CoachingAnswer

HOW DOES THE MENSTRUAL CYCLE AFFECT CYCLING TRAINING?

By Anthony WalshRoadman CyclingUpdated 10 July 2026

ANSWER

The menstrual cycle creates predictable hormonal shifts across roughly 28 days that influence energy availability, thermoregulation, recovery speed, and perceived effort. During the follicular phase (days 1-14), oestrogen rises and most women report higher energy and better high-intensity performance. During the luteal phase (days 15-28), progesterone rises, core temperature increases by 0.3-0.5 degrees Celsius, and perceived effort at the same wattage often feels harder. Awareness of these patterns lets you schedule harder sessions in the follicular phase and prioritise endurance or recovery work in the late luteal phase.

KEY TAKEAWAYS

The follicular phase (days 1-14) generally favours high-intensity work and strength gains.
The luteal phase (days 15-28) raises core temperature and perceived effort — adjust expectations.
Iron requirements increase during menstruation — monitor intake and consider supplementation.
Individual variation is large — track your own patterns before overhauling your programme.

WHO THIS IS FOR

IS THIS YOU?

The female cyclist whose performance fluctuates monthly

You notice predictable good and bad weeks but have never connected them to your cycle.

The coach working with female athletes

You want to understand how to periodise training around hormonal fluctuations without overcomplicating the programme.

THE ROADMAN VIEW

This is one of the most under-discussed topics in cycling coaching, and the research is finally catching up with what female athletes have known for decades: some weeks you feel invincible and some weeks the same watts feel brutal. That is not weakness — it is physiology.

The practical application is straightforward. Track your cycle alongside your training for three months. Look for patterns. If your hardest sessions consistently fall in the late luteal phase, move them. You are not training less — you are training smarter.

One critical caveat: individual variation is enormous. Some women notice no performance difference across their cycle. Others see dramatic swings. The only way to know your pattern is to track it.

EXPERT EVIDENCE

WHAT THE EXPERTS SAY

Dr Stacy SimsExercise physiologist, female athlete performance researcher
The hormonal environment of the early follicular phase — low oestrogen, low progesterone — most closely resembles the male hormonal profile and is when high-intensity training is typically best tolerated. The high-progesterone luteal phase increases core temperature, impairs plasma volume expansion, and can raise perceived effort at the same absolute intensity.

PRACTICAL APPLICATION

DO THIS WEEK

Track your cycle alongside training data for three months
Use a simple spreadsheet or an app like FitrWoman. Log cycle day, energy rating (1-5), sleep quality, and session RPE. After three months, look for repeating patterns in when you feel strong and when you feel flat.
Schedule key sessions in the follicular phase
If your tracking shows a clear pattern, schedule your hardest interval sessions and any FTP tests in days 5-12 of your cycle. This is when most women report the highest energy availability and the best high-intensity tolerance.
Adjust fuelling in the luteal phase
Progesterone increases carbohydrate oxidation and can reduce fat utilisation. Increase carbohydrate intake by 10-15% during the luteal phase, particularly around training sessions, to compensate.

COMMON MISTAKES

WHAT CYCLISTS GET WRONG

MISTAKEAssuming every woman responds the same way to cycle phases.
FIXIndividual variation is massive. Track your own data before making any changes. Some women perform best in the luteal phase — the research describes averages, not universals.
MISTAKESkipping training entirely during menstruation.
FIXLight-to-moderate exercise during menstruation often reduces cramps and improves mood. Adjust intensity if needed, but complete rest is rarely necessary unless symptoms are severe.
MISTAKEIgnoring iron status.
FIXMenstrual blood loss depletes iron stores. If you feel persistently fatigued, get a ferritin blood test. Supplementation under medical guidance can be transformative for training quality.

FAQ

FREQUENTLY ASKED QUESTIONS

Should I avoid high-intensity training during my period?

Not necessarily. Menstruation occurs at the start of the follicular phase, when hormone levels are low. Many women actually perform well during their period once the first day or two has passed. Adjust based on how you feel, not on assumptions.

Does hormonal contraception change the picture?

Yes. Hormonal contraception overrides the natural cycle and creates a different hormonal environment. The follicular/luteal framework does not apply in the same way. Track your own patterns on your specific contraception.

Can the menstrual cycle affect recovery?

Progesterone in the luteal phase can impair sleep quality and increase inflammation, both of which slow recovery. Prioritise sleep hygiene and consider slightly longer recovery between hard sessions in the second half of your cycle.

Should I eat differently across my cycle?

Slightly. The luteal phase increases carbohydrate demand. Aim for 10-15% more carbohydrate around training sessions in the luteal phase. Protein requirements remain consistent throughout the cycle.

Does the menstrual cycle affect hydration needs?

Yes. The luteal phase raises core temperature and can impair plasma volume. Increase fluid intake, particularly during hot-weather riding in the second half of your cycle. Adding sodium to drinks helps with fluid retention.

Is it normal for FTP to vary across the menstrual cycle?

Measurable FTP variations of 3-5% across the cycle have been observed in research, though individual responses vary widely. If your FTP test consistently falls in the luteal phase, consider retesting in the follicular phase for a truer baseline.