Objectives: This study aimed to characterize the sleep quality and nutrient intake of Japanese female college athletes to provide specific conditioning support. Methods: A cross-sectional survey conducted between December 2019 and January 2020 during the regular training season in Niigata City, located at 139°02′ E longitude and 37°55′ N latitude. Overall, 120 female university student-athletes from eight clubs were selected. All sports were at the national level of competition. The Pittsburgh Sleep Quality Index (PSQI) assessed sleep quality. Nutrient intake was assessed using Excel nutrition software through the Food Intake Frequency Questionnaire. Results: The mean PSQI score was 4.5 ± 2.5, with 29% of participants having a PSQI score ≥ 5.5. The sleep duration was 6.8 ± 1.1 h, with 45% of participants sleeping <7 h. The energy intake was 1800 ± 419 kcal, with no correlation between PSQI score and nutrient intake. Conclusions: PSQI scores were higher compared with other studies, but many participants had shorter sleep duration and lower nutrient intake, these data suggest that there is the possibility of improving the habits of Japanese athletes by increasing the subjects’ amount of sleep time and food intake.

This study examined the self-assessment of Niigata’s and Khabarovsk’s adolescents’ health status and their willingness to be vaccinated during the COVID-19 pandemic. A self-reported questionnaire was administered to 735 boys and girls (aged 15 years) from Niigata, Japan (n = 387), and Khabarovsk, Russia (n = 394), between May and July 2021. Specifically, this questionnaire focused on COVID-19, including a self-assessment of health status, adaptation to a new lifestyle, and impressions about the COVID-19 vaccination. The self-assessment was based on a 4-point scale: “Got very bad”; “Got a little bit bad”; “Did not change”; “Got better/I don’t know”. Additionally, binomial logistic regression was conducted to determine the association between the self-assessment of health status and the factors exacerbating their responses. Based on the findings, 25.7 and 29.9% of Niigata and Khabarovsk’s adolescents, respectively, selected “Got very bad” and “Got a little bit bad” for their self-assessments, while the binomial logistic regression showed that the difficulty of adapting to a new lifestyle was a factor worsening the boys’ subjective health. However, the items could not explain the deterioration of their subjective health in girls. Moreover, 76.9% of Niigata’s adolescents were positive about the COVID-19 vaccination, compared to 35.5% of the adolescents in Khabarovsk.

This study aimed to determine whether adolescents’ leisure screen time differed during the coronavirus disease 2019 (COVID-19) pandemic compared to before the pandemic, and to identify factors that affect leisure screen time among Japanese high school students. The Health Behavior in School Children questionnaire was used to investigate differences in eating habits and physical and mental health. The results showed that the leisure screen time of Japanese high school students was 2.6 h (SD = 1.4) before the pandemic, and 3.2 h (SD = 1.5) during the pandemic. The factors that increased leisure screen time were found to differ between boys and girls. No significant deterioration in physical and mental health was observed. The impact of the pandemic on eating habits differed in boys and girls. Boys reported “not feeling great about life” as a factor that increased leisure screen time during the pandemic, suggesting that negative emotions influenced the increase in leisure screen time. The pandemic had a significant impact on girls’ leisure screen time. Longer screen time should be carefully monitored because it can lead to sleep disturbances, worsening of mental health, and obesity. Compared with before the pandemic, the health status of boys and girls changed little. Eating habits tended to improve for both boys and girls.

Ensuring proper energy, nutrient intake, and sleep is vital for athlete health and competitiveness. Despite previous studies investigating the nutrient intake among top-level collegiate female athletes in Japan, the status of snack consumption remains unclear. This study addressed this gap by surveying 70 top-level female university athletes. The survey included a self-administered diet history questionnaire, a qualitative food intake frequency survey, and a survey on snack and dietary supplement use. The results revealed a low frequency of snack intake (2.1 ± 2.3 days/week), with 55.7% of athletes reporting snack consumption. The energy intake in the snack-intake group was significantly higher than that in the without-snack-intake group (31.5 ± 10.0 vs. 26.6 ± 9.92 kcal/kg of BM, p = 0.047). Similarly, carbohydrate intake was significantly higher in the snack-intake group than in the without-snack-intake group (4.84 ± 1.71 vs. 3.96 ± 1.65 g/kg of BM/day, p = 0.035). However, neither group reached the recommended value of 5–8 g/kg of BM/day during the medium training period. Overall, this study emphasizes inadequate energy intake even among athletes with a high snack intake frequency, highlighting the necessity to enhance overall food consumption and underscoring the importance of nutritional education for incorporating appropriate complementary meals to improve performance.

In recent years, there has been an increase in the number of hypertensive diseases and the various diseases associated with them. A major cause of these is excessive salt intake. The purpose of the present study was to examine whether chewing hard foods lowers the saltiness threshold. Fifteen subjects (fourteen women and one man) participated in the present study. Two types of gummies are available as ingredients: hard and soft gummies. The saltiness thresholds before and after chewing of each gummi were studied using 11 different NaCl solutions. Then, points of subjective equality (PSEs) were calculated to detect changes in the saltiness for each subject. In the soft Gumi condition, there was no significant difference in PSE for the saltiness between before and after ingesting Gumi (p>0.05), while in the hard Gumi condition, the PSE for the saltiness significantly decreased after ingesting Gumi compared with the value of before ingesting Gumi (p=0.001). From these results, we concluded that sensitivity to saltiness would increase after mastication of hard foods such as hard Gumi.

This study investigated the percentage of iron deficiency anemia (IDA) and iron deficiency (ID) among 71 elite female athletes at a Japanese university and assessed their dietary habits. IDA was identified in 9.9% (n = 7) of participants, and only 22.5% (n = 16) self-reported dietary practices aimed at preventing or managing ID/IDA. Notably, 52.1% (n = 37) of the athletes exhibited IDA or ID but lacked an appropriate dietary approach. Moreover, even among those who reported an intentional dietary approach to the prevention or management of ID/IDA, the intake of iron- and vitamin C-rich foods was insufficient, limiting the effectiveness of their efforts. These findings highlight a gap between awareness and effective practice, indicating that many female athletes in Japan, despite being at elevated risk, do not follow evidence-based dietary strategies for preventing or treating ID/IDA. Targeted nutritional education and routine screening of iron status are strongly recommended for this population.