Otsuka Pharmaceutical Co., Ltd.

Nutraceuticals
December 8, 2017

Observational study of 88 female Kindai University athletes
Relationship between premenstrual syndrome-induced interference in athletic performance and equol production status

The Kindai University Research Institute of Traditional Asian Medicine (Main Campus: Osaka, Japan; Director: Takashi Takeda) and the Saga Nutraceuticals Research Institute of Otsuka Pharmaceutical Co., Ltd. (Head Office: Tokyo, Japan; President: Tatsuo Higuchi) are engaged in joint research on equol, a biologically active substance metabolized in the human body from a soy isoflavone. Current research indicates a relation between interference in female athletes' performance due to premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD) and the ability to produce equol (equol production status).

Results of this research were released on December 8, 2017 at 17:00 (Japan time) in the Journal of Obstetrics and Gynaecology Research.

Main Points

  • Study to determine relation between PMS-induced interference in athletic performance and equol production status
  • Indicates the importance of equol production status and adequate intake of nutrients for overcoming PMS-induced performance interference
  • Supplementation of equol may be beneficial for improving female athletic performance

Summary

Equol is a biologically active substance metabolized in the human body from a soy isoflavone. Due to the presence of specific intestinal bacteria, some individuals are able to produce equol while others are non-producers. Previous research has indicated that approximately 42% of reproductive-aged Japanese women are equol producers*1; equol non-producers show more than twice the risk of PMS/PMDD*2.
To investigate the relation between PMS-induced interference in athletic performance and equol production status, this study analyzed data for 88 female athletes affiliated with Kindai University sports clubs. Compared to equol producers, equol non-producers showed a 3.3-times higher risk of PMS-induced performance interference. Restriction of bodyweight is also a risk factor for PMS-induced performance interference, indicating the importance of adequate intake of nutrients in addition to equol production status. New methods of alleviating PMS/PMDD through supplementation of equol may enable female athletes to perform at their best.

Publication

Title
Journal of Obstetrics and Gynaecology Research
The official Journal of the Asia and Oceania Federation of Obstetrics and Gynaecology and of the Japan Society of Obstetrics and Gynecology.
Article Title
Premenstrual symptoms interference and equol production status in Japanese collegiate athletes: A cross-sectional study
Authors
Takashi Takeda1, Tomomi Ueno2, Shigeto Uchiyama2 and Masami Shiina1
  1. 1Research Institute of Traditional Asian Medicine, Kindai University and
  2. 2Saga Nutraceuticals Research Institute of Otsuka Pharmaceutical Co., Ltd.

Background

Premenstrual syndrome (PMS) and severe premenstrual dysphoric disorder (PMDD) are comprised of a range of mood, behavioral and physical symptoms experienced before the menstrual period, which can significantly affect the quality of women's lives. In 2014, the Kindai University Research Institute of Traditional Asian Medicine reported that 44.3% of female athletes affiliated with university sports clubs indicated negative effects of premenstrual symptoms on performance in training or competition*3. It has also been clarified that equol producers show a lower risk of developing menopausal disorders, osteoporosis, cardiovascular disease and other estrogen-related diseases. Joint research conducted by the Kindai University Research Institute of Traditional Asian Medicine and Otsuka Pharmaceutical in 2016 showed that equol non-producers had a 2.4-times higher risk of PMS/PMDD*1.

Details of Study

A sample 189 female athletes affiliated with Kindai University sports clubs were recruited to participate in a soy challenge to determine equol production status and complete a questionnaire regarding PMS-related interference with athletic performance in training or competition. Complete data was collected and analyzed for 88 athletes; among the subjects, 73 (83%) were high-level athletes who had participated in national or international competition.
The prevalence of equol producers was 29.5%, similar to the low prevalence (20.6%) among young women in general. Awareness of interference in athletic performance due to PMS was cited by 48 subjects (54.5%). Equol non-producers showed a 3.3-times risk factor for PMS-induced performance decline. Restriction of bodyweight was also associated with an increased risk (4.9-times) of poor athletic performance, indicating the importance of balanced nutrition.

Project for Whole Implementation to Support and Ensure the Female Life

This research was undertaken as an intervention study on prevention of young women's sports injuries, supported by grants from the Japan Agency for Medical Research and Development (AMED) as part of the Project for Whole Implementation to Support and Ensure the Female Life.

Sources

  1. 1Takeda T. J Obstet Gynaecol Res. 42(11):1575-1580. 2016
  2. 2Takeda T. J Obstet Gynaecol Res. 42(11):1631. 2016
  3. 3Takeda T. J Pediatr Adolesc Gynecol. 28(4):215-8. 2015