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Decreased energy/lethargy

Feeling low in energy, lethargic or tired can be caused by many factors, including your menstrual cycle and changes in hormone levels.

What phase of your menstrual cycle do you experience decreased energy?

Low energy levels and increased tiredness can be experienced during the late luteal phase, before your period and during the first few days of a period. Some individuals also experience a dip in energy around ovulation whereas others have increased energy at this time.

Causes of menstrual cramps

Increased perceptions of fatigue during the early follicular and late luteal phases could be due to reduced levels of serotonin associated with the decline in oestrogen.

Before a period, oestrogen and progesterone levels decrease rapidly, these hormones also interact with a neurotransmitter – serotonin, which plays several roles in your body (happiness, mood, regular body temp and hunger), one of which includes decreasing energy levels and affecting sleep. 

Another reason for lethargy or feelings of fatigue is linked to inflammation as progesterone decreases – with this type of fatigue symptoms feel similar to getting ill, maybe a sore throat. 

Sleep disturbances are common during the luteal phase which can contribute to feeling like you have lower energy levels.

A final cause of this symptom can be linked to stress, the reduction in progesterone can affect the HPA axis and worsen symptoms of adrenal fatigue – feelings of agitation or stress commonly accompany this.

How to manage decreased energy

Start by tracking your symptoms for three cycles. This will allow you to work out what is causing you to feel tired (is it lack of sleep, stress, your menstrual cycle, are you feeling ill or agitated alongside this to help work out the underlying cause).

Implement sleep strategies (refer to our sleep symptom section).

If you are unusually tired, you may want to discuss with your GP in case of low iron levels (common in females who exercise). 

Check in on your fueling and hydration: Are you fuelling enough through the day and avoiding long gaps without food? Check the colour of your urine to see if you are hydrated? 

Rest – give yourself permission to stop and allow our body to recover.

Light exercise – ideally outside – may help you feel more energised.

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