Are Cycle-Syncing Workouts Legit? Here’s What the Science Says

Lauren Mazzo
·10 min read

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If you get a period, you may have noticed that your body feels…different…at various points in your monthly cycle. Some days, you might feel charged up and ready to go, while others you’re moving in slow motion. It would make sense that this ebb and flow might impact how you show up to tackle your fitness routine too. That’s the idea behind cycle-syncing workouts, or the practice of changing up your exercise routine according to what phase you’re at in your menstrual cycle.

In theory, it seems solid: If hormones change throughout the month, why shouldn’t your workouts? Advocates of the practice say it comes with a range of benefits, from improving performance and recovery to decreasing cycle-related symptoms and fatigue. Some professional athletes (like Ironman World Champion Laura Philipp) have spoken publicly about factoring their cycle into training, and even the US Women’s National Team, led by sports scientist Dawn Scott, famously leveraged it en route to their 2019 World Cup win. Over the last few years, the concept has become a trendy wellness topic, even prompting dedicated cycle-syncing apps, workout programs from Nike, Obé, and Alo Moves, and tens of thousands of posts on TikTok.

The thing is, the science isn’t quite there, and as a result experts aren’t exactly jumping to endorse it. Curious about cycle syncing? Here’s everything you need to know.

What a cycle-synced workout routine might look like

The menstrual cycle can be divided into two main phases: follicular, the first half of the cycle when you menstruate and an ovary gets ready to release an egg; and luteal, the second half when your body prepares for a potential pregnancy. Ovulation is essentially the turning point in between, Janet Choi, MD, a double-board certified reproductive endocrinologist and ob-gyn and the chief medical officer of Progyny, tells SELF.

In the context of cycle syncing, many people break the menstrual cycle down into four distinct parts: menstruation, follicular, ovulation, and luteal. Cycle-based workout routines hinge on the changes that happen during each phase to guide exercise intensity throughout the month. Because the method isn’t yet supported by a lot of science, the recommendations on how to sync your workouts to your cycle vary. In general, proponents of the practice suggest something like this:

Menstruation (~Day 1–5): Light workouts like walking, stretching, mobility, and active recovery. Menstruation (i.e., your period) happens at the beginning of the follicular phase, and it’s characterized by low hormone levels, particularly estradiol (a type of estrogen), Dr. Choi says. As a result, during this time, you may experience fatigue and decreased energy. You may also deal with period-related symptoms like cramps, nausea, or headaches, which could keep you from wanting to do high-intensity workouts or going all-out in the gym.

Follicular (~Day 5–14): Moderate-to-high-intensity workouts, like running, dance cardio, or weight lifting. After your period ends and the follicular phase progresses, estradiol levels slowly rise, Dr. Choi says. You might find yourself with more and more energy as you approach ovulation, making it a potentially good time to ramp up your workout intensity.

Ovulatory (~Day 14): High-energy or strenuous workouts, like running, dance cardio, or weight lifting. Hormone levels, including estradiol, peak around ovulation, Dr. Choi says. At this point in the cycle, many menstruators notice increased energy, improved mood, and heightened creativity, she says—in theory, making it a great time to challenge yourself and go for that PR.

Luteal (~Day 14–28): Somewhat gentler exercise, like Pilates, yoga, walking, or steady-state cardio. “Following ovulation, estrogen levels start to decline while progesterone levels rise, peaking about a week post-ovulation,” Dr. Choi says. During this phase—and especially as you approach your next period and deal with potential PMS symptoms—you may experience lower energy, sleep disturbances, and possible mood changes, Dr. Choi says. For this reason, you may feel like dialing back on your workout intensity at this time.

An important caveat: Though a 28-day cycle is considered “typical,” menstrual cycles can vary from person to person and month to month. In fact, one 2019 study of more than 600,000 menstrual cycles found that only 13% were 28 days long and that, for the majority of menstruators, ovulation didn’t occur on day 14. Not to mention, if you use hormonal contraception, these same fluctuations don’t apply since it interrupts normal hormonal cycling, Liz Joy, MD, MPH, FACSM, chief medical officer of Lore Health and past president of both the American College of Sports Medicine and the Female and Male Athlete Triad Coalition, tells SELF.

For some exercisers, cycle syncing is less about following a strict plan and more about tuning into your body’s needs. Meaghan Moran, a holistic health coach and personal trainer, for example, tells SELF that she’s been cycle syncing for about two years. She doesn’t follow a firm schedule but says she’s become aware of how each phase impacts her mood, body, and mental capacity and lets that guide her workouts. She prioritizes gentler movement during menstruation and the late-luteal phase while increasing the intensity as she gets closer to ovulation.

How legit are the benefits?

Some people on social media who cycle sync their workouts anecdotally say it’s helped them with everything from acne and PMS symptoms to reducing inflammation, “balancing” hormones, and seeing more significant workout results. Sounds awesome, right? But it’s important not to oversell the method’s impact because, right now, we just don’t have the research to validate these or any other potential benefits.

“Though there may be some rationale for the approach, it’s not supported by current high-quality evidence,” Sara Rosenkranz, PhD, exercise physiologist and associate professor in kinesiology and nutrition sciences at the University of Nevada, Las Vegas, tells SELF.

