Rationale and study design of an intervention of increased energy intake in women with exercise-associated menstrual disturbances to improve menstrual function and bone health: The REFUEL study

Purpose: Exercising women who consume inadequate energy relative to expenditure are at risk for downstream health consequences, such as menstrual cycle disturbances and poor bone health. Collectively, these conditions are known as the Female Athlete Triad (Triad). Clinicians often prescribe hormonal contraceptives to address this issue; however, the recommended treatment is reversal of the energy deficit. This paper describes the design of the REFUEL study, a randomized controlled trial (RCT) that explored the effectiveness of a 12-month intervention of increased energy intake on the reversal of an unhealthy energetic status and menstrual dysfunction and subsequent improvements in bone health in exercising women with severe menstrual cycle disturbances. Methods: Women between the ages of 18–35 years and participating in at least 2 h/week of purposeful exercise were recruited. Those who reported irregular or absent menstrual cycles and were determined to have an exercise-associated menstrual disturbance (EAMD) were randomized into either the treatment group (EAMD + Cal), which was instructed to increase caloric intake throughout the intervention, or a control group (EAMD Control). Women who reported eumenorrhea were eligible for the ovulatory (OV) Control group. Repeated measures of energetic and metabolic status, reproductive status, and skeletal health were obtained. Discussion: The REFUEL study is the first RCT to explore a non-pharmacological treatment approach among exercising women with the Triad. 118 women were randomized, and 55 women completed the entire study. The findings of this study have the potential to inform and alter clinical practice for exercising young women who present with this condition.