Background: Female physical performance can be influenced by perceived, physiological, and physical factors, making it an important field for further research. Aims: The purpose of this study was to analyze the effects of the menstrual cycle (MC) on the cardiovascular and neuromuscular load of amateur women athletes in CrossFit® during real training situations. Methods: Resistance-trained CrossFit® athletes (without oral contraception) and eumenorrheic women participated in this study (age: 29.6 ± 4.06 years; height: 1.59.3 ± 0.06 m; body mass: 61.22 ± 4.59 kg). A cross-sectional, descriptive study was conducted to evaluate heart rate variability (rMSSD), upper-body strength, muscular endurance, and power performance. The data were analyzed using a one-way repeated-measures ANOVA and the nonparametric Friedman test to assess significant differences among the follicular, ovulatory, and luteal phases for all assessments. The significance was set at p ≤ 0.05. Result: Results revealed no significant differences between the menstrual cycle phases in performance: (HRV RMSSD: H: 0.830, p: 0.443, η2: 0.038), (Push up test: H: 0.041, p: 0.959, η2: 0.002), (countermovement jump: H: 11.921, p: 0.050, η2: 0.362), (rate force development CMJ: H: 1.242, p: 0.299, η2: 0.056), (squat jump: H: 0.439, p: 0.648, η2: 0.020), (rate force development SJ: H: 1.703, p: 0.194, η2: 0.075), (isometric mid-thigh pull: H: 0.019, p: 0.981, η2: 9.132x10-4). Performance is not altered during the MC in female CrossFit® trained athletes. Conclusion: These findings demonstrate that the menstrual cycle does not significantly influence internal and external training load, heart rate variability, or strength and power performance in this population.
Yanez et al. (2026) studied this question.