ULTRA-SHORT WORK IS AEROBIC
Astrand, I., Astrand, P-O., Christensen, E. H., & Hedman, R. (1960). Myohemoglobin as an oxygen-store in man. Acta Physiologica Scandinavica, 48, 454-460.
This study investigated further the possible role of myohemoglobin as an oxygen-store during the initial stage of muscular work. One subject worked intermittently on a bicycle ergometer with a work load of 2,520 kpm/min with varied duration of work and rest pauses. A significant difference in the blood lactic acid concentration during the experimental time of 30 minutes was found in work with short work periods (10 sec, lactic acid concentration about 10-20 mg per 100 ml) compared to relatively long ones (60 sec, lactic acid concentration 110-140 mg per 100 ml). It was concluded that the short type of work was performed aerobically. The calculated oxygen demand, during the work period of 10 sec, however, did not correspond to the measured oxygen intake. A deficit of about 0.43 L 02 for each period of work occurred. It was suggested that the amount of 0.43 L 02 is supplied to the working muscle mainly from oxymyohemoglobin. This store function of myohemoglobin is discussed in relation to the present findings and to the results mentioned in the literature.
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