Publications by authors named "Rebecca L Knight"
Reproductive endocrine function adapts to psychological, environmental, and energy-associated stressors. Multistressor environments upregulate hypothalamic-pituitary-adrenal (HPA) axis, causing suppression of the hypothalamic-pituitary-gonadal (HPG) axis, but it is not known if this pattern or its magnitude is sex biased. We compared HPG and HPA axis activity in 9 men and 34 women undergoing Army training.
View Article and Find Full Text PDFBackground: Women of reproductive age experience cyclical variation in the female sex steroid hormones 17β-estradiol and progesterone during the menstrual cycle that is attenuated by some hormonal contraceptives. Estrogens perform a primary function in sexual development and reproduction but have nonreproductive effects on bone, muscle, and sinew tissues (ie, ligaments and tendons), which may influence injury risk and physical performance.
Objective: The purpose of the study is to understand the effect of the menstrual cycle and hormonal contraceptive use on bone and calcium metabolism, and musculoskeletal health and performance.
Article Synopsis
- This study examined differences between men and women in energy balance, body composition, and hormonal markers during a 44-week military training program involving 23 trainees (14 women).
- Results showed that men had higher energy intake and expenditure, leading to greater energy deficits compared to women, who had lower energy intake and balance during the training.
- Hormonal changes were noted, with increased leptin in women, changes in testosterone levels for both sexes, and fluctuations in thyroid hormones, indicating the impact of military training on metabolic and endocrine functions.
This study investigated sex differences in, and the effect of protein supplementation on, bone metabolism during a 36-h military field exercise. Forty-four British Army Officer cadets (14 women) completed a 36-h field exercise. Participants consumed either their habitual diet [ = 14 women (Women) and = 15 men (Men Controls)] or the habitual diet with an additional 46.
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