your discount will be applied at checkout
myGP logo
your 10% discount will be applied at checkout
OFFER ENDS TODAY!

Exercise and Periods: Why More Research Is Needed

Hormones play a crucial role in women's health, so why do we know so little about the impact of periods on exercise?

woman doing push ups

Blog Homepage >>

As more and more women take up exercise, we look at how much we really understand about female hormones and the impact the menstrual cycle has on women in sport and those who exercise regularly.

Women & Exercise

A recent study has found that the number of women participating in sport or physical activity at least twice a month has increased from 17.3 in 2016 to 17.8 in 2020, showing a slow but steady increase.

A Government report on a study into physical activity found that 61.5% of women over the age of 16 were physically active. This is compared to 65.3% of men.

Yet, historically, little research has been carried out to understand how women’s hormones and their monthly menstrual cycle impact their exercise performance. The bulk of exercise research is based on men with very few studies exploring the specific needs of physically active women in relation to their hormone health (1).

Female Hormones & Exercise

We know that exercise plays an important role in all aspects of health - physically, mentally, and socially (2). However, the fluctuations in female hormones during the menstrual cycle can make it more challenging for women as hormones impact exercise performance and as well as overall wellbeing.

Nearly half of female runners in a large survey reported their menstrual cycle negatively impacted exercise performance (3).

Working Out On Your Period

Each phase of the menstrual cycle is accompanied by changes in a woman’s four main hormones – follicular stimulating hormones, leutenising hormones, oestrogen, and progesterone.  During each phase, a woman will experience different symptoms to varying degrees, from low energy, sleep disturbance, to mood changes and changes in appetite (4).

Let’s take a look at each phase in the menstrual cycle and how each phase can impact working out during your period.

woman doing child's yoga pose

Menstruation

Menstruation takes place on days 1 to 5 and is when the body sheds the thickened lining of the uterus. Oestrogen and progesterone levels are at their lowest.  There is some limited research suggesting the body utilises carbohydrates (glycogen) stores more efficiently and may help to reduce appetite. This means that women may find they have better endurance and performance in high intensity cardiovascular or strength training than they do in the luteal phase.

Follicular Phase (days 1-14):

The follicular phase happens on days 1 to 14, starting at the same time as menstruation and ends with ovulation. In the follicular phase, the ovaries are stimulated by follicular stimulating hormone (FSH) to produce follicles, with one maturing into an egg. Follicle growth also raises oestrogen and leutenising hormone (LH). Levels of FSH and LH peak prior to ovulation, and oestrogen is also highest in the follicular phase. Some research suggests that during the follicle phase women should increase their intake of carbohydrates and protein. The follicular phase could be a good time to focus on fitness.

Ovulation (days 14-15):

Ovulation is when the mature egg is released and takes place mid cycle, days 14 to 15.

Luteal Phase (days 14-28):

The luteal phase happens around days 14 to 28 and is when the follicle that the egg was released from remains on the ovary. This becomes the corpus luteum and releases progesterone and oestrogen. Progesterone levels are at their peak in this phase and thicken the lining of the uterus allowing a fertilised egg to implant. When pregnancy does not take place, the corpus luteum degenerates, progesterone levels drop, and menstruation begins.  

Some studies suggest that during this phase women should focus on increasing their intake of protein due to progesterone requiring more protein biosynthesis to thicken endometrial lining (the innermost lining of the uterus) and prepare the body for possible pregnancy (5). The body will also require a consistent intake of complex carbohydrate to meet the demands from increased metabolic rate, driven by progesterone during this luteal phase.

It is important to note that these phases are not the same for all women.

Gender Gap In Research

Despite the limited studies, we do not yet know enough about how a woman’s menstrual cycle impacts her ability to exercise and perform at her best. We urgently need evidence-based advice to help women manage the complexities of female hormone cycles (6). Continuing to apply the male blueprint for exercise, nutrition and recovery to females is not the solution.

We need the evidence to answer some simple, yet important questions:

  • How does the menstrual cycle impact exercise performance?
  • What is the best sort of exercise strategies for various phases of the menstrual cycle?

The reason for this gap in evidence is that much of the research and application of sports and exercise science is based on male physiology (7). In fact, research often actively avoids including females as their hormone networks are deemed too complicated. Yet there are differences in physiological responses to exercise between men and women, most likely due to ovarian hormones as these distinguish between the biological sex of male and female (8).

Despite it being relatively straight forward, in theory, to show how oestrogen and progesterone impact exercise performance during different phases of the menstrual cycle; studies have failed to identify a cause-and-effect correlation.

Numerous studies looking at the effects of the menstrual cycle on a variety of exercise elements, very surprisingly, found no significant effects of menstrual phases on exercise performance. In the meantime, this uncertainty and confusion has resulted in misinformation and varying trends around women’s sport performance in relation to their hormones.

How could it be that no unifying conclusions were found from all these studies? Well, that’s simple to answer, each woman is an individual.

Each individual woman’s female hormones will not necessarily fluctuate in a standard textbook way in terms of timing of hormone release or hormone concentrations. So, attempting to compare women in exactly identical points in the cycle is impossible.

