Have you ever found yourself setting personal records for 10 days straight, only to feel like you’re running or riding with lead legs the following week? Full of energy on Wednesday, but completely drained by Saturday for no obvious reason?
Spoiler alert: there is a reason. And it’s called your menstrual cycle.
For a long time, women were trained as if they were simply smaller men. The result? High-intensity sessions scheduled at the worst possible time, temporary drops in performance mistaken for personal failure, and plenty of frustration. Fortunately, research has made significant progress in recent years.
Today, we know that understanding your cycle is a powerful training tool. It’s not an excuse or a limitation—it’s a genuine advantage. In this article, we’ll explore the four phases of the menstrual cycle, how each one affects your performance and recovery, and, most importantly, how to adapt your cycling or running training so you can work with your body, not against it.
The 4 Phases of the Menstrual Cycle: A Quick Overview
The average menstrual cycle lasts 28 days, although anything between 21 and 35 days is considered normal. It can be divided into four main phases.
Phase 1 — Menstrual Phase (approximately Days 1–5)
This is when your period occurs. Estrogen and progesterone levels are at their lowest. Many women experience fatigue, cramps, or headaches during this phase. Others, however, start feeling great again as early as the second or third day. Every body is different.
Phase 2 — Follicular Phase (approximately Days 6–13)
Estrogen levels gradually rise. For most women, this is the best window for high-intensity training. Energy levels increase, recovery improves, and motivation is often at its highest.
Phase 3 — Ovulation (around Days 14–16)
Estrogen reaches its peak. Performance can also peak during this time. However, there’s a small trade-off: increased ligament laxity may slightly raise the risk of injury during highly technical movements, such as sharp changes of direction while running, all-out sprints, or technical descents on the bike.
Phase 4 — Luteal Phase (approximately Days 17–28)
Progesterone becomes the dominant hormone. For many women, this is the most challenging phase of the cycle. Increased fatigue, lower heat tolerance, water retention, mood swings, and food cravings are common. Premenstrual syndrome (PMS) often develops during the last 5 to 7 days before the next period.
Why These Phases Really Affect Your Performance?
Estrogen and progesterone are far from “neutral” hormones when it comes to athletic performance. They have a direct impact on several key physiological functions:
- Energy use: During the follicular phase, when estrogen is higher, your body relies more efficiently on carbohydrates, making it an ideal time for high-intensity efforts. During the luteal phase, when progesterone is higher, your body shifts toward using more fat as fuel, which can benefit moderate-intensity endurance sessions.
- Recovery: Recovery tends to be faster during the follicular phase and slower during the luteal phase.
- Body temperature: During the luteal phase, body temperature increases by around 0.3 to 0.5°C (0.5 to 0.9°F), making workouts in hot weather feel significantly more demanding.
- Inflammation: Inflammation may be more pronounced during the luteal phase, increasing the sensation of muscle soreness after training.
All of this helps explain why you can set a personal best one week and struggle through an easy run or ride the next, even though nothing has changed in your training plan. It’s not all in your head, and it’s certainly not a lack of motivation—it’s simply physiology.
How to Adapt Your Training to Each Phase of Your Cycle?
The goal isn’t to plan every workout rigidly. It’s to think big and adjust as needed: schedule your toughest sessions during the most favorable phases and adapt the intensity whenever your body tells you to.
During Your Period: Listen to Your Body
Exercise if you feel like it. In fact, physical activity can help relieve menstrual cramps by improving blood flow and triggering the release of endorphins.
Choose easy endurance rides, relaxed runs, or short 30- to 45-minute sessions. Avoid very high-intensity workouts if you’re feeling particularly fatigued, but if you feel good, don’t hold back.
Tip: Start gently and increase the effort based on how you feel. Many women notice that things improve after 15–20 minutes of warming up.
Follicular Phase: Your Golden Window
This is the best time for your hardest workouts of the week: intervals, VO₂ max sessions, threshold workouts, or demanding long rides and runs.
Take advantage of this period to push yourself a little more than usual. It’s also the ideal time to aim for a personal best, whether it’s an FTP test, a 10K time trial, or an ambitious long ride. Since recovery is generally faster, you may even be able to schedule two hard sessions with only one recovery day in between.
Around Ovulation: Strong Performance, With a Little Caution
High-intensity workouts are absolutely fine, but be careful with explosive changes of direction or highly technical terrain.
If you’re a runner, consider avoiding very technical trail runs during this period. If you’re cycling, there’s generally no reason to worry—it’s actually an excellent time to chase a new performance goal.
