Luteal-phase resistance training enhances nocturnal heat dissipation and delta power during sleep

Abstract

Study ObjectivesThis study examined the effects of resistance training on sleep architecture, physiological heat dissipation, and {delta} power in young adult women during the follicular and luteal phases of the menstrual cycle. MethodsNine healthy young women participated in a four-condition crossover protocol comprising (1) follicular phase non-exercise, (2) follicular phase exercise, (3) luteal phase non-exercise, and (4) luteal phase exercise. The exercise condition consisted of 30 minutes of resistance training at 70% of one-repetition maximum performed during the day. During each night, electroencephalography, body temperature, and core body temperature were measured in the home environment. The distal-proximal body temperature gradient (DPG), which is a validated indicator of heat dissipation, was calculated ResultsResistance training enhanced heat dissipation, as reflected by increased DPG values, and increased the proportion of stage N3 sleep during both menstrual cycle phases, with more pronounced effects during the luteal phase. Sleep from bedtime to wake time was divided into four equal segments. Under the luteal phase with exercise, the appearance of stage N3, {delta} power, and the DPG were elevated in the mid-to-late segments of sleep. ConclusionsThese findings suggest that daytime resistance training promotes nocturnal deep sleep and facilitates thermoregulatory heat loss, as indicated by an increased DPG, particularly during the luteal phase when thermoregulation is less stable than the follicular phase. This training may represent a practical intervention to improve sleep quality and physiological recovery in women across different phases of the menstrual cycle. STATEMENT OF SIGNIFICANCEWomen often experience sleep disturbances during the luteal phase of the menstrual cycle, but the physiological mechanisms and effective interventions remain unclear. This study shows that daytime resistance training enhances nighttime heat dissipation and increases slow-wave sleep during this phase. These findings suggest that exercise is a practical approach to alleviate menstrual cycle-related sleep issues. By clarifying how exercise interacts with thermoregulation and sleep across the cycle, this work contributes to understanding female-specific sleep physiology and supports the development of non-pharmacological strategies to improve womens sleep health in women. Future research should examine the long-term effects of daytime resistance training and compare different exercise modalities across diverse populations.