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Life is filled with natural rhythms: the seasons of the year, the rising and setting of the sun, the ocean’s tides. And women have their own internal rhythm, too.
It’s called the infradian rhythm, and it’s the monthly cycle of your hormones. These hormones impact many things about your physiology, including your nutrient requirements and how you respond to workouts.
If you’ve never heard of it, don’t worry. The infradian rhythm doesn’t get a lot of attention. Most women just think of their cycle as bleeding and non-bleeding days—and if you’re trying to get pregnant, maybe you think about ovulation as well.
(No shame if that sounds like you – most of us are taught NOTHING about the infradian rhythm!)
The truth is, there are actually four distinct phases of your monthly cycle, and each one has specific effects on your physiology. Not only does your infradian rhythm impact how you feel each month, but it also impacts how your body responds to certain inputs.
What is Cycle Syncing?
Cycle syncing is adapting your life inputs, such as food, exercise, and even work deadlines, to your menstrual cycle to support your health and proper hormone function. Ultimately, cycle syncing can help improve how you feel, look, and perform long-term. It’s an incredible strategy for regulating your periods, optimizing fertility, and reducing negative symptoms typically associated with your period, such as PMS/PMDD, cramping, and fatigue.
Intrigued? Buckle up, because today you’re getting a crash course in your own biology and cycle syncing!
PS: I’ve written two additional in-depth articles about cycling syncing your diet and cycle syncing your workouts. Make sure to check those out after you’ve gotten all the knowledge about cycle syncing in this article!
Getting To Know Your Cycle
Your menstrual cycle has four phases. While the following days are set to a 28-day cycle, the exact days may vary slightly for you as there’s definitely a range for what is considered to be normal when it comes to overall cycle length.
Phase 1: Menstrual, this phase starts on day 1 of your period and can last anywhere from 3-6 days.
Phase 2: Follicular, begins after menstruation, typically ends around day 12.
Phase 3: Ovulatory, occurs around days 13-16 of your cycle. This phase lasts 3-4 days.
Phase 4: Luteal, roughly days 17-28. This phase occurs after you ovulate, and ends right when you start menstruating.
During each phase, hormone levels change and that changes how you feel: your energy level, mood, appetite, exercise recovery, stress response, and even your pain tolerance can be affected.
Today, I’m going to cover each phase, and how it impacts how you feel. Read this post first before jumping into my in-depth posts about Cycle Syncing Your Fitness: How to Exercise During Each Phase of Your Menstrual Cycle, and how to eat to support your cycle (coming soon!).
Tracking Your Cycles
To figure out your own personal cycle length and understand what phase you’re in, you need to track your cycles. The days of each cycle listed above are just estimates. Your phase length will be unique to your cycle.
Regular tracking is important because even women with normal cycles can see variation month to month. Plus, many women have irregular cycle lengths because of issues like stress, hormone imbalance, and PCOS.
The first marker to track is the first day of your period each month. When your period ends, you menstruation phase is complete and you enter the follicular phase.
To figure out exactly when your ovulation phase begins and ends, you will need to track your basal body temperature and changes in cervical mucus each day. Don’t be intimidated! This is actually much easier than you’d expect.
As outlined in Taking Charge Of Your Fertility, once ovulation occurs, you experience a significant rise in your Basal Body Temperature (BBT). This rise is typically 0.4 degrees Fahrenheit, and the temperature shift is sustained until menstruation starts over again. The day just before this temperature shift is the day you ovulated.
As a secondary marker, your cervical fluid changes in the ovulation phase, including right before ovulation occurs. As an egg starts to mature, your cervical fluid will increase. Right before you ovulate, it becomes more clear and slippery, similar to the consistency of egg whites.
To track your temperature shifts, you simply take your BBT each morning at the same time before getting out of bed with a basal thermometer. You can track your temperature changes on a printable chart, which also includes space to note changes in cervical fluid.
Once you have a clear picture of when you’re ovulating, you can make the distinction between the ovulation phase and luteal phase and begin cycle syncing.
Can I Start Cycle Syncing If I Don’t Have A Period?
If your period is MIA because you’re on the birth control pill (even if you bleed monthly, that is not the same as a period), it means your hormones are suppressed by the pill. You won’t have the same hormonal changes with your cycle. Save cycle syncing for when you’re off the pill. (Thinking about stopping? See this article for tips for quitting the pill.)
If you’re not pregnant or on the pill, and you don’t have a regular period, the first thing you should do is check in with your doctor. Hormonal imbalance like PCOS (polycystic ovarian syndrome) or hypothalamic amenorrhea (HA) could be the root cause.
That being said, if your doctor recommends starting the pill to “get your period back,” it won’t address the underlying root issue. The pill works by suppressing your body’s natural hormones and replacing them with synthetic ones, which means when you stop the pill, any underlying issues will still be there. Instead, I recommend addressing the underlying cause of your missing period so that you can get your period back and enjoy all the benefits of cycle syncing.
To begin cycle syncing, you first need to work on getting your period back. It is possible to get your period and balance hormones naturally! If you suspect you have hypothalamic amenorrhea, check out How to Get Your Period Back. If you have PCOS, check out Root Causes of PCOS and Treating Hormonal Imbalances Naturally with Melissa Grove, RDN, LD.
