Research

Hormonal

Low energy availability (EA <30 kcal/kg FFM/day) causes functional hypothalamic amenorrhea (FHA) in female athletes through suppressed GnRH pulsatility, leading to decreased estradiol and progesterone.

If you are a female athlete experiencing missed periods, check your energy intake relative to your exercise expenditure. If your energy availability is consistently below 30 kcal per kg of fat-free mass per day, you are at high risk for hormonal suppression. Consult a specialist to address this before bone health is compromised.

GoodSupportsHIGH confidence
Aberrant gonadotropic releasing hormone (GnRH) pulsatility at the hypothalamus leads to abnormal pituitary secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), resulting in decreased estradiol and progesterone, inadequate folliculogenesis, and anovulation (Gordon et al., 2017).
Kirsty J. Elliott‐Sale et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2018

Why this rating

Based on multiple prospective and cross-sectional studies cited, though individual variability exists.

Source

Endocrine Effects of Relative Energy Deficiency in Sport

Kirsty J. Elliott‐Sale et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2018

DOI 10.1123/ijsnem.2018-0127

narrative_reviewCited 219×
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DOI resolved against Crossref · corpus check 2026-06-10

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