Research

Hormonal

Low energy availability (EA < 30 kcal/kg FFM/day) in female athletes is associated with reduced blood glucose levels and altered hormone profiles, including lower T3 and elevated cortisol.

Severe energy deficiency can disrupt your hormones and blood sugar. If you are not eating enough to support your training, your body may lower thyroid hormone levels and increase stress hormones like cortisol, which can further impact your health and performance.

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In healthy young female adults, 5 days of EA < 30 kcal/kg FFM/day has been shown to reduce blood glucose (and thereby carbohydrate availability) and hypothalamic-pituitary-axis hormones, like triiodothyronine (T3)... and to elevate cortisol
Anna Melin et al. · Scandinavian Journal of Medicine and Science in Sports · 2014

Why this rating

This node relies on a citation of a previous study (Loucks & Thuma, 2003) rather than primary data from this specific paper, though the current paper's findings support the general conclusion.

Source

Energy availability and the female athlete triad in elite endurance athletes

Anna Melin et al. · Scandinavian Journal of Medicine and Science in Sports · 2014

DOI 10.1111/sms.12261

cross_sectional · n=40Cited 282×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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