Ultra Marathon Training During Menstruation: The Complete Science-Backed Guide

Why Menstrual Cycle Matters for Female Ultrarunners

Running an ultramarathon is hard. Running one while your body is busy with its own monthly rhythm? That’s next-level endurance.

In the last decade, the world of ultra running has changed. More women than ever are lining up for 50K, 100K, even 24-hour races. And with that rise comes a question only women truly understand: “How do I train and race with my period?”

Let’s be honest—talking about periods in sports was taboo for too long. But the truth is, our menstrual cycle is as real as our training plan or the hills we climb. Some days, we feel powerful. Others, we feel drained, crampy, or just… off.

Here’s the good news: Science now backs what many women always suspected: with a little awareness, you can run strong all month long. Understanding your cycle helps you plan harder workouts, spot recovery days, fuel better, and avoid injury. You don’t have to “tough it out” or ignore what your body tells you. Instead, you can learn, adapt, and even thrive.

This guide is for every female runner who’s ever wondered why some days feel different—and for every coach or training partner who wants to help. You’ll find science, real-world tips, and zero shame. Let’s make the cycle your secret training tool, not a setback.

What’s ahead? • A runner’s explanation of the menstrual cycle • How each phase impacts training and racing • Nutrition, injury, mood, and tracking advice • Practical tips for every level of athlete

Menstrual Cycle 101: Phases & Hormones

The menstrual cycle isn’t just about “that time of the month.” It’s a carefully choreographed dance of hormones that affects your energy, mood, motivation, and sometimes even your pace. Every cycle has four main phases, each with its own rhythm.

• Menstruation (Days 1–5): The start of your period. Bleeding begins, hormones (estrogen and progesterone) are at their lowest. Some runners feel wiped out, others barely notice. Cramps, fatigue, and heavy legs are common, but so is a sense of “fresh start.”
• Follicular Phase (Days 6–13): Estrogen begins to climb. Many women notice their mood and energy lift, soreness fades, and running feels smoother. This is often a sweet spot for speedwork or longer runs.
• Ovulation (Day 14): A single day when estrogen peaks, and your body releases an egg. You might feel powerful, confident, and light on your feet. For some, ovulation comes with twinges, headaches, or even an increased risk of ligament injury.
• Luteal Phase (Days 15–28): Progesterone rises. Your body temperature goes up, sleep can get patchy, and you may retain water. Many runners notice heavier legs, mood dips, or increased hunger. PMS can hit hard here: bloating, cravings, irritability, and sometimes self-doubt.

Every runner is different. Some feel the impact of each phase, others only a little. The trick? Start tracking your cycle and see what’s true for you.

Pro tip: Keep a log of your cycle alongside your training. You’ll soon spot patterns and know when to push—or when to recover.

How the Menstrual Cycle Affects Ultra-Endurance Performance

Here’s the number one question: “Will my period slow me down?” The honest answer is: It depends—but probably less than you think.

Research shows that most women’s actual running performance doesn’t drop dramatically at any cycle phase. Elite and everyday runners have broken PRs during their period, in the follicular phase, or right before their period.

• More than half of top female athletes feel their period affects performance—mainly due to cramps, fatigue, or “off” days.
• Mid-cycle (follicular or ovulation) is often when women report their best energy and confidence.
• Some studies even show no measurable change in running speed or endurance from phase to phase. Subjective feelings (tired, heavy, sluggish) matter more than actual physiology.
• For some, “bad days” are mental as much as physical. Mood, motivation, and self-doubt can make any run feel harder—especially premenstrual days.

“Some months, I surprise myself with a strong long run on day 2 of my period. Other months, I take it easy, eat chocolate, and rest. Both are valid.”

Bottom line: Track your cycle, notice patterns, and listen to your body. If a workout feels off, it’s okay. If you feel great, enjoy the ride!

Training Adaptation and Progression Throughout the Cycle

Can you plan your training around your cycle and get faster? Maybe. For some women, matching hard workouts to “high-energy” phases pays off. For others, a steady, flexible routine works best.

What science says: Training gains—like better VO₂max, stronger legs, improved recovery—happen in every phase. Some research hints that intervals or speedwork feel easier in the follicular phase, when estrogen is up. Other studies find no difference, especially in experienced runners who listen to their bodies.

• Follicular/ovulation: You might handle harder sessions or longer runs with less fatigue. Schedule key workouts here if it feels right.
• Luteal/premenstrual: Energy drops, recovery slows, sleep is disrupted. Take extra rest, shorten hard workouts, or switch to cross-training.
• Over a few months, note your good and tough days. Most runners find their own rhythm.

