Poster Topical Area: Sports Nutrition
Poster Board Number: 250
Adequate dietary intake is imperative to optimize body composition and maximize athletic performance. The specific dietary components contributing to optimal body composition and performance are still under investigation.
Objectives: To identify the dietary components predicting body composition and energy expenditure in female collegiate runners in comparison to inactive females.
Methods: Female runners (FR) logging ≥30 miles/week and inactive females (IF) with a body mass index (BMI) between 18.5 and 25 kg/m2 were included in this cross-sectional study. Percent lean mass (LM) and fat mass (FM) were measured by dual-energy X-ray absorptiometry, while resting metabolic rate (RMR) and total energy expenditure (TEE) were determined by air displacement plethysmograph. A Registered Dietitian Nutritionist obtained 24-hour dietary intake. Analysis of variance compared differences in mean outcomes between groups. Several stepwise linear regression models identified associations between outcomes (LM, FM, TEE, and RMR) and predictors (diet). Data are presented as mean ± SD.
Results: FR (n = 14; age 21.8±3.2; BMI 19.9±1.3) had a higher intake of carbohydrates (P = 0.004), percent kcal from carbohydrates (P = 0.018), and fiber (P = .001) than IF (N = 16; age 24.7±2.4; BMI 23.0±2.8). The FR had lower BMI (P < 0.001) and percent FM (P < .001), but higher percent LM (P < 0.001) and TEE (P < 0.001) than IF. RMR did not differ between groups. Lower protein (r = -0.620) and fiber (r = -0.038) intake were the only statistically significant predictors (P = 0.044) accounting for 50.5% of the variance for percent FM in FR. Dietary protein also predicted LM in FR (P = 0.029), where higher intake (r = 0.583) accounted for 28.5% of the variance. No statistically significant model was found between diet, RMR, and TEE in either group.
Conclusions: Dietary protein is a key nutrient optimizing body composition in FR. Low fiber intake contributes to higher FM in FR, which may be a surrogate for poorer diet quality. Interventional studies exploring the impact of protein and fiber on body composition among different types of athletes are needed.
Texas Woman's University