THE EFFECT OF DEHYDRATION ON WRESTLING MINIMUM WEIGHT ASSESSMENT.
Given that some wrestlers arrive for minimum weight (MW) testing in a dehydrated condition, it is important to understand the effects of dehydration
HEAT TOLERANCE AND ACCLIMATIZATION TO WORK IN THE HEAT IN RELATION TO AGE.
No abstract available.
Recent advances in the understanding of water metabolism in heart failure.
Hyponatremia is common in advanced heart failure and relates to the severity of the disease. Non-osmotic arginine vasopressin (AVP) release and biosynthesis have been shown to be increased during chronic cardiac failure (CHF) and baroreceptors pathways have been demonstrated to play a major role in this non-osmotic stimulation of AVP. Decreased cardiac output unloads the [...]
The clinical physiology of water metabolism. Part III: The water depletion (hyperosmolar) and water excess (hyposmolar) syndromes.
Hyperosmolality occurs when there are defects in the two major homeostatic mechanisms required for water balance-thirst and arginine vasopressin (AVP) release. In this situation hypotonic fluids are lost in substantial quantities causing depletion of both intracellular and extracellular fluid compartments. Patients with essential hypernatremia have defective osmotically stimulated AVP release and thirst but may have [...]
DEHYDRATION ENHANCES ENDOTOXIN FEVER BY INCREASED PRODUCTION OF ENDOGENOUS PYROGEN
The febrile responses in rats to an intravenous injection of the bacterial endotoxin Salmonella typhosa were investigated under normally hydrated and dehydrated conditions. When endotoxin was injected intravenously into the dehydrated rats, a biphasic-patterned fever resulted, whereas in normal rats an intravenous injection of endotoxin did not induce fever. No significant differences in febrile responses [...]
Electrolyte & water metabolism in sports activities.
Few studies in water and electrolyte metabolism during sports activities have directed attention to magnesium. Addition of magnesium to sports beverages in appropriate concentrations appears to be safe. This article considers the potential role and availability of magnesium in fluid repletion during sports activities
The clinical physiology of water metabolism. Part II: Renal mechanisms for urinary concentration; diabetes insipidus.
The renal reabsorption of water independent of solute is the result of the coordinated function of the collecting duct and the ascending limb of the loop of Henle. The unique juxtaposition of the ascending and descending portions of the loop of Henle and of the vasa recta permits the function of a counter-current multiplier system [...]
HYPOHYDRATION EFFECT ON FINGER SKIN TEMPERATURE AND BLOOD FLOW DURING COLD-WATER FINGER IMMERSION
This study was conducted to determine whether hypohydration (Hy) alters blood flow, skin temperature, or cold-induced vasodilation (CIVD) during peripheral cooling. Fourteen subjects sat in a thermoneutral environment (27 degrees C) during 15-min warm-water (42 degrees C) and 30-min cold-water (4 degrees C) finger immersion (FI) while euhydrated (Eu) and, again, during Hy. Hy (-4% [...]
Abnormalities of water metabolism in the elderly.
Hypernatremia is a frequent problem at the extremes of age, but particularly so in elderly individuals. Changes in the physiological responses to water deprivation with increasing age may be of particular interest in understanding the pathogenesis of hypernatremia in the elderly. When comparing healthy elderly men to younger controls, there are differences in the response [...]
The clinical physiology of water metabolism. Part I: The physiologic regulation of arginine vasopressin secretion and thirst.
Water balance is tightly regulated within a tolerance of less than 1 percent by a physiologic control system located in the hypothalamus. Body water homeostasis is achieved by balancing renal and nonrenal water losses with appropriate water intake. The major stimulus to thirst is increased osmolality of body fluids as perceived by osmoreceptors in the [...]