(1) Accumulation of lactic acid results in muscular pain.
(2) During 100 m race a well trained athlete can hold his breath and afterwards he pants.
(3) In this case, the muscles are using energy released during the anaerobic break down of glucose, lactic acid is produced.
(4) The presence of lactic acid in the blood is the main cause of muscle fatigue. Whether it is 100 mtr race or 5 km race.
(5) If the body is rested long enough the tiredness goes.
