Using the Lean Tissue Index (LTI) as a Predictor Variable for Bone Mineral Density of Elite, Adolescent, Female Cross-Country Runners

Marc P Bonis, Mark Loftin, Melinda S Sothern

Abstract


Purpose: Determine the best body-composition variable for predicting bone mineral density (BMD) in the sub-population, which included body weight (WGT), lean tissue (LT), body mass index (BMI), body fat (BF), lean tissue index (LTI = LT/Height²), and body fat index (BFI = BF/Height²).

 

Methods: Measured BMD using DXA and estimated skeletal maturity (SM) using questionnaire data of subjects: 28 female runners (Mean Age + SD = 14.9 + 1.6 yrs).

 

Results: Partial correlations indicated LTI was the variable most highly associated (r = .712) with BMD. Multiple linear regression indicated LTI was the predictor variable with the best fit. Predictions of the dependent criterion variables, BMDleg and BMD, were calculated using the independent predictor variables, LTI and SM. Significant regression equations were found.  The subjects’ BMDleg  was found to be equal to (-2.486) + (2.912)SM + (5.540E-02)LTI,  [F(2,23) = 20.161, SEE = .0634] with an R² = .637;  and the subjects’ BMD was found to be equal to (-1.645) + (2.209)SM + (4.068E-02)LTI,  [F(2,23) = 18.828, SEE = .0487] with an R² = .621.

 

Conclusion: LTI was the body composition variable most highly associated with BMD (r = .712). LTI was also the best body-composition component to predict BMD (r = .788). Additional research regarding the LTI is recommended.


Keywords


Body Composition, Body Mass Index, Bone Growth, Amenorrhea

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DOI: https://doi.org/10.12922/jshp.v5i1.106

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