Lost Pace: Training isn’t about fighting your body. It’s about working with it. Use your cycle as a “training compass,” not a set of handcuffs.

Injury Risk and Recovery: What the Research Shows

Ever rolled an ankle for no reason, or tweaked a knee during an otherwise normal week? Hormones may be involved.

• Ovulation: Estrogen peaks. Joints and ligaments can get looser. Some studies show higher rates of ACL and ankle injuries in this window—especially for aggressive trail runners or racers.
• Late luteal: Progesterone and PMS rise. Fatigue, slower reaction time, and muscle soreness increase. Many runners report more minor strains, “niggles,” or extra DOMS after hard runs.
• Menstruation: Some women notice extra aches, especially if iron is low or sleep suffers. But, many complete tough runs just fine.

How to lower risk: • Warm up longer on high-risk days. • Add balance and core drills. • Don’t push through sharp pain—substitute, rest, or seek help early. • Post-run, focus on gentle stretching, hydration, and sleep.

Recovery matters: If soreness lingers longer than normal, respect it. Your cycle can slow down recovery—don’t rush the process.

Nutrition and Hydration Strategies for Each Cycle Phase

What you eat and drink matters. But during your cycle, it matters even more. Your body’s needs shift—sometimes subtly, sometimes a lot.

• After your period: Top up iron stores with lentils, spinach, beans, seeds, or a supplement. Vitamin C helps you absorb it.
• Follicular/ovulation: Carbohydrates fuel hard efforts best. This is a great time for faster workouts and higher mileage—don’t skimp on carbs!
• Luteal phase: Hunger often increases. Listen to cravings for protein, healthy fats, and anti-inflammatory foods like walnuts, berries, and turmeric. Hydrate more—your body temperature and sweat rate rise.
• PMS week: Bloating, salt cravings, or mood dips are common. Stay hydrated, avoid super-salty processed snacks, and add magnesium-rich foods if cramps bother you.

Sample meal tweaks: • Add an extra snack on heavy training days or when hungry. • Experiment with herbal teas or a pinch of sea salt in your water to manage bloating. • Don’t fear chocolate—it can be part of recovery, too!

Lost Pace: There’s no “one size fits all” meal plan. Track how food, drink, and cravings shift with your cycle and adjust as you go.

Psychological Factors, Motivation, and Mood

Sometimes the hardest part of training isn’t physical. It’s what’s happening in your head. The menstrual cycle can play tricks with your motivation, confidence, and emotions.

• PMS and the luteal phase: Many women feel their mood dip, anxiety or irritability rise, and self-doubt creep in—often a week before their period starts.
• Follicular phase: Mood and motivation usually lift. Runs feel lighter, and the world just seems a bit brighter.
• Menstruation: Fatigue can blend with frustration, especially if you’re missing a key session or a race falls on your period. But many runners also report a mental “reset” and fresh start.

What helps? • Don’t judge yourself for low days—accept them as part of the cycle. • Practice mindfulness, gentle yoga, or short outdoor walks. • Journal your mood and motivation alongside your training log. • Set process goals (“I’ll show up and do what I can”) instead of fixating on paces.

Lost Pace: Some days are for pushing your limits. Other days are for showing up, going easy, and giving yourself grace. You’re an ultrarunner—all of it counts.

Menstrual Cycle Tracking: Apps, Wearables, and Best Practices

If you want to turn your menstrual cycle into a training tool, start tracking it—just like you track your mileage or pace. You don’t need fancy tech (though it helps), just a habit of recording a few key things.

• Basic method: Mark the first day of your period each month. Note your mood, energy, and any standout symptoms in your running log or a calendar.
• Apps: Try Clue, FitrWoman, or your smartwatch’s built-in cycle tracker (Garmin, Apple Health, etc). These help you spot patterns over time.
• Advanced: Add your RPE (rate of perceived exertion), sleep quality, and any unusual aches or cravings.

After a few months, you’ll see your own “training fingerprint”—strong days, off days, and how they line up with your cycle. You’ll know when to schedule your toughest sessions, and when to ease off.

Pro tip: If you have a coach, share your cycle log. Open, honest conversations mean better support and smarter training plans.

Adapting Your Ultra Marathon Training Plan

The best training plan is flexible—not rigid. Your cycle is part of who you are as an athlete, so let it help you, not hold you back.

