How can exercise affect your menstrual cycle?

You may have noticed that your menstrual cycle can have an effect on your day to day life, depending on which part of your cycle you are in. Some days we may feel overwhelmed, tired and a bit emotional, while on others we’re full of energy and ready to seize the day. Your menstrual cycle can also affect both your desire to exercise and what kinds of exercise you may feel drawn to. 

There are four phases of your menstrual cycle, and each can impact how you may be feeling: menstruation, the follicular phase, ovulation and the luteal phase. During the follicular phase, you may have an increased libido, due to the high levels of oestrogen, while in your luteal phase, you may feel a bit more irritable and down and experience some symptoms of premenstrual syndrome, due to low levels of progesterone. 

Research has found, up to 90% of women experience symptoms of premenstrual syndrome (PMS), which can be as simple as moodiness or headaches for some, but so severe for others that they miss work or school. There are numerous well known benefits to regular exercise, including weight loss, increase in stamina, better sleep, strength gain, reduced stress and improved overall well being. But did you know that exercise can also affect your menstrual cycle? 

Exercise on your period has been shown to be beneficial for a number of reasons. Some women and people with uteruses experience painful cramps just before and during their period, and regular exercise can help to reduce them. The main reason believed for this is due to the endorphins and pain-relieving hormones that are released during exercise. 

This is why exercising during your period can help boost your mood and counteract the fatigue you may be feeling. This could be from something as simple as going for a walk or doing some yoga, or something more high impact like going for a run or weight lifting. As with anything else, listen to your body when exercising on your period and do what feels right for you. There are very minimal risks when exercising on your period but it may be helpful to adjust your regular routine during this time. 

Some of the risks are as minimal as struggling with endurance; research has found that women who had already ovulated but not yet started their period had a harder time exercising during hot and humid weather, while other risks are more minor, such as bleeding through your protection. When exercising it may feel like you are bleeding more than usual, but this is just caused by the body’s movement causing blood to exit the uterus faster.

If you’re keen to exercise on your period it can be helpful to take some over the counter pain relievers, which can help to ease cramps. You should also make sure you stay hydrated and, of course, remember to bring period protection with you. 

Throughout your menstrual cycle, it’s likely that your energy levels will fluctuate  due to the changing hormone levels during your cycle. On the first day of your period, your oestrogen and progesterone levels are at the lowest, and begin to gradually rise throughout your cycle. In the first couple days of your period you may feel fatigued or low on energy due to the decrease in oestrogen levels, so this may not be the best time to work out.

As a result, some may find it easier to get active and be motivated at other times of the menstrual cycle, such as, around the third week, right before ovulation, when oestrogen levels are at their peak. Tracking your cycle, your energy levels and your workouts can be a great way to know when in your cycle you are feeling your most energised.  

Over-exercising and not fuelling your body properly can cause lighter or irregular periods, or even make them stop altogether. Exercise is good for you, but suddenly starting a vigorous fitness routine and low-calorie diet puts strain on your body that can cause periods to become irregular or stop altogether. This is called ‘exercise-induced amenorrhea’, where, in response to the stress your body is under, the hypothalamus (a part of your brain) begins to stimulate the ovaries less. 

A regular period can be a sign that your reproductive health and a hormonal balance are in good shape. If your period begins to change – as a result of exercise or otherwise – it is recommended to speak to your doctor, as this can lead to more serious health problems such as anaemia or loss of bone density. 

It is sometimes common for athletes to have irregular or missed periods due to the intensity of their training programs and hormonal and bodily changes they go through, especially in preparation for performance. When thinking about team sports and female athletes, it’s not unusual to wonder – if they are following the same training programme and are constantly around each other – whether their periods sync up. You’ve maybe even wondered if your menstrual cycle syncs up with your friends. 

As far as we know, there is little to no evidence that women or people with uteruses can disrupt each other’s cycles. As the average menstrual cycle is 28 days, it’s not unlikely that your period will come at the same times as those around you sometimes. Whatsmore, you’re more likely to remember the times you and your friends do sync up than the times you don’t. 

We know that exercise can affect periods but you may be wondering how birth control, like Hana®, affects your periods. When taking a desogestrel contraceptive pill like Hana®, not everyone reacts the same. Around 20 to 30% of users may experience more frequent bleeding when starting a desogestrel contraceptive pill, while 20% of those taking pills containing desogestrel, like Hana®, may experience a light bleed a bit like a light period, or amenorrhea, where periods stop altogether. This normally subsides after a few months, but if you are concerned you may want to speak to a doctor or pharmacist for advice. 

Progestogen-only contraceptive pills like Hana® should be taken non-stop, without a break between packs. This may mean that your periods could change in frequency or that you no longer get your periods, which is one of the most common side effects when taking progestogen-only pills. As your body gets more adjusted to this, your periods may come back after a few months or they may not – it varies from person to person. It’s important to remember that no form of birth control is 100% effective and having no period could also be a sign of pregnancy. If you feel you are showing symptoms of pregnancy, you should take a pregnancy test as this is the only way to know for sure.

Hana® 75µg film-coated tablets contains desogestrel and is an oral contraception for women of child bearing age to prevent pregnancy. Always read the instructions on the package leaflet carefully.

Premenstrual symptoms — severity, duration and typology: an international cross-sectional study 

Lorraine Dennerstein, Philippe Lehert, Torbjörn Carl Bäckström, Klaas Heinemann 

Physical activity and your menstrual cycle

Office on Women’s Health  

Hana SmPC – date of last revision of text July 2021