The Menstrual Cycle: Training and Nutritional Considerations

You’ve just started your session, warming up well and getting the blood flowing for your main workout. The only difference today is that you feel lethargic, low energy and like you’ve got nothing to give.

You’ve done the same session the week before and felt great so what’s the difference? Your nutrition, hydration and sleep haven’t varied and you’re not feeling particularly stressed so why might this be? Simply put, it could be down to your unique female physiology.

For most of us, during the first 2 weeks of our cycles, oestrogen dominates whilst during the latter half of our cycles, progesterone dominates. In general, women have reported feeling ‘better’ when it comes to training during the first half of our cycles when oestrogen is high, but not all women will feel this way!

Before we go into how your menstrual cycle might affect your training, lets have a look at the menstrual cycle.

Menstrual cycle basics

As females, our hormones fluctuate throughout the month due to our menstrual cycle as our body is preparing for potential pregnancy. Cycle duration will vary for everyone, but for the general female population a regular cycle is between 21 and 35 days.

Historically, we used to refer to our cycles as having two distinct phases: the follicular and the luteal. However, we now know that there is a variety of hormonal milestones throughout our cycle. These are mostly referred to as the early follicular, late follicular, ovulatory, early luteal, mid luteal and late luteal phases.

The early follicular phase will begin with menstruation, aka your period, which varies in length between women but will generally last between 3 and 6 days. During this time, our hormones are fairly low and stable.

During the late follicular phase, your levels of oestrogen will increase as your egg matures. When oestrogen reaches a critical point, a hormone called gonadotropin releasing hormone will cause a luteinising hormone ‘surge’. This surge signifies the release of your egg.

After ovulation, progesterone is released in the early luteal phase alongside a small amount of oestrogen. Progesterone will then reach its peak in the mid luteal phase, accompanied by a smaller secondary peak in oestrogen levels. This prepares the body for a fertilised egg to be implanted.

If your egg remains unfertilised, progesterone and oestrogen will start to decline during the late luteal phase as the cycle prepares to start all over again!

The graph shows an estimated timeline for these hormonal peaks to occur, but the timing of ovulation and each inpidual phase can vary significantly between women.

Graph of hormone fluctuation throughout the Menstrual Cycle Phases

Does your menstrual cycle affect exercise performance?

Although there’s no clear cut yes or no, hormones do have a notable affect on our physiology so it would be safe to assume that will be some effects during our menstrual cycle.

For example, menstrual symptoms (i.e. your period) occurs when both oestrogen and progesterone levels are low and mentally we might feel a bit ‘off’ during this time. Couple this with, at times, painful cramping and we’d fully support the idea that your period can affect performance!

But famously, Paula Radcliffe broke the world record in 2002 for the fastest marathon whilst having menstrual cramps, so it can’t be that bad, can it?

How our bodies use carbohydrate and fats, our muscle activation and thermoregulation are just a few physiological factors that have the potential to be affected by our menstrual cycle but it may not be enough to actually alter how we feel and perform.

How should you workout based on your menstrual cycle?

Oestrogen and Progesterone have different roles as hormones, so this may impact the type of workout you should aim for depending on where you are in your cycle.

Oestrogen, our anabolic hormone (favours muscle building), can improve our force production whilst progesterone, our catabolic hormone (favours muscle breakdown), can impair it. Therefore, it might be a good time to chase those gains with strength training during the follicular phase when oestrogen is high and progesterone is low. Oestrogen has even been shown to reduce DOMS (delayed onset of muscle soreness)!

When looking at how we burn carbohydrates and fats, oestrogen favours the use of lipid (fatty compounds) availability in muscle, however the literature is still conflicting in support for this.

The biggest take home you should have about your menstrual cycle and your workouts, however, is listen to your body and energy levels. Forgive yourself if you aren’t performing exactly how you’d like at certain times of the month, and know there’s always another workout to try again.

Do we need to eat differently around our menstrual cycle?

During your menstrual cycle, your calorie and nutrient requirements will fluctuate due to variations in your hormones. These hormones affect not only your menstrual cycle, but also other physiological areas such as body temperature, metabolism, and appetite.

During the luteal phase of our cycle, progesterone and oestrogen are high. This means our resting metabolic rate is increased, so we burn more calories naturally during this time. The extent of this increase will vary between inpiduals as well as day to day alongside other factors such as age, genetics, illness, pregnancy, body composition and your physical activity levels. Our bodies are very clever though and it’s unlikely we will notice this increase in resting metabolic rate as naturally we tend to increase our food intake due to increased feelings of hunger.

Inpidually however, our hormones seem to have a different effect on our appetite as progesterone is thought to increase it, whilst oestrogen may actually suppress our appetite which is why changes may occur during the luteal phase.

Our insulin sensitivity also may be lower during the luteal phase which means our bodies don’t respond to insulin as well, which may contribute to certain cravings in the pre-menstruation.

Recovery is also critical for exercise and our hormones have the potential to affect this without us realising as well. Progesterone is a catabolic hormone meaning it favours muscle breakdown and can inhibit your recovery. Therefore, during your cycle when progesterone is high, it may be beneficial to consider supplementing with a little extra protein.

However, these things work both ways and during times in your cycle when oestrogen is high, we have the opposite effect. Oestrogen is an anabolic hormone meaning it favours muscle building, therefore during the follicular phase when oestrogen is high, your protein requirements may be slightly lower.

In summary, although our hormones suggest there may be differences in how we do/should eat during our menstrual cycle, a lot of the time our bodies are quite good at regulating this themselves through altering our hunger hormones to suit.

Take home messages!

  1. Our hormones differ greatly during our menstrual cycle and this could affect both physical and mental performance in positive and/or negative ways.
  2. Although the menstrual cycle has a variety of effects on our physiology and metabolic needs, not every woman will notice the effects and there is a lot of inpiduality!
  3. Power to the period! Essentially tracking your menstrual cycle could give you unique insights into how your hormones may be affecting your performance during different phases of your cycle and there’s a possibility you could use this knowledge to your advantage by working with your unique physiology!