• Build in flexibility: Plan your hardest weeks or key long runs for phases when you know you feel strong. Use your cycle tracker to “forecast” these windows.
• Have backup workouts: If a tempo day falls on a low-energy PMS day, switch it for an easy run or cross-training, and move the hard session to when you’re ready.
• Communicate: If you work with a coach, let them know what you’re experiencing. Even self-coached athletes can write notes to themselves (“expect cramps,” “aim for sleep”).
• Race week realities: Sometimes, a race lands on your period. Prepare with extra hydration, easy-to-digest snacks, and period products you trust. Don’t panic—many women run their best anyway.

Lost Pace: Consistency beats perfection. If you need to adjust, you’re not failing—you’re being smart.

Special Considerations & Advanced Topics

• Hormonal contraception: The pill, hormonal IUDs, or implants can make your cycle steadier, shorter, or even stop it. This may help you plan, but can also mask natural cues. Check with a sports doc if unsure.
• Amenorrhea and RED-S: If your period stops (amenorrhea) or cycles become irregular, this can signal low energy availability, high stress, or overtraining. Don’t ignore it—see a medical professional experienced with athletes.
• Perimenopause: For women in their 40s or 50s, cycles can change or become unpredictable. Mood swings, hot flashes, or sleep trouble can join the party. Stay on top of bone health, strength work, and nutrition.
• Travel, heat, altitude: Adventure races can make your cycle symptoms unpredictable. Hydrate more, adjust training, and don’t hesitate to rest extra if needed.

Lost Pace: No two runners—and no two cycles—are the same. Your training, your health, your rules.

❓ Frequently Asked Questions

📚 Further Reading

• The Impact of Menstrual Cycle Phase on Athletes’ Performance (Carmichael et al., 2021, MDPI IJERPH)
  Comprehensive peer-reviewed review on menstrual cycle effects on female athlete performance.
• Menstrual Cycle and Ultra-Running Performance (Muriach et al., 2021, IJERPH)
  Original research on hormones, fatigue, and recovery in female ultra runners.
• Injury Risk and Well-being During the Menstrual Cycle (Fort-Vanmeerhaeghe et al., 2023, Healthcare)
  Study on injury risk and overall well-being in female athletes by menstrual phase.
• Sports Performance and Menstrual Cycle: Fact Sheet (sportscotland, 2024)
  Simple, practical, evidence-based infographic for athletes and coaches (PDF).
• BBC Elite British Sportswomen’s Survey Results (BBC Sport, 2020)
  Report: Real stories and statistics on menstruation in elite sport.

📝 Quiz: Ultra-Endurance Training and the Menstrual Cycle

📚 Recommended Books

🎬 Recommended Videos

Final Thoughts & Takeaways

💬 Real Stories from Ultra Runners

👩‍⚕️ Expert Q&A: Training & Menstruation

📝 Printable: Menstrual Cycle Tracker & Nutrition Cheatsheet

Download this simple cycle tracking table and keep it next to your training log. By noting your cycle phase, symptoms, energy, and performance, you’ll spot patterns and train smarter month by month.

💬 Community Discussion: Share Your Experience

Every ultrarunner’s experience with training during their cycle is unique. Whether you’ve discovered a nutrition hack, battled cramps on race day, or found strength in tracking your phases, your story can help others.

• How does your cycle impact your long runs, races, or motivation?
• What’s the most helpful tip or lesson you’ve learned?
• Have you noticed any positive surprises or unexpected struggles?
• Do you use any tracking tools, supplements, or special routines?

🔬 Advanced Science Deep Dive: New Research & Hot Topics

The science of women’s endurance, performance, and the menstrual cycle is moving fast. Here are some of the most interesting and sometimes surprising findings from 2022–2025:

• Individual Variation Is the Rule: New meta-analyses (2022–2024) confirm that while hormone fluctuations affect sleep, mood, and recovery, actual endurance performance rarely drops significantly at any single phase for most women. Tracking personal patterns beats any generalization.
• Cycle-Adapted Training Works—For Some: Studies like Kubica et al. (2021) show that matching hard sessions to follicular/ovulation phases may boost training quality in “responders,” but not all athletes notice a clear difference. Flexibility in planning is key.
• Injury & Ligament Risk Remain Hot Topics: 2023 data (Fort-Vanmeerhaeghe et al.) reinforce a small but measurable spike in soft-tissue injuries around ovulation—especially in sports demanding quick changes of direction or high joint load.
• Nutrition Timing & Iron: New protocols highlight the importance of iron intake right after menstruation and strategic protein/carb combinations for maximizing recovery during low-estrogen phases.
• Hormonal Contraceptives and Performance: Large athlete surveys (BBC, 2023) show that the effect of the pill or IUD on training is highly variable. Some athletes feel steadier, others report more mood or energy swings.
• Mental Health & Overtraining: Chronic low energy or missed cycles (RED-S) remain a risk in ultrarunning. Monitoring well-being, mood, and period regularity is now part of elite health screening.
• Data Gaps: There’s still a lack of research on perimenopause, non-cisgender athletes, and the effect of ultradistance stress on hormonal health. The best advice? Keep sharing real-world data and advocate for more inclusive studies.

