In 1979, Pol Pot and the Khmer Rouge were forced from power by the invading Vietnamese. Pol Pot officially resigned the leadership in 1985 but appears to have retained considerable influence.
Muscle fatigue. Muscle fatigue is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction.
1 Not enough sleep or disruptions to the sleep-wake cycle (such as those that may occur with shift work or travelling to a different time zone) cause the physiological state known as fatigue.  Staying awake for 24 hours leads to a reduced hand-to-eye coordination that is similar to having a blood alcohol content of 0.1.