If you have a menstrual cycle, you might notice changes in how you run, ride, row, or lift at different times of the month. Your cycle is “driven by predictable hormonal shifts, and those changes can influence how your body feels and performs,” says Li-Shei Lin, MD, a reproductive endocrinologist and OB/GYN at Reproductive Partners Fertility Center – San Diego.

Everyone is different, and while some people notice shifts in energy or mood at certain points in their cycle, others don’t experience these changes. But it is possible for hormone fluctuations to trigger changes in how you perform in your workouts throughout the month. By keeping tabs on how you feel from day to day and week to week, you can adjust your fitness routine as needed to optimize performance and feel your best.

“You don’t need a brand-new workout plan every week, but understanding these patterns can help you take advantage of the days when you naturally feel stronger and give yourself more grace on days when your body is asking for [it],” Dr. Lin says.

Many variables can impact your menstrual cycle and its length, including age, birth control methods, and whether you’ve recently had a baby. But if you’re experiencing changes in energy or mood at certain points in your cycle, the strategies below may help. Just remember that while it’s possible your experience aligns with what’s described here, it could also be the total reverse. The key takeaway is to listen to your body and do what feels right for you.

How Might Your Menstrual Cycle Impact Your Fitness Routine?

The menstrual cycle is a “dynamic hormonal symphony,” says OB/GYN Christie Cobb, MD. These hormonal fluctuations can impact different aspects of the body, she explains, from mood to muscle development. As a result, it’s possible (though definitely not guaranteed) to feel a little differently when exercising at certain times of the month.

Again, everyone is unique, but when it comes to exercise, your menstrual cycle could influence your energy levels in particular, says Heather Irobunda, MD, a board-certified OB/GYN and former member of Peloton’s Health and Wellness Advisory Council. “You may notice that you enjoy more intense workouts during the first two weeks of your cycle and during ovulation,” she says. “You may also notice that you have a harder time during the last two weeks and want to schedule more rest days during that part of your cycle.”

Listening to your body and building in rest is always key, but there’s also no reason to skip your workouts or exercise any differently in this second half of your cycle if you feel just fine. In fact, the American College of Obstetricians and Gynecologists (ACOG) recommends regular aerobic exercise to reduce symptoms like fatigue and depression that you may experience during this time. 

“There isn’t a point in the cycle when exercise is contraindicated, despite many myths surrounding menstruating,” Dr. Cobb says.

How Different Menstrual Cycle Phases May Affect You

The average menstrual cycle is about 28 days, according to ACOG, and has distinct phases. Here’s how you might feel when exercising during each.

The Follicular Phase

The follicular phase overlaps with the menstrual phase and starts on day one of your cycle, or the first day or menstrual bleeding when the uterine lining sheds. “I think of the follicular [phase] as the ‘full out’ phase because hormonally, estrogen levels begin to rise as the follicular development progresses towards ovulation,” Dr. Cobb says. This phase of the cycle is the longest, lasting somewhere between 14 and 21 days for most people, according to the Cleveland Clinic. 

Since the start of the follicular phase aligns with the start of your period, you may feel bloated, moody, or experience headaches at the onset. Exercising might be the last thing you want to do if you’re experiencing symptoms like these, but working out may help you feel a little better. As long as your symptoms aren’t debilitating and you feel up for it, moving your body could help.

Speaking of energy: While you might feel more tired at the start of your period, your estrogen levels gradually increase during the follicular phase, which may in turn lead to increased feelings of energy. “As estrogen rises, many people feel more energized,” Dr. Lin says. “This is often the phase where strength training, interval workouts, and higher-intensity exercise feel more doable because estrogen supports muscle performance and recovery.”

Research has shown increased muscle strength when doing strength training at this time of your cycle, adds Dr. Irobunda. “During the first two weeks of your menstrual cycle, you may feel stronger during your workouts.” So grab your weights and get those reps in, if you feel up for it. (Peloton has tons of strength training classes that can help you get started.)

Ovulation

In a typical 28-day cycle, ovulation happens around day 14, right in the middle, and lasts for about 24 hours. In this phase, a surge of estrogen and sudden release of luteinizing hormone (LH) allows an egg to be released from the ovary. (The exact timing varies, however—if your cycles are shorter or longer than 28 days, ovulation could be sooner or later than day 14.)

Just before ovulation, there’s a physiologic temperature spike, Dr. Cobb says, “which some women may notice makes them less tolerant to heat.” If this describes you, you may want to avoid really sweaty workouts for a day or two, such as hot yoga or outdoor exercise in warmer weather.

“There can be a burst of energy during this time, which may cause better athletic performance,” Dr. Irobunda adds. “Many see great athletic performance with high-intensity workouts.” Now might be the time to take HIIT classes, interval runs, Power Zone Rides, and Bootcamps.

The Luteal Phase

The last two weeks of your menstrual cycle make up the luteal phase. Here, progesterone and estrogen levels rise and then fall, eventually triggering the start of your next period. This phase is when premenstrual syndrome (PMS) may appear, possibly bringing on fatigue, gastrointestinal symptoms, food cravings, mood swings, and insomnia. 

“I think of luteal as the ‘laid back’ phase, when lower-intensity exercise and lighter weight training may feel more natural,” Dr. Cobb says.

Why? Progesterone becomes the dominant hormone after ovulation, Dr. Lin says, which “slightly raises your core body temperature, which can make intense or heated workouts feel harder.” 

Your body’s going through a lot in these two weeks, so give yourself permission to take a break. Hydration becomes especially important in the luteal phase, Dr. Lin adds, and it can help to build in more rest days. “You are more likely to feel like taking a day off in the last two weeks of your cycle because of hormonal changes,” Dr. Irobunda says. “There may be more days during this cycle that you feel tired and want to do less intense workouts.”

On days when your energy is low or you’re dealing with PMS symptoms, Dr. Irobunda recommends adding yoga and meditation classes to your exercise routine, both of which provide mental and physical benefits. Pilates and barre, which are gentler on your body, are good options too. (You can find classes in all of those modalities on the Peloton App, by the way.)

Some people also experience bloating or breast tenderness during this phase, so choosing activities that feel supportive and comfortable if you’re having symptoms like those is smart, Dr. Lin says. But if your personal best remedy is a full-out sweat session with the volume cranked up, the good news is that those classes are just a few taps away too.

Remember That Every Person Is Different

While some people will experience the changes above throughout their menstrual cycles, others may not notice any difference from day to day or week to week. But some people might find that understanding the physiology behind their cycle helps them better tune into what their body needs.

“Movement supports your health in every phase,” Dr. Lin says. “Even low-impact movement can deliver meaningful benefits for your physical and emotional wellbeing. The most important principle is flexibility. Your cycle changes week to week, and your fitness routine can adjust right along with it.”

Most importantly, listen to your body—if you have symptoms like severe cramps, dizziness, fever, unusually heavy bleeding, or pain that makes it difficult to exercise at any point in your cycle, make time to rest and check in with your healthcare provider.