🦴 Menstrual Health & Long-Term Endurance

Long-term health isn’t just about finishing today’s run or hitting your next PR. For women, menstrual health is a crucial marker of energy balance, recovery, and overall endurance longevity.

• Regular cycles = robust health: A consistent, pain-free period is a sign your training load, nutrition, and recovery are all in sync. Irregular, missed, or painful periods can be early red flags for overtraining or under-fueling.
• Bone health and RED-S: Energy deficiency and chronic low estrogen can lead to bone stress injuries and even osteoporosis. Master runners and those with a history of missed periods should pay extra attention to calcium, vitamin D, and resistance training.
• Perimenopause and postmenopause: Cycles become unpredictable, hot flashes and sleep disruptions appear, and injury risk can change. Adjusting nutrition, cross-training, and focusing on strength work helps maintain endurance and vitality.
• Mental health matters: Mood swings, brain fog, and anxiety often get worse with low energy or big hormonal shifts. Community support and professional help can be game changers.
• Track your health: Period-tracking apps, annual blood tests, and regular check-ins with a women’s health specialist are vital for lifelong performance—especially for master and ultra runners.

🏅 Coach’s Corner: Supporting Female Runners

Female athletes are breaking barriers in ultra and endurance running, but their needs and physiology aren’t always the same as men’s. Here’s how coaches, partners, and teammates can help women train and race their best through every phase of their cycle.

• Normalize the conversation: Make it clear that menstrual cycles and symptoms are part of training, not an awkward topic. Simple check-ins like “How’s your energy this week?” open the door for honest feedback.
• Plan for flexibility: Encourage athletes to adjust hard workouts, long runs, or race plans around their strong and low phases. Support schedule changes—don’t see them as “excuses.”
• Track patterns, not stereotypes: Remind runners that every woman is different. What works for one may not for another. Personalize advice and encourage logging both cycle and performance.
• Watch for warning signs: If a runner reports missed periods, ongoing fatigue, or increased injuries, recommend professional support. Early action prevents long-term health risks.
• Celebrate strengths: Women often show incredible resilience and adaptation across the cycle. Recognize and praise effort—not just results.

📖 Glossary of Key Terms

Follicular Phase

The cycle phase just after menstruation, usually days 6–13, when estrogen rises and energy often improves.

Luteal Phase

The post-ovulation phase (days 15–28). Progesterone is high, body temperature rises, and PMS symptoms may appear.

Ovulation

Usually around day 14, when an egg is released and estrogen peaks. Some women feel powerful; others may notice twinges or soreness.

Menstruation

The start of the cycle (days 1–5) when bleeding occurs and hormone levels are lowest.

RED-S (Relative Energy Deficiency in Sport)

A syndrome caused by insufficient energy intake for exercise demands, leading to missed periods, fatigue, and bone stress injuries.

Amenorrhea

The absence of periods for three or more months, often a sign of low energy availability or hormonal imbalance in athletes.

PMS (Premenstrual Syndrome)

Symptoms (bloating, mood swings, fatigue, cravings) that occur in the week before menstruation due to hormonal changes.

Perimenopause

The transitional period before menopause when cycles become irregular and symptoms like hot flashes may occur.

Cycle Syncing

The practice of adjusting training, nutrition, and daily activities to align with menstrual cycle phases for optimal performance and well-being.

🚩 Challenge: Track Your Cycle & Ultra Training!

Ready to take your performance and self-awareness to the next level? Join our 30-day Ultra + Menstrual Cycle Challenge:

1. Track your period, symptoms, mood, and every workout for one full cycle.
2. Notice patterns in energy, motivation, and recovery.
3. Adjust one part of your training (rest, nutrition, key workouts) based on your cycle data.
4. Share your biggest surprise, lesson, or tip with the community—comment or tag #LostPaceUltraChallenge!