Article Text

PDF

Exercise-induced changes in urinary water and mineral output during the menstrual cycle.
  1. D N Prashad,
  2. P A Fletcher,
  3. M Cooper

    Abstract

    This study monitors changes in urinary excretion of water and minerals before and after exercise in pre-menopausal women and in those using oral contraception. Resting urine flow rate was lower and sodium output significantly higher (p less than 0.02) during the normal post-menstrual phase than during other phases of the cycle. These changes were unrelated to glomerular filtration rate and might impede maximal performance. After exercise an oliguria and hyponatriuresis were most pronounced during the menstrual phase. In addition the resting urinary output of calcium and magnesium were unrelated to normal oestrogenic and progestegenic cyclic surges. Amongst oral contraceptive users, resting excretion of water, minerals and creatinine were all significantly lower than general menstrual cycle values (p less than 0.01) and further reductions in salts and water output occurred with exercise. Basal calcium and magnesium excretion rates were significantly lower than general menstrual cycle values (p less than 0.05). Renal conservation of water and salts for 'pill' takers may affect renal homeostasis. The consequences of mineral retention are unknown.

    Statistics from Altmetric.com

    Request permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.