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.
It is known that fatigue can be caused by many different mechanisms, ranging from the accumulation of metabolites within muscle fibres to the generation of an inadequate motor command in the motor cortex, and that there is no global mechanism responsible for muscle fatigue.