Effect of menstrual cycle phases on balance in athletic and non-athletic young females: a comparative study

Abstract Background Many studies have investigated how the menstrual cycle affects the musculoskeletal and neuromuscular systems. However, no studies have provided information about the difference between the effects of the menstrual cycle phases on balance between athletes and non-athletes. Purpose of the study. This study aimed to compare balance between athletes and non-athletes during ovulation and mid-luteal phases to determine if balance was influenced by hormonal fluctuations and which females might benefit from exercise safety guidelines based on the menstrual cycle phase. Methods Twenty-five female athletes and 25 non-athletes, aged from 18 to 25 years, participated in this study. Balance was assessed using the Biodex balance system, and serum estradiol level was evaluated using hormonal kits for all females during the ovulation and mid-luteal phases of the menstrual cycle. Results The paired t -test revealed that non-athletes showed a significant decrease in estradiol level ( p < 0.001), overall stability index ( p = 0.02), forward/backward ( p < 0.001) and mediolateral ( p = 0.007) stability indices, overall sway ( p = 0.007), forward/backward sway ( p < 0.001), and mediolateral sway ( p = 0.03) between the ovulation phase and mid-luteal phase; however, the athletes showed a significant decrease in estradiol level ( p < 0.001) and no significant difference ( p > 0.05) in the stability and sway indices between phases. Also, the unpaired t -test revealed a significant increase in the overall stability ( p = 0.021), forward/backward stability ( p < 0.001), mediolateral stability ( p = 0.002), overall and forward/backward sway ( p < 0.001) in the non-athletes compared to athletes during the ovulation phase only, and no significant difference ( p > 0.05) in the estradiol level and mediolateral sway index between athletes and non-athletes during both phases. Conclusion The menstrual cycle phase does not affect athletes’ balance control, but it impacts balance in non-athletes. Also, athletes have higher stability control than non-athletes during the ovulation phase, which indicates that non-athletes are more sensitive to hormonal fluctuations than athletes. Therefore, the non-athletes who plan to start an exercise program may require guidance on exercise safety based on the menstrual cycle phase.