Effects of Moderate Altitude on Urinary Protein

Abstract

0760 PURPOSE: The purpose of the study was to determine the acute and chronic effects of ascent to moderate altitude (3416-m) on urinary protein while at rest an after completing a series of 1-min sprints. METHODS: Urinary protein was measured from the specimens of 6 healthy individuals at 4 times: (L1) lowland (243-m) before ascent, (A1) 1-day after ascent to altitude, (A2) 16-days after ascent to altitude, and (L2) 1-day after return to lowland. Urine specimens were collected at rest and after participants completed a series of 1-min sprints on a stationary bicycle ergometer to exhaustion. Urine protein concentration was divided by urine creatinine concentration (C) to correct for differing levels of hydration. RESULTS: ANOVA indicated significant main effects (P≤.05) of time (4 levels) and exercise (2 levels) but no interactions between time and exercise. Urine protein did not increase significantly from L1 (.09 ± .03-mg/mg C) to A1 (.20 ± .06-mg/mg C) but did significantly increase from L1 to A2 (.41 ± .13-mg/mg C) and L2 (.32 ± .09-mg/mg C). Urine protein was significantly higher after sprinting (.43 ± .11-mg/mg C) compared to rest (.08 ± .02-mg/mg C). CONCLUSION: Ascent to moderate altitude had an additive effect with sprint cycling exercise on the presence of protein in urine but that effect took 16-days to materialize and remained for at least 1-day after return to lowland. Urine protein levels seen after sprinting at A2 and L2 were consistent