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    How your energy levels change through your menstrual cycle

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    1. What are the phases of the menstrual cycle?
    2. How do my hormones change across the different menstrual cycle phases?
    3. What’s the connection between my menstrual cycle and energy levels?
    4. How to manage low-energy days

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    Graph showing changing levels

    Going through a full menstrual cycle can be associated with all kinds of symptoms, some of which are more noticeable than others. One that you might not be aware of is changing energy levels, which can affect how you sleep, work, exercise and socialise. Read on to learn more.

    What are the phases of the menstrual cycle?

    The first thing to understand is that a typical menstrual cycle lasts around 28 days and has different phases caused by rising and falling levels of hormones: 

    • The menstrual phase  
    • The follicular phase 
    • Ovulation 
    • The luteal phase 

    The menstrual phase is when you have your period – the first day that you start bleeding is considered the first day of your cycle. Bleeding will last for two to seven days, averaging at five days for most women. 

    The follicular phase begins at the same time as your period starts and ends at ovulation, lasting around 14 days if you have a 28-day cycle. If your cycle is shorter or longer, the follicular phase will be shorter or longer. During this time the ovaries are stimulated to produce and mature an egg to release at ovulation.

    Ovulation usually occurs in the middle of your menstrual cycle, at around day 14 if you have a 28-day cycle. If your cycle is shorter or longer ovulation will occur earlier or later. This is where a matured egg is released from one of your ovaries and begins to travel down the fallopian tube towards the uterus.

    The luteal phase begins after ovulation and lasts until your period starts – the luteal phase usually lasts 14 days regardless of your cycle length. If an egg isn’t fertilised during this time, the body will start preparing for its next menstrual phase. 

    How do my hormones change across the different menstrual cycle phases?

    There are some distinctive changes in hormone levels across your cycle: 

    • At the beginning of the menstrual phase, all your hormones are at a low level – this is what encourages your uterus lining to begin shedding. 
    • During the follicular phase, your pituitary gland releases Follicle Stimulating Hormone (FSH) to encourage your ovaries to prepare an egg. At this time, your oestrogen levels begin to rise. 
    • At ovulation, your oestrogen levels peak. 
    • At the beginning of the luteal phase your progesterone levels peak. However, they will fall towards the end of the luteal phase if the egg has not been fertilised. 

    What’s the connection between my menstrual cycle and energy levels?

    When your period starts, your levels of oestrogen and progesterone are at their lowest. This is known to cause a dip in energy. If you also experience cramps, you might find that the first few days of your period are a time for relaxation rather than fast-paced activity.

    As your oestrogen levels rise during the follicular phase of your cycle, you should start to feel happier and more energised. When you approach ovulation, your oestrogen level will be at its highest. You should find at this time that your mood is good, and that you have high levels of energy.

    Post-ovulation, in the luteal phase, your oestrogen levels will start to fall as your progesterone rises. For most women, this is the most problematic part of the cycle. This is because progesterone has a “depressant” effect when compared to oestrogen, and may lead to low energy and low mood. 

    How to manage low-energy days

    Feeling tired or lacking energy is something we all experience from time to time – whether we have periods or not! In other words, your low-energy days might not always be connected to your hormones.

    However, if you notice that your low-energy days align with the relevant days of your cycle, there are some things you can do to combat symptoms.

    • Listen to your body. If you wake up feeling tired, try to avoid pushing yourself too hard with work, chores or exercise. 
    • Prioritise good sleep. Aim to go to bed and wake up at the same time each night, and practise good sleep hygiene to ensure a better night. 
    • Try relaxation techniques like guided breathing, meditation, yoga and warm baths if you’re feeling very stressed and this is affecting your sleep. 
    • Don’t skip exercise. It may seem counter-intuitive but exercise can boost your energy levels, so don’t skip it altogether – instead, swap out strenuous exercise for something gentler, like swimming or yoga. 
    • Eat regularly. Rather than having three main meals a day, you might find that eating several small meals and healthy snacks keeps you more sustained and energetic. 
    • Don’t rely on caffeine. When you feel tired, avoid overdoing the coffee and tea – this can actually disrupt your sleep and make you feel more tired. 

    If your mood and energy levels are really affected by your hormones, particularly in the run-up to your period, it’s worth speaking to your GP. There are several treatment options and lifestyle changes you can make to manage bad PMS (premenstrual syndrome) – one option is to take the combined contraceptive pill

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