The Prevalence of Hypohydration in School-Sponsored Athletes Across and Within Practice Sessions

Abstract

Hydration status monitoring through weight charts can help active individuals maintain optimal fluid balance and prevent health/performance impairments. This study aimed to determine the prevalence of athletes above an acute hypohydration threshold (within practices), a chronic hypohydration threshold (across practices), and the prevalence of athletes below the acute hypohydration threshold and above the chronic hypohydration threshold simultaneously (e.g., undetected chronic hypohydration). Second, involvement of baseline hydration verification (BV; with/without), sex, and competition level (high school, college/university) with acute hypohydration, chronic hypohydration, and undetected chronic hypohydration were also examined. Undetected chronic hypohydration was prevalent across sexes (6.4 ± 16.7% males; 1.4 ± 5.8% females) and competition levels (6.5 ± 16.4% high school; 5.4 ± 15.6% college/university). No significant differences existed across BV status for average acute hypohydration (with BV = 0.8; without BV = 0.8) or chronic hypohydation (with BV = 0.7; without BV = 0.8). All three calculations, absolute body mass loss, acute hypohydration, and chronic hypohydration, should be utilized to determine the prevalence of hypohydration, and they should also be used to assist athletic trainers while making clinical decisions regarding appropriate rehydration interventions.