Research

Energy balance

Within-day energy deficiency, where energy intake and expenditure are assessed in 1-hour intervals, reveals that athletes with menstrual dysfunction spend significantly more time in an energy-deficient state (>300 kcal deficit) than eumenorrheic athletes, even when total daily energy availability appears similar.

Don't just look at your total daily calories. If you train hard, ensure you are eating enough *around* your training sessions. Spreading your intake to avoid large deficits during and immediately after exercise may help protect your hormonal health, even if your total daily calories look okay on paper.

ModerateQualifiesMEDIUM confidence
Despite similar EA, female endurance athletes with menstrual dysfunction spent more time (22 vs. 18 h) in an energy deficient state exceeding 300 kcal compared to eumenorrheic athletes [55].
Danielle M. Logue et al. · Nutrients · 2020

Why this rating

Based on only two studies (one male, one female) examining within-day energy balance; viability is noted as unclear.

Source

Low Energy Availability in Athletes 2020: An Updated Narrative Review of Prevalence, Risk, Within-Day Energy Balance, Knowledge, and Impact on Sports Performance

Danielle M. Logue et al. · Nutrients · 2020

DOI 10.3390/nu12030835

narrative_reviewCited 286×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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