Skip to main content
PMC home page
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1972 Feb;51(2):242–255. doi: 10.1172/JCI106809

Pathophysiology of Intense Physical Conditioning in a Hot Climate. I. MECHANISMS OF POTASSIUM DEPLETION

James P Knochel 1, Larry N Dotin 1, Richard J Hamburger 1
PMCID: PMC302122  PMID: 5009112

Abstract

Serial estimations of exchangeable 42K showed that six volunteer subjects undergoing intensive physical conditioning in a hot climate sustained a mean deficit of 517 mEq. This deficit occurred despite a daily potassium intake of 100 mEq. Simultaneous values for lean body mass rose suggesting that potassium deficiency was not the result of catabolism. Although sweating was the major avenue by which the deficit occurred, daily excretion of potassium into the urine when each subject was maximally deficient ranged from 46 to 75 mEq and thus was inappropriately high for potassium-depleted subjects. Despite high intakes of sodium and excretion of corresponding quantities into the urine, Na/K ratios in sweat were low thus indicating unsuppressed activity of aldosterone on sweat glands. Moreover, excretion and secretion of aldosterone and in many instances, plasma renin activity, appeared to be high with respect to sodium intake.

These findings suggest that intense physical work in the heat stimulates higher production of aldosterone than would occur in nonexercising subjects on similar sodium intakes. Similar to the phenomenon of mineralocorticoid escape, such overproduction of aldosterone in the presence of conditions permitting excretion of sodium into the urine could facilitate continued excretion of potassium by the kidney despite serious potassium depletion. As a consequence, the kidney played a role in the genesis of potassium depletion in these subjects.

In contrast to subjects undergoing conditioning in the summer months, potassium depletion did not occur in 16 subjects during identical training under cooler environmental conditions.

