Question

Feeling of fatigue after running fast for some time is due to
(a) Loss of energy.
(b) Accumulation of lactic acid in muscles.
(c) Formation of succinic acid.
(d) Formation of biuret crystals.

Answer 1

Hint: After doing an extra physical activity we feel fatigued or exhausted. This happens due to an acid that gets mixed up with the fluid and results in a lack of oxygen.

Complete answer:
After running fast for some time we feel fatigued due to the accumulation of lactic acid in muscles. Generally, the glucose undergoes metabolism in the presence of oxygen to form ATP or adenosine triphosphate which is essential for the muscle contraction but during vigorous exercise, the body cannot meet the oxygen demand and the glucose undergoes metabolism in the absence of oxygen which results in the formation and accumulation of lactic acid.
So, the correct answer is 'Accumulation of lactic acid in muscles'.

Additional Information:
- Even if it's only for a few minutes at a time, your muscles will thank you. Stretching can help to stimulate circulation, increase flexibility, and relieve tension.
- This helps bring more oxygen to your muscles, which can reduce lactic acid production and rid your muscles of any accumulation of lactic acid.
- Lactic acid is taken to the liver by the blood, and either: oxidized to carbon dioxide and water, or converted to glucose, then glycogen - glycogen levels in the liver and muscles can then be restored. These processes require oxygen. This is why, when the period of activity is over, a person’s breathing rate and heart rate do not return to normal straight away.

Note:
- Lactic acid is processed by the liver and the heart. The liver converts it back into sugar; the heart converts it into pyruvate.
- During exercise, concentrations of lactic acid in the body do spike because the heart and liver can't deal with the waste product as quickly as it's produced. But as soon as we're done exercising, lactic acid concentrations go back to normal, Gleeson said.
- When a period of exercise is over, lactic acid must be removed. The body's tolerance for lactic acid is limited.