Lactate Dehydrogenase Activity and Insulin and Lactate Levels at an Altitude Below Sea Level (-350 m) Compared to Those at an Altitude Above Sea Level (620 m) After Exercise

F. El-Migdadi^1*, S. Y. Khatib², and N. Bashir¹

Departments of Biochemistry¹ and Physiology², School of Medicine, Jordan University of Science and Technology, P.O. Box 3030, Irbid, Jordan; fax: 962-2-295-010; E-mail: mig@just.edu.jo

^* To whom correspondence should be addressed.

Received May 6, 2000; Revision received June 26, 2000

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This study was designed to investigate the effect of exercise at 350 m below sea level altitude (-350 m) on the serum levels of lactate dehydrogenase (LDH), insulin, and lactate. The study was carried out on ten trained adult males with mean age of 23.3 ± 3.4 years following a 21-km noncompetitive run. Venous blood was withdrawn from the subjects before exercise and 5 min post exercise. For comparison purposes, a similar study was performed with the same subjects but at 620 m above sea level (+620 m). The results show a significant increase in LDH and lactate levels after exercise only at low altitude (-350 m). Serum insulin levels decreased significantly after exercise at both altitudes. These changes in serum levels of LDH, insulin, and lactate at different altitudes suggest that a type of metabolic adjustment is present that meets energy requirements during exercise.

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KEY WORDS: exercise, low altitude, lactate dehydrogenase, insulin, lactate

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