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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

REFERENCES

Brouwer, E. (1965). Report of sub-committee on constants and factors. In Energy Metabolism, pp. 441–443 [Blaxter, K. L., editor]. London: Academic Press.Google Scholar
Fern, E. B. & Garlick, P. J. (1983). The rate of whole body metabolism in the whole body of man measured with 15N-glycine and uniformly labelled 15N wheat. Human Nutrition: Clinical Nutrition 37C, 91–107.Google Scholar
Fern, E. B., Garlick, P. J., McNurlan, M. A. & Waterlow, J. C. (1981). The excretion of isotope in urea and ammonia for estimating protein turnover in man with 15N-glycine. Clinical Science 61, 217–228.CrossRefGoogle Scholar
Fern, E. B., Garlick, P. J. & Waterlow, J. C. (1985 a). Apparent compartmentation of body nitrogen in one human subject: its consequences in measuring the rate of whole body protein synthesis with 15N. Clinical Science 68, 271–282.CrossRefGoogle ScholarPubMed
Fern, E. B., Garlick, P. J. & Waterlow, J. C. (1985 b). The concept of the single body pool of metabolic nitrogen in determining the rate of whole body nitrogen turnover. Human Nutrition: Clinical Nutrition 39C, 85–89.Google Scholar
Garrow, J. S. (1974). Energy Balance and Obesity in Man. Amsterdam: Elsevier and North Holland Press.Google Scholar
Grove, G. & Jackson, A. A. (1995). Measurement of protein turnover in normal man using the end-product method with oral [15N]glycine: comparison of single-dose and intermittent-dose regimens. British Journal of Nutrition 74, 491–507.CrossRefGoogle ScholarPubMed
Jeevanandam, M., Lowry, S. F., Horowitz, G. D., Legaspi, A. & Brennan, M. F. (1986).Influence of increasing dietary intake on whole body protein kinetics in normal man. Clinicai Nutrition 5, 41–48.CrossRefGoogle ScholarPubMed
Lemon, W. R. (1991). Does exercise alter dietary protein requirements? Advances in Nutrition and Top Sport 32, 15–37.Google Scholar
Millward, D. J., Botwell, J. L., Pacy, P. & Rennie, M. J. (1994). Physical activity, protein metabolism and protein requirements. Proceedings of the Nutrition Society 53, 223–240.CrossRefGoogle ScholarPubMed
Stroud, M. A. (1987). Nutrition and energy balance on the “Footsteps of Scott” expedition 1984–86. Human Nutrition: Applied Nutrition 41A, 426–433.Google Scholar
Stroud, M. A. (1993). Shadows on the Wasteland – Crossing Antarctica with Sir Ranulph Fiennes. London: Jonathan Cape.Google Scholar
Stroud, M. A., Constantin-Teodosiu, D., Coward, W. A., Greenhaff, P. L., Ritz, P. & Sawyer, M. B. (1996). Energy expenditure using isotope-labelled water (2H218O), exercise performance, skeletal muscle enzyme activities and plasma biochemical parameters in man during 95 days endurance exercise with inadequate energy intake. European Journal of Applied Physiology (In the Press).Google Scholar
Tomkins, A. M., Garlick, P. J., Schofield, W. N. & Waterlow, J. C. (1983). The combined effects of infection and malnutrition on protein metabolism in children. Clinical Science 65, 313–324.CrossRefGoogle ScholarPubMed
Waterlow, J. C. (1992). Protein-energy Malnutrition, p. 93. London: Edward Arnold.Google Scholar
Waterlow, J. C., Garlick, P. J. & Millward, D. J. (1978 a). Protein Turnover in Mammalian Tissues and in the Whole Body. Amsterdam: North Holland.Google Scholar
Waterlow, J. C., Golden, M. H. J. & Garlick, P. J. (1978 b). Protein turnover in man measured with 15N: comparison of end products and dose regimes. American Journal of Physiology 4, E165–E174.Google Scholar
Wolfe, R. R., Wole, M. H., Nadel, E. R. & Shaw, J. H. F. (1984). Isotopic determination of amino acid-urea interactions in exercise in humans. Journal of Applied Physiology 56, 221–229.CrossRefGoogle ScholarPubMed