Research

Energy balance

Female athletes should maintain an energy availability of 40–45 kcal/kg fat-free mass per day to sustain eumenorrhea, bone health, and metabolic function, as habitual low energy availability leads to Relative Energy Deficiency in Sport (RED-S) or the Female Athlete Triad.

Calculate your daily energy needs by adding your basal metabolic rate to the energy cost of your exercise. Ensure the remaining calories (Energy Availability) are at least 40-45 kcal per kg of fat-free mass. If you are skipping meals or restricting calories to lose weight, you risk losing your period and bone density. Prioritize fueling your training to support your body's structural integrity.

GoodSupportsHIGH confidence
Obtaining optimal EA (40–45 kcal/kg FFM/day), eumenorrhea, and bone health are essential to sustaining metabolism and maximizing performance in women [76].
Kealey J. Wohlgemuth et al. · Journal of the International Society of Sports Nutrition · 2021

Why this rating

Based on a narrative review synthesizing multiple studies on energy availability and RED-S/Triad.

Source

Sex differences and considerations for female specific nutritional strategies: a narrative review

Kealey J. Wohlgemuth et al. · Journal of the International Society of Sports Nutrition · 2021

DOI 10.1186/s12970-021-00422-8

narrative_reviewCited 102×
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DOI resolved against Crossref · corpus check 2026-06-10

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