Of all the mixed messages of your cycle + training, one more clear thing is the impact it has on carb, fat, and protein metabolism. Which isn’t a bad thing — and is something we can tackle with appropriate nutritional strategies.
News flash: we need carbs to support performance. But this need, use & metabolism fluctuates if you experience a regular cycle (on-OC, you also need carbs too).
When it comes to carb loading (an acute increase of daily carb ~3-4 days out from competition), cis-women appear to have lower glycogen stores than men in their follicular phase & decreased storage. However — these differences do go away with higher carb intakes (8-12g/kg).
Within the cycle, there appears to be lower glycogen storage but greater “filling” capacity in the luteal phase. With lower storage and lower use (matched with greater fat use) in the mid-luteal phase. Differences again go away with adequate carb intakes BUT may be less necessary in the luteal phase due to decreased carb reliance/poorer glycogen storage capacity.
This is supported by more recent work suggesting slightly lower carb needs + higher fat in the second half of the cycle. However, carbs should be still be paired around performance (pre/intra/post) during this phase as this has been shown to decrease any negative performance impacts.
We likely need more carbs in the first half of the cycle (follicular phase) but more specific timing in the second half (luteal phase). Otherwise, overall carb guidelines for women & cycling individuals at this time appear to be in alignment with current carb intakes for active & athlete populations with these slight adjustments across the month.
- Exercise performance may be slightly impaired during the early follicular phase (McNulty et al., 2020) or not at all.
- Increased carbohydrate intake may be necessary during the follicular phase for women training, where glycogen availability may impact performance. This matches with recent work giving nutritional suggestions for cis-female athlete needs (Wohlgemuth et al., 2021)
- At this time, with adequate daily carb intake, sex differences do not appear to be detrimental to menstruating trainees (Impey et al. 2020, Moore et al., 2021).
- The currently accepted macronutrient range for carb intake is 45-65% of total calories. This ranges from 3-5g/kg in recreationally active to 6-10g/kg/day inactive populations looking to maximize performance.
- Carbohydrate loading & glycogen replenishing may differ between cis-men and cis-women, specifically due to hormonal differences across the cycle. Women should consider sticking to specific g/kg guidelines!
- Females can use carb load in either phase of the cycle consuming 8-10 g CHO/kg in the 3 days before a competition
- Current pre-exercise carb feeding is 1-4g/kg 1-4 hours prior. This may be more important in the follicular phase, where carb oxidation is higher.
- Women should consume at least 1g/kg CHO in the hours before exercise to maximize carb availability.
- After longer duration endurance exercise, females’ restoration of muscle glycogen is the TOP priority. The capacity to restore muscle glycogen is highest during the follicular phase. Females should focus on 0.75g/kg carbohydrate following prolonged endurance exercise.
- Carb intake should always be considered within the context of overall daily needs.
Simple straight takeaways:
• Women CAN carb load — they just need more. It may be less impactful in the luteal phase.
• Increase daily carb in the follicular phase
• Lower carbs with possibly higher fats (and calories) in the luteal phase.
• Timing of carbs to exercise in the luteal phase may be more important.
I have multiple other posts on metabolism & nutritional needs in my guides
Please save & share this if you found it helpful! 🤘🏻💕🙌🏻