mood, energy, or sleep; the lowest reaches of wellness. Fatigue is a symptom of your brain reaching a point of dysfunction…a large spectrum of dysfunction. The spectrum ranges from momentary blips on the radar of simply needing a break, a catnap for instance, or needing to eat lunch, to more severe, devastating, life-altering, neurodegenerative disorders of complete exhaustion…Yikes!

There are two kinds of Fatigue:  Acute (short-term) and Chronic (long-term).  Short term acute fatigue is easily cured by a sound sleep and is a normal daily occurrence. The chronic fatigue however has deeper psychological roots and causes significant psychosomatic ailments, which can lead to long term disability from debilitation. Some of these include: tiredness, heart palpitations, breathlessness, headaches, or irritability. Sometimes chronic fatigue even creates stomach or intestinal problems and generalized aches and pains throughout the body and even depression. Self-help cures in these circumstances are rare.

Above all, when in the throes of chronic stress, don’t fly!
Let’s look at some of the common issues encountered: sleepiness, difficulty concentrating, apathy, feelings of isolation, annoyance, increased reaction time to stimulus, slowing of higher-level mental functioning, decreased vigilance, memory problems, task fixation, and increased errors while performing tasks.

Fatigued individuals consistently underreport how tired they are, as measured by physiologic parameters. No degree of experience, motivation, medication, coffee, other stimulants, or will power can overcome fatigue. Nine hours into his 33-hour flight, Charles Lindbergh wrote in his journal that, “…nothing life can attain, is quite so desirable as sleep.”
A special kind of fatigue that can afflict a pilot with profound ramifications is “Skill Fatigue.” Skill Fatigue involves two main disruptions:

• Timing disruption – Performing a task as usual, but with the timing of each component is slightly off, makes the pattern of the operation less smooth and fluid. There is a higher chance of disruption in finishing the task.
• Disruption of the perceptual field – You concentrate your attention upon movements or objects in the center of your vision and neglect those in the periphery. This leads to loss of accuracy and smoothness in control movements. The effects are magnified in high task saturated environments eg. turbulent weather in instrument conditions.

Other symptoms include: memory fog (where did I leave my keys), difficulty following instructions, lowered retention, lack of motivation, tire easily, poor focus, emotional meltdown and psychosomatic pains and digestive complaints. And while it is felt in the peripheral muscles as weakness it is a central dogma arising in the brain; Brain (Central Governance Model-CGM) generates the sensations of fatigue during exercise (MIND OVER MATTER) – Fatigue is a Brain-Derived Emotion that Regulates the Exercise Behavior to Ensure the Protection of Whole Body Homeostasis. ( Timothy David Noakes,* Front Physiol. 2012; 3: 8)  While initially fatigue causes a reduction in muscular force, the brain executes a second phenomenon of fatigue as a sensation. The central psychical station influencing the peripheral muscular network might appear as an imperfection, yet it is an extraordinary perfection of support and self-preservation.

Imaging brain fatigue from sustained mental workload: An ASL perfusion study of the time-on-task effect. Julian Lim et.al. NeuroImage 49 (2010) 3426–3435

Fatigue as a phenomenon has been extensively studied by the FAA in Commercial Pilots flying over multiple time zones and the Rules require mandatory rests crossing over 4 time zones and 8/9 accumulated flight hours. (Prevalence of fatigue among commercial pilots Craig A. Jackson 1 and Laurie Earl 2 Occup Med (Lond) (June 2006) 56(4): 263-268.)

The current regulations are:
[code]“The new regulations, which don’t apply to cargo pilots, require that pilots get at least 10 hours of rest between shifts. Eight of those hours must involve uninterrupted sleep. In the past, pilots could spend those eight hours getting to and from the hotel, showering and eating. Pilots will be limited to flying eight or nine hours, depending on their start times. They must also have 30 consecutive hours of rest each week, a 25% increase over previous requirements.”[/code]
We must remember that the ultimate risk of pilot fatigue is an aircraft accident and potential fatalities, such as the Colgan Air Crash that occurred in early 2009 (http://aviation.about.com/od/Accidents/a/Accident-Profile-Colgan-Air-Continental-Connection-Flight-3407.htm)

What is the ultimate antidote to Fatigue?  Answer: SLEEP.
Here are some Dos and Don’ts for pilots and surely-bonded- land-lubbers to live by:

Do…

1. Be mindful of the side effects of certain medications, even over-the-counter medications – where drowsiness or impaired alertness is a concern.
2. Consult a physician to diagnose and treat any medical conditions causing sleep problems.
3. Create a comfortable sleep environment at home. Adjust heating and cooling as needed. Get a comfortable mattress.
4. When traveling, select hotels that provide a comfortable environment.
5. Get into the habit of sleeping eight hours per night. When needed, and if possible, nap during the day, but limit the nap to less than 30 minutes. Longer naps produce sleep inertia, which is counterproductive. 6. Try to turn in at the same time each day. This establishes a routine and helps you fall asleep quicker.
6. If you can’t fall asleep within 30 minutes of going to bed, get up and try an activity that helps induce sleep (watch non-violent TV, read, listen to relaxing music, etc).
7. Get plenty of rest and minimize stress before a flight. If problems preclude a good night’s sleep, rethink the flight and postpone it accordingly.

Don’t…

1. Consume alcohol or caffeine 3-4 hours before going to bed.
2. Eat a heavy meal just before bedtime.
3. Take work to bed.
4. Exercise 2-3 hours before bedtime. While working out promotes a healthy lifestyle, it shouldn’t be done too close to bedtime.
5. Use sleeping pills (prescription or otherwise).

Fatigue is a slow inebriation of senses and its harm lies menacingly in the wings. Early recognition and prevention is the key to flight safety!

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