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Protein turnover rates of two human subjects during an unassisted crossing of Antarctica

Published online by Cambridge University Press:  09 March 2007

M. A. Stroud ,
A. A. Jackson  and
J. C. Waterlow
M. A. Stroud
Affiliation:
Institute of Human Nutrition, West Wing Level C, Southampton General Hospital, Tremona Road, Southampton S09 4XY
A. A. Jackson
Affiliation:
Institute of Human Nutrition, West Wing Level C, Southampton General Hospital, Tremona Road, Southampton S09 4XY
J. C. Waterlow
Affiliation:
London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT
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Abstract

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During the Austral summer of 1992–3, two men, MS and RF, walked 2300 km across Antarctica in 96 d, unassisted by other men, animals or machines. During the journey they ate freeze-dried rations, towed on sledges, that contained an average of 21·3 MJ/d of which 56·7% was fat, 35·5% carbohydrate and 7·8% protein (98·8 g). Despite this high energy intake both men lost more than 20 kg in body weight due to their extremely high energy expenditures. Studies of protein turnover using [15N]glycine by the single-dose end-product method were made before, during and after the journey, and these demonstrated considerable differences in the metabolic responses of the two men to the combined stresses of exercise, cold and undernutrition. However, both men maintained high and relatively stable levels of protein synthesis during the expedition despite the great exertion and the onset of considerable debilitation. This stability indicates the vital physiological function of protein synthesis.

Keywords

Protein turnoverExerciseUndernutrition
Type
Human and Clinical Nutrition
Information
British Journal of Nutrition , Volume 76 , Issue 2 , August 1996 , pp. 165 - 174
Copyright
Copyright © The Nutrition Society 1996

References

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