Metabolic Fatigue Research Paper

Muscle fatigue, or physical fatigue, is the decline in ability of a muscle to generate force. It can be a result of strenuous exercise but unusual fatigue may be caused by interference with the different stages of muscle contraction. There are two main causes of muscle fatigue, nervous fatigue and metabolic fatigue.
Nervous Fatigue
Nervous fatigue is the decline in the ability of a nerve to sustain a signal resulting in innervation of the muscle. The muscle's ability to generate force is most strongly limited by nerve's ability to sustain a high-frequency signal. After a period of maximum contraction, the nerve's signal reduces in frequency and the force generated by the contraction diminishes. Nerves are responsible for controlling the contraction of muscles. For extremely powerful contractions that are close to the maximum limit of a muscle's ability to produce force, nervous fatigue can be a limiting factor in untrained individuals.
Metabolic Fatigue
By contrast, metabolic fatigue is the result of a decrease in necessary ions or substrates, or the buildup of metabolites, such as lactic acid. Lactic acid accumulates as a result of anaerobic exercise, anaerobic exercise is when the exercise if focused around short powerful bursts of energy where endurance is not needed, typically requires less oxygen to perform.
It is more difficult for muscle to contract in cold temperatures than in warmer ones. Temperature affects the ease with which oxygen is released from hemoglobin. At cold temperatures, oxygen is more tightly bound to the hemoglobin and does not release as easily. This slower rate of release leads to a lower amount of oxygen available to your muscles, making contraction more difficult, this makes your muscles feel stiff. The opposite is true in warm temperatures; oxygen readily releases from hemoglobin, giving a steady supply of oxygen and allowing your muscles to contract