Circulating Androgens in Women

Abstract

Physical exercise is known to strongly stimulate the endocrine system in both sexes. Among these hormones, androgens (e.g. testosterone, androstenedione, dehydroepiandrosterone) play key roles in the reproductive system, muscle growth and the prevention of bone loss. In female athletes, excessive physical exercise may lead to disorders, including delay in the onset of puberty, amenorrhoea and premature osteoporosis. The free and total fractions of circulating androgens vary in response to acute and chronic exercise/training (depending on the type), but the physiological role of these changes is not completely understood. Although it is commonly accepted that only the free fraction of steroids has a biological action, this hypothesis has recently been challenged. Indeed, a change in the total fraction of androgen concentration may have a significant impact on cells (inducing genomic or non-genomic signalling). The purpose of this review, therefore, is to visit the exercise-induced changes in androgen concentrations and emphasize their potential effects on female physiology. Despite some discrepancies in the published studies (generally due to differences in the types and intensities of the exercises studied, in the hormonal status of the group of women investigated and in the methods for androgen determination), exercise is globally able to induce an increase in circulating androgens. This can be observed after both resistance and endurance acute exercises. For chronic exercise/training, the picture is definitely less clear and there are even circumstances where exercise leads to a decrease of circulating androgens. We suggest that those changes have significant impact on female physiology and physical performance.

Dietary Intake, Body Composition, and Menstrual Cycle Changes during Competition Preparation and Recovery in a Drug-Free Figure Competitor: A Case Study

“…However, for competitors who plan to complete yearly, they may not have adequate time in between PREP cycles for menstrual cycle recovery. Prior investigations have noted that both resistance training and energy restriction are associated with alterations to reproductive hormones [14,42,43,44] leading to menstrual disruption (e.g., increases in estradiol and beta-endorphin which then reduce gonadotropin releasing hormone and luteinizing hormone pulsatility). Therefore, since physique athletes subject themselves to both intensive resistance training regimens and prolonged caloric restriction, they are at greater risk for menstrual disturbance and the associated insults to bone and metabolic health [21,22].…”

Marriage and motherhood are associated with lower testosterone concentrations in women

“…Based on previous work in other populations suggesting that energetic factors such as energy intake (Hainer et al, 2001), physical activity (Enea et al, 2011), and sleep (Andersen et al, 2011) may affect testosterone levels in women in some contexts, we included several additional variables in our secondary analyses. In the questionnaires, subjects reported typical hours of sleep per night as well as typical physical activity level in the past year (on a scale of 1–4; 1= sedentary or low activity, 2=moderate activities at least 4 hours per week, 3= hard activities to keep fit for at least 4 hours per week; 4=hard training or exercise for competition several times per week).…”

Work schedule and physically demanding work in relation to menstrual function: the Nurses’ Health Study 3

“…Working during nighttime hours may disturb the reproductive hormones that control the menstrual cycle, possibly through sleep disturbances or altered melatonin production. The mechanisms by which long working hours are related to adverse reproductive outcomes is unclear but, perhaps, are related to stress, mental or physical fatigue, or chronic sleep deprivation, disturbing circadian rhythms (27). Physically demanding work could influence menstrual function via altered circulating androgens (28), or it is possible psychosocial stress or fatigue resulting from repetitive physical demands may result in biochemical responses (eg, increased secretion of cortisol and α-amylase) which may reduce fertility (29).…”