Research

Energy balance

Low energy availability (EA < 45 kcal/kg FFM/day) in female endurance athletes causes a significant reduction in resting metabolic rate (RMR), serving as an energy-preserving mechanism.

If you are a female endurance athlete, maintaining a normal BMI does not guarantee you are eating enough to support your training. If you train heavily, you must ensure your energy availability is at least 45 kcal/kg of fat-free mass per day to prevent your metabolism from slowing down and to protect your menstrual and bone health. Monitor your energy intake relative to your training load, not just your scale weight.

GoodSupportsHIGH confidence
Subjects with low/reduced EA (< 45 kcal/kg FFM/day), had lower resting metabolic rate (RMR) compared with those with optimal EA [28.4 ± 2.0 kcal/kg fat-free mass (FFM)/day vs 30.5 ± 2.2 kcal/kg FFM/day, P < 0.01]
Anna Melin et al. · Scandinavian Journal of Medicine and Science in Sports · 2014

Why this rating

Observational study with clear statistical differences (P < 0.01) and large sample size for the specific population, but lacks an interventional manipulation of EA.

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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