Luteal Phase: Adapt, Don’t Give Up
This is the phase where strategy matters most—not resignation.
Focus on moderate endurance workouts: long Zone 2–3 rides, easy runs, or sustained efforts that stay below your maximum intensity.
Instead of skipping interval sessions altogether, simply reduce the intensity. For example, train at around 80% of your VO₂ max power instead of 90%.
If your PMS symptoms are significant, don’t hesitate to take one or two complete rest days during the three to four days before your period. You’re not losing fitness—you’re allowing your body to recover more effectively.
Drink more water than usual. Water retention doesn’t mean you need less hydration—quite the opposite. Also, avoid training in very hot conditions whenever possible, as your heat tolerance is reduced during this phase.
Special Cases: Birth Control, Hormonal IUDs, and Irregular Cycles
If you’re taking the contraceptive pill or using hormonal contraception (implant, hormonal IUD, etc.), you don’t experience a “natural” menstrual cycle. Hormonal fluctuations are much smaller, meaning their impact on performance is also less pronounced.
That doesn’t mean you’ll feel the same every day. It simply means the fluctuations are more subtle, so it’s better to rely on how you feel than on the calendar.
If you have an irregular cycle—because of PCOS, perimenopause, or naturally unpredictable cycles—tracking by dates is often less useful. Instead, pay attention to how you feel during similar workouts. Your perceived effort is often the most reliable indicator of your current fitness.
👉 If you’d like to take your training even further, check out our article Training Data Analysis: Which Metrics Should You Track to Really Improve? It perfectly complements listening to your body’s signals throughout your cycle.
How Kinomap Helps You Train With Your Cycle?
One of Kinomap’s biggest strengths is its complete flexibility.
During the follicular phase, choose a demanding mountain route, a legendary climb, a community challenge, or an intense interval workout. This is your time to push your limits.
During the luteal phase, opt for flatter routes, scenic coastal rides, or peaceful Scandinavian landscapes. The workout is still effective, but the intensity naturally decreases.
During your period, enjoy a gentle 30- to 45-minute ride on a route you simply enjoy, with no pressure to perform.
You’re no longer dependent on the weather—or the cold—to adapt your training to your energy level. Every morning, you can choose exactly the workout your body needs, and it’s ready whenever you are.
And What About Mental Well-Being?
The luteal phase also calls for a little more self-compassion.
If you’d like practical tools to help you navigate these more challenging days, take a look at our article Build a Champion’s Mindset: Tips and Exercises to Improve Your Mental Resilience in Cycling and Running.
Common Mistakes to Avoid
- Trying to do exactly the same workout throughout the entire month. Your body isn’t linear, and your training plan shouldn’t be either.
- Feeling guilty about a difficult workout during the luteal phase. It’s not a failure—it’s valuable information.
- Ignoring your body’s signals. Fatigue, poor sleep, irritability… these aren’t weaknesses; they’re useful feedback.
- Thinking that cycle-based training is just an excuse to train less. In reality, it helps you train more effectively at the right times.
- Comparing your cycle to someone else’s. Every woman is different, and your best performance window may shift by one or two days compared to the average.
How to Track Your Cycle?
Use a cycle-tracking app such as Clue, Flo, or Garmin Connect to identify your different phases.
After each workout, record a few simple observations:
- Your energy level (rated from 1 to 10)
- Sleep quality
- Motivation
- How the workout felt overall
After two or three cycles, you’ll begin to recognize your own personal pattern. That’s when things become truly powerful: you’ll know exactly when to schedule your toughest workouts and when it’s smarter to ease off. No more surprises. No more unexplained frustration.
Conclusion
Your menstrual cycle is not an obstacle to progress—it’s a tool, provided you learn how to use it.
The follicular phase is the ideal time to push harder and take advantage of your increased energy. As you enter the luteal phase, keep your training volume but reduce the intensity. During your period, listen to your body and adjust your workouts accordingly. Above all, observe how you feel.
Adapting your training to your cycle means stopping the fight against your body and starting to work with it. That’s often the difference between making average progress and reaching your full potential.
The female body is unique, with its own natural rhythms. Respecting those rhythms is one of the smartest ways to become a stronger athlete.
By Fanny Marre
Cycling, running and triathlon coach
fannymarre99@gmail.com
See previous coaching articles:
HOME AND INDOOR SPORTS: BOOST YOUR PERFORMANCE
BEST TIME TO WORK OUT: MORNING OR EVENING?
WEIGHT LOSS: WHY INDOOR CYCLING PROTECTS YOUR JOINTS