OBJECTIVE: To examine the relationships between changes in static prestage and poststage measures of commonly used hematological and urinary markers of hydration status and body mass (BM) in participants in a 3-day trail run. DESIGN: Descriptive field study. SETTING: Three Cranes Challenge trail run, South Africa. PARTICIPANTS: Twenty (6 men and 14 women) amateur runners. [...]
Biomarkers of hydration change in response to acute dehydration; however, their responsiveness to changes in fluid intake volume, without exercise or heat exposure, has not been adequately described. Moreover, patterns of circadian variation in hydration biomarkers have not been established. The study aims were to (1) assess the response of hydration biomarkers to changes in [...]
Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance. Unfortunately, dehydration can be difficult to assess, and there is no single, universal gold standard for decision making. In this article, we review the physiologic basis for understanding quantitative dehydration assessment. We highlight how phenomenologic interpretations of [...]