Can I Start Cycle Syncing If I Have Irregular Periods?
In short, yes you can! You will need to track your cycles and shift what you’re doing based on what phase you’re in.
While you implement cycle syncing with irregular periods, it’s important to also work on any underlying causes of your irregular periods. Typically this is caused by certain hormonal balances, mainly estrogen dominance and low progesterone. To get your hormones back into balance, check out How to Reverse Estrogen Dominance Naturally.
How it Works: The Beginner’s Guide to Cycle Syncing
Phase 1: The Menstrual Phase
What Happens: Progesterone drops (and as a result, so does your Basal Body Temperature) and triggers the body to start shedding the endometrial lining. You start your period!
Your physiology: Your hormones levels, including both estrogen and progesterone, have dropped.
How You Feel: Right at the start of this phase is typically when your energy levels are lowest for the month. You might feel inclined to take some additional rest time and sleep more. Intense workouts are less appealing, and aerobic efforts are ideal. This is a very introspective and thoughtful time, because the low levels of hormones improve communication between both sides of the brain. This is a good time to evaluate, synthesize, and review. What can you learn, and how might you do things better in the future?
Phase 2: The Follicular Phase
What Happens: This phase begins as soon as your period ends. An interesting idea about this phase from Alisa Vitti, author of In the Flo, is that this should actually be considered the first phase of the cycle, with the menstrual phase coming last. But, because Western doctors count day 1 of your period as day 1 of your cycle, we’ll continue calling this phase 2.
Your physiology: Estrogen slowly increases, peaking just before ovulation. Your hypothalamus sends FSH (follicle stimulating hormone) to your ovaries to help mature eggs.
How You Feel: The follicular phase is a time of new beginnings. You’re open to new ideas, creativity peaks, and it’s a good time to brainstorm and set intentions for the future. Have a project to start? This is the time to do it. Your immune system is also high functioning at this time, so you’re less likely to get sick.
Hormonal changes slow down your metabolism, so cravings are lower, and continue to stay low through the ovulatory phase. You’re also more insulin sensitive during this phase due to the increasing levels of estrogen. As a result, carbohydrates are used more efficiently, which is great for fueling high intensity workouts.
Phase 3: The Ovulatory Phase
What Happens: Your body release an egg into the fallopian tubes and down into the uterus, where your uterine lining has rejuvenated during the follicular phase.
Your physiology: Estrogen and luteinizing hormone (LH) both peak to stimulate the release of an egg. Your fertility peaks just before you ovulate, so if you’re trying to conceive, this is the time to go for it.
How You Feel: Even though this phase is short, hormone changes are dramatic, so you might notice a dramatic change in how you feel, too. Typically, your energy is at its peak in this phase. You feel more social, and feel more inclined to get out of the house and be around others. High intensity workouts are ideal, both because motivation and energy are high, but also you’re most insulin sensitive during this phase.
Collaboration and communication skills peak during ovulation too, so it’s a good time to work with others on a big projects. Your immune system remains revved by estrogen levels being high as well, which keeps you strong and less likely to get sick.
Phase 4: The Luteal Phase
What Happens: In this phase, progesterone rises (hence that shift upward in your Basal Body Temperature), priming the uterus for the arrival of a fertilized embryo.
Your physiology: This phase is when progesterone peaks. Estrogen also rises slightly. Then, hormone levels drop to their lowest levels right before your period starts. This downward shift is responsible for the symptoms of PMS/PMDD some women experience.
How You Feel: The first half of the luteal phase is great for getting things done. You might have better focus for detail-oriented tasks as well. Put organizing, home administration tasks, and finishing up projects on your schedule. Your body is less insulin sensitive during this phase, so it’s a great time for strength training and aerobic efforts.
Your immune system slightly downshifts (to prevent the immune system from potentially attacking a fertilized embryo), but energy expenditure (your metabolism) increases 8-16%. That means you don’t just FEEL hungrier, your body is actually burning more fuel and requires more calories—250-300 calories more on average! During this phase, your body’s stress response is also heightened and you release more cortisol in response to stress. This makes stress management techniques crucial during this time.
Once hormone levels drop, so does your energy levels. When that happens, it’s time to scale back. Once your period starts, refer back to phase 1!
Our Cycle Is A Gift
What I love about cycle syncing is it turns each phase of the cycle into a gift. Your period is not a “curse”, it’s the right time of the month to relax, recharge, and reflect. And there’s a phase for just about everything: from when you’ll want to get after it in the gym, to when you’ll want to eat more comforting foods and chill out on the couch.
Want to dive deep into how to sync your food and exercise to your cycle? Check out my in-depth articles Cycling Syncing: What to Eat in Each Phase of Your Menstrual Cycle and Cycle Syncing Your Fitness: How to Exercise During Each Phase of Your Menstrual Cycle.
Instead of trying to “power through” our cycle, we can lean into it, embrace it, and use it to make our lives run more smoothly. It’s pretty darn cool. And once you go with this flow, you’ll notice improvement in how you feel, your hormones, and your overall health.
Have you tried cycle syncing? How has cycle syncing helped you balance hormones and improve your health? Share with me below!