In fact, from a workout performance perspective, most research suggests that the menstrual cycle doesn’t significantly impact muscle strength or endurance, Dr. Choi says. Two recent reviews—one published in Frontiers in Sports and Active Living and another in Sports Medicine—analyzed the available studies on the topic and concluded that there isn’t enough evidence to support the idea that monthly hormone fluctuations affect acute fitness or long-term training results. And any actual observed difference likely isn’t dramatic enough to warrant changing your whole workout routine if you’re not a pro athlete. “Since any potential gains related to menstrual cycle training are relatively small, this is more likely to benefit elite athletes, where seconds count, to a greater extent than recreationally active women,” Dr. Joy says.

All that said, even if factoring your cycle into your workout routine doesn’t magically help you gain muscle or run a faster 5K, it could come with other perks, like making you feel good or fostering a more intuitive relationship with fitness. “Becoming more attuned to menstrual-cycle-related symptoms and how they affect and interact with physical activity is important,” Dr. Joy says. At a minimum, it gives you the opportunity to adjust your training type or exercise intensity, but it may also encourage you to modify other behaviors that support training, like diet, hydration, and sleep.

Moran, for example, used to do primarily high-intensity workouts and was left feeling exhausted. Since switching to cycle syncing, she says she’s felt a deeper connection to her body and has learned to focus on workouts that make her feel her best—even if they’re more low-key than she was used to. “I started slow by just doing walking, stretching, or yoga during my period and felt how positively my body reacted to the break during that time of the month,” she says. With cycle syncing, she has noticed an improvement in her PMS and finds that she’s “less irritable before and during menstruation.”

Are there any downsides?

Cycle syncing isn’t likely to cause any real harm, but there are a few potential drawbacks. First, “we certainly do not want to imply that people should limit their physical activity during certain phases of the menstrual cycle,” Dr. Joy says—especially considering less than a quarter of US adults get enough exercise according to federal guidelines. If you follow the above cycle-syncing recommendations, you might find it’s difficult to meet the recommendations set by the Physical Activity Guidelines for Americans, which call for 150 minutes of moderate-intensity physical activity and at least two days of muscle-strengthening work per week.

To that point, the generic cycle-syncing script could also lead you to skip out on workouts or reduce intensity when you don’t need to. “It’s well-established that exercise can be safe and effective at any point during the menstrual cycle,” Dr. Rosenkranz says.

Plus the additional layers of tracking and planning could make this approach to training feel overly complicated, Dr. Rosenkranz says. Maybe even enough so that it messes with a well-established fitness routine that’s been working for you. The reality is that it can already be difficult to squeeze consistent workouts into a busy schedule, fit in the ideal mix of strength, cardio, and mobility work, and progress toward goals like running a marathon or building muscle. Adding cycle syncing on top of this can be unrealistic or make your fitness routine feel like more of a chore than it should be.

How to try cycle syncing

The single most important thing to consider when choosing an exercise program is that it’s specific to your individual needs, Dr. Rosenkranz says. If you want to give cycle syncing a go, follow these steps to tailor it to you.

1. Start by tracking your menstrual cycle.

First, you’ll need to start tracking your cycle using a period tracking app or other method, Dr. Joy says. (If you’re not comfortable putting your information into an app, you can use an old-fashioned paper calendar or journal.) Don’t just mark the days of your period; also take note of symptoms and energy levels throughout a few entire cycles to gain insight into how the phases may affect your training, Dr. Rosenkranz says.

2. Play with your workouts and see what happens.

Start experimenting with workout adjustments based on the info you’ve collected during the last few cycles, noting how you’re feeling (energy, mood, motivation) and performing (i.e., strength or endurance), Dr. Joy says. Over time, you might notice that you struggle with high-intensity workouts the day before your period or that moderate cardio feels great at any time of the month. Rather than basing your routine around your cycle, use what you’ve learned about your cycle to modify your workouts as needed.

3. Consider other lifestyle habits.

In addition to the changes that happen with your menstrual cycle, many other factors can impact your workout experience and performance. “For example, sleep can have profound effects on training, as can nutrition and where you are in your training program,” Dr. Rosenkranz says. Your goals, stress levels, injuries, and illnesses are all other reasons that you may need to modify your workouts day-to-day. “Listening to your own body—especially signs like energy levels, mood, and physical comfort—is often the most effective way to guide workout adjustments,” Dr. Choi says.

The takeaway on cycle-syncing workouts

If you’d like to use your menstrual cycle to guide your workout programming, that’s your prerogative. It could help you gain awareness of how monthly changes affect your motivation and performance or encourage you to scale back when you need it. The potential risks are that universal cycle-syncing advice may not take your individuality into consideration, and it could unnecessarily complicate your planning or keep you from your full training potential.

Cycle syncing isn’t a cure-all, and it’s essential to be skeptical of anything with purported benefits that sound too good to be true. Still, there’s some real value at the heart of it: When it comes to working out, listening to your body and honoring its needs is always a winning approach.

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Originally Appeared on Self

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