Nutrition for Training, and for Women's Health

Fuelling around training

For most recreational lifters training under an hour at moderate intensity, total daily intake matters far more than precise pre- or post-workout food choices (see Section 9). For longer or higher-intensity sessions, a carbohydrate-containing meal 2–3 hours beforehand improves performance and reduces perceived effort compared with training fully fasted, though fasted training itself is not harmful for most healthy people doing moderate-intensity work^[16][51].

Nutrition across the menstrual cycle

Resting metabolic rate rises modestly during the luteal phase (the second half of the cycle, after ovulation) compared with the follicular phase — early controlled research measured an increase in the region of roughly 100 kcal/day, though the exact size varies between studies and individuals^[65]. This is consistent with, and partly explains, commonly reported increases in appetite and cravings during this window. This is a real physiological shift, not simply a lack of willpower, and modestly adjusting intake upward during the luteal phase rather than fighting it rigidly tends to support better long-term adherence. Iron needs are also meaningfully higher in menstruating women due to monthly blood loss, making iron-rich food sources or monitoring worth specific attention (see Section 6).

Pregnancy and breastfeeding

Energy needs increase modestly in pregnancy (roughly an additional 300 kcal/day in the second and third trimesters) and more substantially during breastfeeding (roughly an additional 400–500 kcal/day), but the bigger shift is in specific nutrient needs: folate and iodine requirements rise notably, and folate supplementation is specifically recommended before conception and through the first trimester to reduce neural tube defect risk. This guide does not replace specific clinical guidance during pregnancy, which should come from a midwife or doctor.

Relative Energy Deficiency in Sport (RED-S)

Chronic under-eating relative to training demands — common in sports emphasising leanness, and in aggressive, prolonged dieting more generally — can disrupt reproductive hormone function, bone density, and metabolic rate, a syndrome now described as RED-S. In women this frequently presents first as a missed or irregular menstrual cycle, which is a physiological warning sign and should not be dismissed as a convenient side effect of being lean^[66]. Persistent missed periods alongside heavy training and restrictive eating warrant a conversation with a doctor, not just an adjustment to macros.