Comparative effectiveness of exercise interventions for primary dysmenorrhea: a systematic review and network meta-analysis.

Background: Exercise is increasingly being promoted as an effective treatment for primary dysmenorrhea (PD). This study aims to conduct a comprehensive network meta-analysis (NMA) of randomized controlled trials to identify the optimal types and dosages of exercise for managing PD in women.

Methods: Adhering to PRISMA-NMA guidelines, we systematically reviewed RCTs from the Cochrane Library, Web of Science, PubMed, and Embase databases up to May 23, 2024. Data analysis was performed using 'GEMTC' and 'BUGSnet' packages within a Bayesian framework in R and a hierarchy of exercise treatments was also calculated using surface under the cumulative ranking curve (SUCRA) values. Subgroup analyses were conducted to identify the most effective exercise regimens, including duration, frequency, and volume of the exercise interventions.

Results: Forty-nine studies representing 3,129 participants (1,640 exercises and 1,489 controls) were included. The results showed that all exercise interventions significantly reduced menstrual pain of the PD patients. Of six exercise intervention modalities based on the study ranked effectiveness, statistically significant reductions in pain intensity were found for resistance exercise and multi-component exercise. Multi-component exercise and stretching exercise were ranked best for menstrual symptoms, while core-strengthening exercise and multi-component exercise had the greatest impact on reducing pain duration. Significant and clinically important reductions or reliefs in pain occurred with 4 to 8 weeks of exercise training from all exercises, with resistance exercise showing the best efficacy when the duration exceeded 8 weeks, followed by multi-component exercise and mind-body exercise. Multi-component exercise and aerobic exercise with 1 to 3 sessions per week induced greater benefit in performance improvements, while resistance exercise with increased frequency showed the enhanced performance. Resistance exercise could elicit better efficacy within` 30-minute training duration, and multi-component exercise was ranked the best if such a training over 30 min.

Conclusion: This study provided quantitative insight into efficacy and effectiveness of exercise interventions on PD treatments. All six different exercises are associated with positive influence on PD management. Our study indicates that this exercise training induced adaptation may have therapeutic benefits for PD patients; however, such alterations and improvements are affected by exercise regiments.