Nutritional strategies associated with low energy availability in Division I female soccer players

Open Access
Author:
Kindler, Joseph Michael
Area of Honors:
Kinesiology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Nancy Williams, Thesis Supervisor
  • Stephen Jacob Piazza, Honors Advisor
Keywords:
  • Female Athlete Triad
  • energy availability
  • female soccer
  • nutrition
Abstract:
Low dietary energy intake in relation to high exercise energy expenditure resulting in low energy availability (EA) has been observed in elite female soccer players. Short term studies manipulating dietary energy intake and exercise energy expenditure have shown that negative metabolic, reproductive, and bone related changes occur below an EA of 30 kcal/kg LBM. To date, no studies have examined the association between nutritional practices such as dietary carbohydrate and protein intake, energy density, and caloric distribution of dietary energy intake and levels of EA. The purpose of this study was to examine changes in energy and macronutrient consumption across the season and to evaluate dietary practices such as macronutrient and energy intake, energy density, and dietary energy distribution that may be associated with low energy availability in Division I female soccer players across a competitive season. Nineteen participants (18-21 years; VO2max: 57.0±1.0 ml/kg/min) were studied during the pre, mid, and post season. When grouped according to whether they had an EA above or below 30 kcal/kg LBM, the proportion of Division I female soccer players who did not meet the American College of Sports Medicine (ACSM) recommendations for dietary carbohydrate and protein intake was determined. The proportion of Division I female soccer players who did not meet ACSM carbohydrate recommendations significantly differed from the proportion of players who did meet the recommendations during the pre season, but not the mid season (χ2 = 11.8, p = 0.01). The proportion of Division I female soccer players who did not meet ACSM protein recommendations significantly differed from the proportion of players who did meet the recommendations during the mid season, but not the pre season. A lower energy density at lunch (1.2 ± 0.2 vs. 1.8 ± 0.1 kcal/g; p = 0.034) and dinner (0.8 ± 0.1 vs. 1.4 ± 0.1 kcal/g; p = 0.004) was observed in Division I female soccer players with low compared to higher energy availability during the pre and mid season, respectively. Compared to sport drinks, other drinks, and bars/gels/beans, food comprised the greatest proportion of total kilocalories consumed by Division I female soccer players with higher (79%) and low EA (84%) when pre and mid season phases were combined. Sport drinks, the next highest proportion of total kilocalories consumed, comprised 8.8% and 5.9% of total calories in higher EA and low EA players, respectively. Nutritional practices such as inadequate dietary carbohydrate and protein intake and low energy dense diets at particular meals i.e., lunch and dinner were associated with low EA in this sample of Division I female soccer players. Identifying such practices may be important in preventing low EA in elite female athletes.