Dietary Behaviors Associated With Lower Nutrient Intake In Collegiate Endurance Runners

Collegiate endurance runners are at elevated risk for bone stress injury (BSI) and other outcomes linked to nutrient deficits; however, limited studies have explored dietary behaviors associated with undereating in this population. PURPOSE: Evaluate the intake level of nutrients among collegiate endurance runners reporting dietary restriction and other dietary behaviors associated with lower nutrient intake. METHODS: During the 2015 to 2017 cross-country seasons, seventy-eight endurance runners (n = 39 males and 39 females; age: 19.5y ± 1.3; body mass index (BMI): 20.5 ± 1.6 kg/m2; average weekly running mileage: 57.9 ± 16.2) completed a standardized nutrition assessment with a team sports dietitian including an interviewer-administrated dietary recall. Runners also reported eating behaviors, dietary restrictions and nutrition goals. Each runner’s height and weight were measured to calculate BMI. Independent samples t-tests assessed group differences in snacks per day and nutrient intake according to dietary behaviors. Analyses was limited to runners without current injury. RESULTS: Seventeen (21.8%) runners reported restricting one or more foods including gluten (n = 5), dairy (n = 4), meat (n = 3), nuts (n = 2), fats/sweets (n = 2), and seafood (n = 1). Runners reporting a dietary restriction had lower intake of vitamin D (264.7 ± 218.3 IU vs. 424.9 ± 367.4 IU, p = 0.046), vitamin C (105.6 ± 77.0 mg vs. 167.7 ± 131.7 mg, p = 0.034), and niacin (61.0 ± 19.1 vs. 77.1 ± 52.0 niacin equivalent, p = 0.026). Females with dietary restriction reported eating fewer snacks/day (1.9 ± 1.0 vs. 2.8 ± 0.9, p = 0.007) and lower calcium intake (1093.4 ± 467.5 mg vs. 1371.0 ± 426.7 mg, p = 0.046). Eating 0-1 snacks per day (n = 13), vs. >1 snack/day, was associated with lower intake of energy (44.2 ± 14.2 kcal/kg vs. 50.9 ± 16.1 kcal/kg, p = 0.08) and carbohydrates (4.6 ± 1.4 g/kg vs. 6.2 ± 2.2 g/kg, p = 0.009). CONCLUSIONS: Dietary restriction and eating <2 snacks/day was associated with lower nutrient intake. Future research is needed to further explore dietary behaviors contributing to nutrient deficits in in this population. This study was funded by the Pacific Athletic Conference (Pac-12), the American Medical Society for Sports Medicine (AMSSM), and the Stanford Medical Scholars Research Grant.