title: Accuracy of dietary reference intake predictive equation for estimated energy requirements in female tennis athletes and non-athlete college students: comparison with the doubly labeled water method.
abstract: OBJECTIVE
  The purpose of this study was to assess the accuracy of a dietary reference intake (DRI) predictive equation for estimated energy requirements (EER) in female college tennis athletes and non-athlete students using doubly labeled water (DLW) as a reference method.
  
  
  METHODS
  Fifteen female college students, including eight tennis athletes and seven non-athlete subjects (aged between 19 to 24 years), were involved in the study. Subjects' total energy expenditure (TEE) was measured by the DLW method, and EER were calculated using the DRI predictive equation. The accuracy of this equation was assessed by comparing the EER calculated using the DRI predictive equation (EERDRI) and TEE measured by the DLW method (TEEDLW) based on calculation of percentage difference mean and percentage of accurate prediction. The agreement between the two methods was assessed by the Bland-Altman method.
  
  
  RESULTS
  The percentage difference mean between the methods was -1.1% in athletes and 1.8% in non-athlete subjects, whereas the percentage of accurate prediction was 37.5% and 85.7%, respectively. In the case of athletic subjects, the DRI predictive equation showed a clear bias negatively proportional to the subjects' TEE.
  
  
  CONCLUSIONS
  The results from this study suggest that the DRI predictive equation could be used to obtain EER in non-athlete female college students at a group level. However, this equation would be difficult to use in the case of athletes at the group and individual levels. The development of a new and more appropriate equation for the prediction of energy expenditure in athletes is proposed.
authors.affiliation: Department of Food and Nutrition, Gangneung-Wonju National University, 120 Gangneungdaehangno, Gangneung, Gangwon 25457, Korea.
authors.forename: Didace
authors.initials: D
authors.lastname: Ndahimana
authors.affiliation: Department of Food and Nutrition, Gangneung-Wonju National University, 120 Gangneungdaehangno, Gangneung, Gangwon 25457, Korea.
authors.forename: Sun-Hee
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Food and Nutrition, Gangneung-Wonju National University, 120 Gangneungdaehangno, Gangneung, Gangwon 25457, Korea.
authors.forename: Ye-Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Food and Nutrition, Gangneung-Wonju National University, 120 Gangneungdaehangno, Gangneung, Gangwon 25457, Korea.
authors.forename: Hee-Ryoung
authors.initials: HR
authors.lastname: Son
authors.affiliation: Department of Nutritional Education, National Institute of Health and Nutrition, Tokyo 162-8636, Japan.
authors.forename: Kazuko
authors.initials: K
authors.lastname: Ishikawa-Takata
authors.affiliation: Department of Physical Education, Korea University, Seoul 02841, Korea.
authors.forename: Jonghoon
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Food and Nutrition, Gangneung-Wonju National University, 120 Gangneungdaehangno, Gangneung, Gangwon 25457, Korea.
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Kim
keywords: Energy metabolism; athlete; physical activity