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

Abstract

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 using either Siri2 or Brožek et al. for ages 17–19 years when dehydrated only, and the Van Loan et al. BIA equation when euhydrated only were the most acceptable methods.
Conclusion: Regardless of hydration status, the skinfold equation by Slaughter et al. 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. BIA equation is recommended and if dehydrated the Durnin and Womersley using either Siri2 or Brožek et al. is recommended.

Keywords: bioelectric impedance analysis, body composition, deuterium dilution, jockey apprentice