This is precisely the conclusion that recent years of research have come to. The conflicting results were because the timing of hormone fluctuation was different in each woman, in each study.

Helping Women Perform Better In Sport

In order to address this gender data gap in sports performance, Forth conducted research with professional female athletes and gave the participants information that provided a greater understanding of how their unique cycles related to their performance.

woman doing long jump

This has led to the development of a unique and personalised Female Hormone Mapping product that maps the four main hormones – FSH, LH, oestrogen, and progesterone - for the whole of the menstrual cycle.  This data coupled with information on symptoms will enable a tailored report to be produced that offers personalised advice for that woman – treating her as an individual.

“Treat women as individuals and no statistics” as stated by the Vice President of the Royal College of Obstetrics and Gynaecologists (9)

Unlike other period tracking apps, Female Hormone Mapping does not use averages to predict a woman’s next period, instead it provides a personalised view of an individual woman’s hormones to predict her next menstrual cycle and overall hormone health.

Using this insight will ultimately enable women to achieve their full potential, in terms of sport performance as well as overall wellbeing, regardless of their age or chosen form of exercise.

In Conclusion

Many women are impacted by their menstrual cycle when it comes to exercise and sport performance, as well as general wellbeing.  We know this, the premenstrual symptoms women experience to varying degrees can have a big impact on everyday life, let alone exercise.

Some of the advice about doing certain types of exercise or eating certain foods are helpful for some women. However, it must be reinstated that this will entirely depend on your own, personal female hormone variations over a menstrual cycle and your personal biological response to these hormones.

Read Next: 'The Role Of Hormones In Women's Health'

View More Female Health Articles>>

Back To Blog >>

Female Hormone Mapping

This ground-breaking product maps how the 4 key female hormones fluctuate over your entire cycle rather than just a single day. Combining blood analysis with artificial intelligence and clinical expertise, our algorithm uses 8 lab results to plot how each of your hormones fluctuates throughout your cycle, totally unique to you. Giving you unparalleled insight into your menstrual cycle, whether you want to improve your wellbeing, optimise sports performance, are entering the perimenopause or are thinking about starting a family.
Subscription
Introductory Offer
SALE
Female Hormone Mapping
£129
£99
Combining blood analysis with AI and clinical expertise, our algorithm uses 8 lab results to plot how each of your hormones fluctuates throughout your cycle, totally unique to you

References

  1. Keay N, “Of Mice and Men” British Journal of Sports Medicine 2019
  2. Keay N, Lifestyle Choices for optimising health: exercise, nutrition, sleep British Journal of Sports Medicine 2017
  3. Bruinvels G, Burden R, Brown N, et al The prevalence and impact of heavy menstrual bleeding (menorrhagia) in elite and non-elite athletes PLoS ONE 2016;11:e0149881
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7381001/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6167362/
  6. Bruinvels G, Burden RJ, McGregor AJ et al Sport, exercise and the menstrual cycle: where is the research? British Journal of Sports Medicine 2017;51:487-488
  7. Costello JT, Bieuzen F, Bleakley CM Where are all the female participants in Sports and Exercise Medicine research? Eur J Sport Sci 2014;14:847–51
  8. Sheel AW Sex differences in the physiology of exercise: an integrative perspective. Exp Physiol 2016;101:211–2
  9. Rymer J, Brian, K, Regan L. HRT and breast cancer risk. BMJ Editorial 2019. dx.doi. org/10.1136/bmj.l5928
Dr Nicky Keay
Chief Medical Officer, BA, MA (Cantab), MB, BChir, MRCP.​
This article has been written by Forth's Chief Medical Officer, Dr Nicky Keay.
Nicky has extensive clinical and research experience in the fields of endocrinology and sport and exercise medicine. Nicky is a member of the Royal College of Physicians, Honorary Fellow in the Department of Sport and Exercise Sciences at Durham University and former Research Fellow at St. Thomas’ Hospital.

SHARE THIS ARTICLE​

Share on facebook
Share on twitter
Share on linkedin

Service Status

Kit Dispatch

Kits ordered before 1pm from Monday to Friday continue to be dispatched same day via First Class Royal Mail. After 1pm your kit will be dispatched the next working day. Orders placed on the weekend will be despatched Monday.

Postal Service

There may be some delays in parts of the UK occurring, we recommend posting into a priority post box. Click here for updates on the Royal Mail service. Click here for updates on the Royal Mail service.

Lab Analysis

Our labs are operating as normal.

Doctor/nurse reviews

Our doctors and nurses are currently working remotely and continue to review results.

Home phlebotomy appointments

Our home phlebotomy service is running but please be aware, if you or anyone in your household have experienced symptoms of COVID-19 within the last 14 days, due to the current government guidelines, we are unable to arrange an appointment at this time. Due to a high demand for nurses, along with current covid restrictions around the UK, there may be a delay in providing an appointment.

Customer service

Our customer service team are currently working from home, available to answer any questions via email.

Results dashboard

You can continue to access your results as normal either through your browser or via our iOS or Android app.

CORPORATE ENQUIRY

If you are an employer and would like to order multiple tests for your employees, please complete the form below.