Menstrual cycle phase and running economy

Area of Science:

• Exercise Physiology
• Reproductive Endocrinology
• Sports Psychology

Background:

• The relationship between the menstrual cycle and exercise physiology in female athletes is complex.
• Hormonal fluctuations throughout the menstrual cycle can influence physiological responses to exercise.
• Understanding these changes is crucial for optimizing training and performance in female runners.

Purpose of the Study:

• To investigate the impact of different menstrual cycle phases on running economy (RE) in moderately-trained female runners.
• To examine the relationship between menstrual cycle phase, ventilatory responses, and mood states during rest and exercise.
• To determine if perceived exertion during running correlates with physiological and psychological changes across the menstrual cycle.

Main Methods:

• Eight eumenorrheic, moderately-trained female runners were studied across five menstrual cycle phases: early follicular (EF), late follicular (LF), early luteal (EL), mid-luteal (ML), and late luteal (LL).
• Physiological measurements included resting and exercise ventilation (L x min-1) and oxygen consumption (VO2max) at 55% and 80% VO2max.
• Mood states were assessed using the Profile of Mood States (POMS) questionnaire.

Main Results:

• Ventilation was significantly higher in the mid-luteal (ML) phase compared to the early follicular (EF) phase during rest, 55% VO2max, and 80% VO2max.
• Resting VO2 was significantly higher in ML compared to EF.
• Total mood disturbance, depression, fatigue, and confusion scores were significantly higher in ML versus EF, while vigor scores were lower.
• Running economy at 55% VO2max did not differ significantly between phases.
• Running economy at 80% VO2max was significantly less (higher VO2) during ML compared to EF.

Conclusions:

• Running economy at high intensity (80% VO2max) in moderately-trained female runners is influenced by menstrual cycle phase.
• Physiological changes, including increased ventilation and altered mood states (higher fatigue, lower vigor) during the mid-luteal phase, may contribute to these RE variations.
• These findings suggest that ventilatory drive and mood state fluctuations independently covary with RE changes throughout the menstrual cycle.