Full text

PDF

Images in this article

252Image
on p.252

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BERNSTEIN L., INOYE T., PASCAL L. R., RYAN R. J. Experiences with radiosulfate in the estimation of physiologic extracellular water in healthy and abnormal man. J Clin Invest. 1956 Oct;35(10):1119–1130. doi: 10.1172/JCI103366. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. BOUCHER R., VEYRAT R., DE CHAMPLAIN J., GENEST J. NEW PROCEDURES FOR MEASUREMENT OF HUMAN PLASMA ANGIOTENSIN AND RENIN ACTIVITY LEVELS. Can Med Assoc J. 1964 Jan 25;90:194–201. [PMC free article] [PubMed] [Google Scholar]
  3. Beisel W. R., Goldman R. F., Joy R. J. Metabolic balance studies during induced hyperthermia in man. J Appl Physiol. 1968 Jan;24(1):1–10. doi: 10.1152/jappl.1968.24.1.1. [DOI] [PubMed] [Google Scholar]
  4. Biglieri E. G., McIlroy M. B. Abnormalities of renal function and circulatory reflexes in primary aldosteronism. Circulation. 1966 Jan;33(1):78–86. doi: 10.1161/01.cir.33.1.78. [DOI] [PubMed] [Google Scholar]
  5. Braun W. E., Maher J. T., Byrom R. F. Effect of exogenous d-aldosterone on heat acclimatization in man. J Appl Physiol. 1967 Sep;23(3):341–346. doi: 10.1152/jappl.1967.23.3.341. [DOI] [PubMed] [Google Scholar]
  6. CAMARGO C. A., DOWDY A. J., HANCOCK E. W., LUETSCHER J. A. DECREASED PLASMA CLEARANCE AND HEPATIC EXTRACTION OF ALDOSTERONE IN PATIENTS WITH HEART FAILURE. J Clin Invest. 1965 Mar;44:356–365. doi: 10.1172/JCI105149. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. CONN J. W. Aldosteronism in man. Some clinical and climatological aspects. I. JAMA. 1963 Mar 2;183:775–781. [PubMed] [Google Scholar]
  8. COPPAGE W. S., Jr, ISLAND D. P., COONER A. E., LIDDLE G. W. The metabolism of aldosterone in normal subjects and in patients with hepatic cirrhosis. J Clin Invest. 1962 Aug;41:1672–1680. doi: 10.1172/JCI104624. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. CORSA L., Jr, OLNEY J. M., Jr, STEENBURG R. W., BALL M. R., MOORE F. D. The measurement of exchangeable potassium in man by isotope dilution. J Clin Invest. 1950 Oct;29(10):1280–1295. doi: 10.1172/JCI102365. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. COTLOVE E., TRANTHAM H. V., BOWMAN R. L. An instrument and method for automatic, rapid, accurate, and sensitive titration of chloride in biologic samples. J Lab Clin Med. 1958 Mar;51(3):461–468. [PubMed] [Google Scholar]
  11. Cannon P. J., Ames R. P., Laragh J. H. Relation between potassium balance and aldosterone secretion in normal subjects and in patients with hypertensive or renal tubular disease. J Clin Invest. 1966 Jun;45(6):865–879. doi: 10.1172/JCI105402. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Cohen E. L., Conn J. W., Rovner D. R. Postural augmentation of plasma renin activity and aldosterone excretion in normal people. J Clin Invest. 1967 Mar;46(3):418–428. doi: 10.1172/JCI105543. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Collins K. J. The action of exogenous aldosterone on the secretion and composition of drug-induced sweat. Clin Sci. 1966 Apr;30(2):207–221. [PubMed] [Google Scholar]
  14. Collins K. J., Weiner J. S. Endocrinological aspects of exposure to high environmental temperatures. Physiol Rev. 1968 Oct;48(4):785–839. doi: 10.1152/physrev.1968.48.4.785. [DOI] [PubMed] [Google Scholar]
  15. Collins R. D., Weinberger M. H., Dowdy A. J., Nokes G. W., Gonzales C. M., Luetscher J. A. Abnormally sustained aldosterone secretion during salt loading in patients with various forms of benign hypertension; relation to plasma renin activity. J Clin Invest. 1970 Jul;49(7):1415–1426. doi: 10.1172/JCI106359. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Darling R. C., Cournand A., Richards D. W. STUDIES ON THE INTRAPULMONARY MIXTURE OF GASES. III. AN OPEN CIRCUIT METHOD FOR MEASURING RESIDUAL AIR. J Clin Invest. 1940 Jul;19(4):609–618. doi: 10.1172/JCI101163. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Espiner E. A., Tucci J. R., Jagger P. I., Lauler D. P. Effect of saline infusions on aldosterone secretion and electrolyte excretion in normal subjects and patients with primary aldosteronism. N Engl J Med. 1967 Jul 6;277(1):1–7. doi: 10.1056/NEJM196707062770101. [DOI] [PubMed] [Google Scholar]
  18. FLEAR C. T., COOKE W. T., QUINTON A. Serum-potassium levels as an index of body content. Lancet. 1957 Mar 2;272(6966):458–459. doi: 10.1016/s0140-6736(57)90525-1. [DOI] [PubMed] [Google Scholar]
  19. FUKUCHI S., HANATA M., TAKAHASHI H., DEMURA H., GOTO K. THE RELATIONSHIP BETWEEN VASCULAR REACTIVITY AND EXTRACELLULAR POTASSIUM. Tohoku J Exp Med. 1965 Mar 25;85:181–191. doi: 10.1620/tjem.85.181. [DOI] [PubMed] [Google Scholar]
  20. GANN D. S., DELEA C. S., GILL J. R., Jr, THOMAS J. P., BARTTER F. C. CONTROL OF ALDOSTERONE SECRETION BY CHANGE OF BODY POTASSIUM IN NORMAL MAN. Am J Physiol. 1964 Jul;207:104–108. doi: 10.1152/ajplegacy.1964.207.1.104. [DOI] [PubMed] [Google Scholar]
  21. Gordon R. S., Jr, Andrews H. L. Potassium depletion under heat stress. Fed Proc. 1966 Jul-Aug;25(4):1372–1374. [PubMed] [Google Scholar]
  22. Gross E. G., Dexter J. D., Roth R. G. Hypokalemic myopathy with myoglobinuria associated with licorice ingestion. N Engl J Med. 1966 Mar 17;274(11):602–606. doi: 10.1056/NEJM196603172741104. [DOI] [PubMed] [Google Scholar]
