| The effects of rapid rehydration (REHYD) (Oral and Intravenous) in dehydrated football athletes on cardiovascular, renal, fluid consumption, and thirst were evaluated. Seven healthy Division I football athletes underwent both REHYD protocols after exercise induced dehydration in a warm, humid environment to reduce body weight by 2.5%. Repeated measures ANOVA (trial x time) were used to evaluate for differences between trials. Paired t-tests were used for between trial analysis of temperature, humidity, weight loss, fluid consumed, and urine production. A p value of <.05 was considered significant.;Environmental conditions during dehydration were not different between trials. All subjects remained dehydrated at the conclusion of each day. Immediately after REHYD, blood and plasma volumes were significantly lower in the Oral than in the Intravenous trial. Significant shifts in fluid into and out of the vasculature occurred for the Intravenous trial. A significant 6.7% drop in blood volume from baseline at 0 min of REHYD in the Oral trial occurred. Urine osmolality was significantly higher at 180 min post REHYD in the Intravenous than the Oral trial. Renal tubular conservation of water was significantly higher in the Intravenous trial between 60 and 120 min. The Intravenous trial had significantly lower urine volumes at 180 min post REHYD than at 30 min post REHYD. Significantly greater ratings of thirst occurred in the Intravenous trial than the Oral trial at 0, 15, 30, and 120 min post REHYD. Serum osmolality was significantly higher for the Intravenous trial at 120 min and 180 min post REHYD. There were no significant differences between trials in total amount of fluid consumed ad libitum. Although in the Intravenous trial blood and plasma volumes were higher and subjects were thirstier conserving more water 3 hr after REHYD, total fluid consumed, total urine produced, and level of hydration did not differ from the Oral trial. Intravenous infusion caused significant shifts of fluid into and out of the vasculature. |
