Nutrient intake and level of competitiveness among Japanese female university athletes

Nutritional intake that is sufficient and well balanced, or non-excessive, is ideal for improving athletic performance. Insufficient intake of nutrients may lead to a decrease in athletic ability, and, especially for female athletes, it is said that the occurrence of the triad of conditions consisting of eating function disorders, amenorrhea, and osteoporosis increases. Moreover, it is reported that nutrient intake affects levels of competitiveness, and clarifying nutrient intake by level of competitiveness among female athletes is very important toward providing them with effective nutritional guidance. This research therefore aimed to clarify the current status of nutrient intake among Japanese female university athletes and consider the relation between their levels of competitiveness and nutrient intake. The subjects were 123 female athletes belonging to a university athletic club (age: 19.9 ± 1.2 years, height: 162.5 ± 6.0 cm, weight: 58.6 ± 6.0 kg, BMI: 22.1 ± 1.8 kg/m²). The survey on nutrient intake employed the food frequency method (i.e., the food frequency questionnaire based on food groups, FFQg Ver. 3). As for groupings by level of competitiveness, athletes competing at the national and international tournament levels were classified as the upper group (n = 72), and those competing at levels including regional and city tournaments, as the lower group (n = 51). The results of the analysis revealed no significant differences in nutrient intake (energy, protein, fat, and carbohydrates), fat energy ratio, and carbohydrate energy ratio between the two groups. On the other hand, protein energy levels were significantly higher for the upper group than the lower group (p < 0.05). It thus became clear that highly competitive athletes tend to have high protein energy ratios. However, protein energy ratios were 13.7 ± 2.2% for the upper group and 12.8 ± 2.0% for the lower group—15 to 20% lower than the optimal standard value for energy and nutrient intake established for Japanese athletes. Furthermore, although a significant difference in fat energy ratios was not detected between the two groups, the upper group’s value was 34.6 ± 5.5% and the lower group’s was 34.5 ± 4.37%—greatly exceeding the standard value, by 25 to 30%. The above findings indicate that although a difference in protein energy ratios by level of competitiveness was identified in the nutrient intake of female university athletes, both groups need to lower their fat energy ratios and increase their protein energy ratios.