  23. HUTH E. J., SQUIRES R. D., ELKINTON J. R. Experimental potassium depletion in normal human subjects. II. Renal and hormonal factors in the development of extracellular alkalosis during depletion. J Clin Invest. 1959 Jul;38(7):1149–1165. doi: 10.1172/JCI103891. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Jenkins M. E., Rivarola M. A., Brusilow S. W., Migeon C. J. Excretion of 4-14C-cortisol and 1,2-3H-D-aldosterone in human thermal sweat. J Clin Endocrinol Metab. 1969 Aug;29(8):1102–1106. doi: 10.1210/jcem-29-8-1102. [DOI] [PubMed] [Google Scholar]
  25. KLIMAN B., PETERSON R. E. Double isotope derivative assay of aldosterone in biological extracts. J Biol Chem. 1960 Jun;235:1639–1648. [PubMed] [Google Scholar]
  26. KNOCHEL J. P., BEISEL W. R., HERNDON E. G., Jr, GERARD E. S., BARRY K. G. The renal, cardiovascular, hematologic and serum electrolyte abnormalities of heat stroke. Am J Med. 1961 Feb;30:299–309. doi: 10.1016/0002-9343(61)90101-2. [DOI] [PubMed] [Google Scholar]
  27. Kassirer J. P., Schwartz W. B. Correction of metabolic alkalosis in man without repair of potassium deficiency. A re-evaluation of the role of potassium. Am J Med. 1966 Jan;40(1):19–26. doi: 10.1016/0002-9343(66)90183-5. [DOI] [PubMed] [Google Scholar]
  28. Knochel J. P., Vertel R. M. Salt loading as a possible factor in the production of potassium depletion, rhabdomyolysis, and heat injury. Lancet. 1967 Mar 25;1(7491):659–661. doi: 10.1016/s0140-6736(67)92547-0. [DOI] [PubMed] [Google Scholar]
  29. Krzywicki H. J., Chinn K. S. Human body density and fat of an adult male population as measured by water displacement. Am J Clin Nutr. 1967 Apr;20(4):305–310. doi: 10.1093/ajcn/20.4.305. [DOI] [PubMed] [Google Scholar]
  30. LIND A. R., BASS D. E. Optimal exposure time for development of acclimatization to heat. Fed Proc. 1963 May-Jun;22:704–708. [PubMed] [Google Scholar]
  31. LUETSCHER J. A., DOWDY A. J., CALLAGHAN A. M., COHN A. P. Studies of secretion and metabolism of aldosterone and cortisol. Trans Assoc Am Physicians. 1962;75:293–300. [PubMed] [Google Scholar]
  32. MOORE F. D., EDELMAN I. S., OLNEY J. M., JAMES A. H., BROOKS L., WILSON G. M. Body sodium and potassium. III. Interrelated trends in alimentary, renal and cardiovascular disease; lack of correlation between body stores and plasma concentration. Metabolism. 1954 Jul;3(4):334–350. [PubMed] [Google Scholar]
  33. Mohamed S. D., Chapman R. S., Crooks J. Hypokalaemia, flaccid quadruparesis, and myoglobinuria with carbenoxolone (biogastrone). Br Med J. 1966 Jun 25;1(5503):1581–1582. doi: 10.1136/bmj.1.5503.1581. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. PRENTICE T. C., SIRI W., BERLIN N. I., HYDE G. M., PARSONS R. J., JOINER E. E., LAWRENCE J. H. Studies of total body water with tritium. J Clin Invest. 1952 Apr;31(4):412–418. doi: 10.1172/JCI102624. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Pickens P. T., Bumpus F. M., Lloyd A. M., Smeby R. R., Page I. H. Measurement of renin activity in human plasma. Circ Res. 1965 Nov;17(5):438–448. doi: 10.1161/01.res.17.5.438. [DOI] [PubMed] [Google Scholar]
  36. ROBINSON S., ROBINSON A. H. Chemical composition of sweat. Physiol Rev. 1954 Apr;34(2):202–220. doi: 10.1152/physrev.1954.34.2.202. [DOI] [PubMed] [Google Scholar]
  37. ROBINSON S., ROBINSON A. H. Chemical composition of sweat. Physiol Rev. 1954 Apr;34(2):202–220. doi: 10.1152/physrev.1954.34.2.202. [DOI] [PubMed] [Google Scholar]
  38. ROSS E. J., REDDY W. J., RIVERA A., THORN G. W. Effects of intravenous infusions of dl-aldosterone acetate on sodium and potassium excretion in man. J Clin Endocrinol Metab. 1959 Mar;19(3):289–296. doi: 10.1210/jcem-19-3-289. [DOI] [PubMed] [Google Scholar]
  39. SCHWARTZ I. L., THAYSEN J. H. Excretion of sodium and potassium in human sweat. J Clin Invest. 1956 Jan;35(1):114–120. doi: 10.1172/JCI103245. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. SCHWARTZ I. L., THAYSEN J. H. Excretion of sodium and potassium in human sweat. J Clin Invest. 1956 Jan;35(1):114–120. doi: 10.1172/JCI103245. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Schrier R. W., Hano J., Keller H. I., Finkel R. M., Gilliland P. F., Cirksena W. J., Teschan P. E. Renal, metabolic, and circulatory responses to heat and exercise. Studies in military recruits during summer training, with implications for acute renal failure. Ann Intern Med. 1970 Aug;73(2):213–223. doi: 10.7326/0003-4819-73-2-213. [DOI] [PubMed] [Google Scholar]
  42. Shibolet S., Coll R., Gilat T., Sohar E. Heatstroke: its clinical picture and mechanism in 36 cases. Q J Med. 1967 Oct;36(144):525–548. [PubMed] [Google Scholar]
  43. Streeten D. H., Schletter F. E., Clift G. V., Stevenson C. T., Dalakos T. G. Studies of the renin-angiotensin-aldosterone system in patients with hypertension and in normal subjects. Am J Med. 1969 Jun;46(6):844–861. doi: 10.1016/0002-9343(69)90086-2. [DOI] [PubMed] [Google Scholar]
  44. ULLRICK W. C., HAZELWOOD R. L. Influence of aldosterone on isometric tension development in the rat heart. Am J Physiol. 1963 Jun;204:1001–1004. doi: 10.1152/ajplegacy.1963.204.6.1001. [DOI] [PubMed] [Google Scholar]
  45. Vertel R. M., Knochel J. P. Acute renal failure due to heat injury. An analysis of ten cases associated with a high incidence of myoglobinuria. Am J Med. 1967 Sep;43(3):435–451. doi: 10.1016/0002-9343(67)90196-9. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation

RESOURCES