Energy Availability in Female Elite Soccer Players and Sedentary Controls

Objective The aim of this study was to assess energy availability in female soccer players, as being one of the main nutritional concern in this group which is linked with endocrine disturbances and low bone mineral density.

Methods Elite female soccer players (n=17) and controls (n=9) registered food intake and physical activity for 7 days. Daily energy expenditure (EE) and energy expenditure during exercise (BEE) was estimated by accelerometry. Energy availability was calculated; Energy intake (EI)- EEE. Low energy availability (LEA) is defined as < 30 kcal?kg fat free mass (FFM)?day. Energy balance (EB) was calculated as EI-EE. Data is presented as mean ± SD.

Results EI was higher for soccer players 2602 ± 425 kcal compared with controls, 2117 ± 541 kcal (p=0.02) as was EE; 2984 ± 618 compared to 2249 ± 699 kcal, respectively (p=0.02). Mean energy balance was -381 ± 564 kcal for soccer players and -130 ± 845 kcal for controls (NS). Mean energy availability was 31.4 ± 13.4 and 39.4 ± 14.6 kcal?kg FFM?day for soccer players and controls respectively (NS). The prevalence of LEA was 53% (n=9) among soccer players and 44% (n=4) among controls.

Discussion The large variations in EI and EE and the negative mean EB in both soccer players and controls question the usefulness of the definition of LEA as this only includes EEE. The current data support that variation in EE during non exercise activities should be considered when analysing energy availability.