Determining percentage body fat of male South African jockey apprentices irrespective of hydration status

Objective: The aim was to determine the most appropriate field techniques to measure %BF when both euhydrated and dehydrated. Design: A cross-sectional descriptive study was undertaken. Setting: South Africa. Subjects: 17 male apprentice jockeys (mean age 18.8 ± 1.7 years). Outcome measures: Agreement of %BF results determined using predictive equations based on skinfold thickness measurements and bioelectric impedance analysis (BIA) with that of the reference method, euhydrated deuterium dilution (eDD). Results: The mean %BF according to eDD was 9.5 ± 2.8%. The skinfold equations by Slaughter et al. (1988) for ages 8–18 years in either hydration state, Durnin and Womersley 1 using either Siri 2 or Brožek et al. 3 for ages 17–19 years when dehydrated only, and the Van Loan et al. 4 BIA equation when euhydrated only were the most acceptable methods. Conclusion: Regardless of hydration status, the skinfold equation by Slaughter et al. 5 is recommended for jockey apprentices 18 years and younger. For those > 19 years, the hydration state must be confirmed prior to measurement. If euhydrated, the Van Loan et al. 4 BIA equation is recommended and if dehydrated the Durnin and Womersley 1 using either Siri 2 or Brožek et al. 3 is recommended.