Disorders of serum sodium occur commonly in athletes participating in endurance sports. The most life-threatening of these is hyponatremia, which can occur in as many as 2% to 7% of participants. Exercise-associated hyponatremia (EAH) is caused by a combination of excessive water or hypotonic fluid intake as well as high levels of arginine vasopressin, which [...]
The increase in body water during pregnancy is responsible for the largest portion of weight gain and is of interest of clinical practitioners. However, assessing changes in body fluids is not easily accomplished during pregnancy. The purpose of this study was to examine the accuracy of bioelectrical impedance spectroscopy for estimating fluid volumes before, during, [...]
The Institute of Medicine expressed a need for improved sweating rate (msw) prediction models that calculate hourly and daily water needs based on metabolic rate, clothing, and environment. More than 25 years ago, the original Shapiro prediction equation (OSE) was formulated as msw (g.m(-2).h(-1))=27.9.Ereq.(Emax)(-0.455), where Ereq is required evaporative heat loss and Emax is maximum [...]
No abstract available.
Dehydration is typical during prolonged exercise. Because training stimulates numerous adaptations, some involving fluid regulation, it is conceivable that training involves adaptations to dehydration. This study tested the hypothesis that trained individuals have altered fluid regulatory, but not behavioural or perceptual responses to exercise when hypohydrated. Six trained (V.O2 peak: 65 ± 8 mL kg− [...]
No abstract available.
Body weight, resting metabolic rate (RMR), total body potassium (TBK), and total body water were measured and total body fat (TBF) was calculated in a longitudinal study of 22 pregnant, healthy Swedish women. Measurements were made before pregnancy, at gestational weeks 16-18, 30, and 36, and 5-10 d and 6 mo postpartum. RMR increased more [...]
PURPOSE: The purpose of this study was to determine a quick and easy method for assessment of day-to-day hydration status in athletes in the heat. METHODS: Measurement of the osmolality of the first urine sample of the day collected after wakening but before breakfast established a standardized collection procedure to allow day-to-day comparisons of individuals. [...]
The purpose of this study was to assess sweat loss and hydration practices of elite female field hockey players during consecutive international matches. Eighteen England U21 field hockey players were assessed during 2 consecutive international matches. Sweat loss was assessed from changes in body mass after correction for the volume of fluid consumed and any [...]
PURPOSE: To determine whether athletes who had previously developed hyponatremia during an ultradistance triathlon show an impaired ability to excrete a large fluid load compared with athletes who had completed the same race without developing hyponatremia. METHODS: Six athletes who had developed hyponatremia ([Na] < 135 mmol x L(-1)) in the 1997 Ironman Triathlon (study [...]