PHYSIOLOGY
MUSCLE FATIGUE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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inadequate numbers of mitochondria.
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insufficient intracellular quantities of ATP due to excessive consumption.
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decreased levels of lactic acid.
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increase levels of carbon dioxide in cells.
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Detailed explanation-1: -Muscle fatigue has a number of possible causes including impaired blood flow, ion imbalance within the muscle, nervous fatigue, loss of desire to continue, and most importantly, the accumulation of lactic acid in the muscle.
Detailed explanation-2: -Fatigue often develops when substrates for ATP generation are depleted and/or when metabolic by-products accumulate in contracting muscle and the blood. Reductions in intramuscular levels of ATP, phosphocreatine and glycogen, and low blood glucose (hypoglycemia) can impair skeletal muscle performance.
Detailed explanation-3: -ATP is critical for muscle contractions because it breaks the myosin-actin cross-bridge, freeing the myosin for the next contraction.
Detailed explanation-4: -Glycolysis converts glucose to pyruvate, water and NADH, producing two molecules of ATP. Excess pyruvate is converted to lactic acid which causes muscle fatigue.