The hydration status of backpackers at high altitude

The purpose of the descriptive study was to determine the hydration status of recreational backpackers (n = 201) hiking at altitudes between 7,500 and 14,000 feet. Urine specific gravity was used to document the level of hydration of each subject entering or leaving the Bridger-Teton Wilderness. Demographic, risk, and knowledge factors were also obtained from the sample. Both pre-hike and post-hike subjects were dehydrated; pre-hike mean specific gravity was 1.018, and the post-hike mean was 1.023, showing a significant difference (t = -4.671, p < 0.0000). A small subset group (n = 10) entered both pre- and post-hike data and the findings were similar to the large group, showing a significant increase in specific gravity post-hike (t = -4.881, p < 0.0009). Interestingly, 24% (n = 130) of the post-hike males presented with hematuria.