Exercising and menstruation cycles
Tailoring exercise routines around your period: evidence-based or Instagram-craze?
By Jessica Taylor
In this blog, Jessica Taylor, who has a master's in public health, explains what happens to the body during the menstrual cycle and why (and how) some people are adapting their exercise around those hormone changes.
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People with active lifestyles are increasingly using data and apps to track and monitor exercise and lifestyle metrics such as calories, heart rate, sleep and more. As apps for tracking individual’s periods grow in popularity, so does the trend for scheduling exercise routines around the menstrual cycle. However, what are the proposed benefits to this, and is there evidence to back up this approach?
Firstly, let’s look at what happens to the body during the menstrual cycle. The menstrual cycle is the time from the start of one period to the start of the next period. The ‘textbook’ length is 28 days, but it can last anywhere between 21 and 35 days. Oestrogen and progesterone are key hormones throughout the cycle, as fluctuations in their levels trigger ovulation and the period to begin. The cycle can be split into four distinct phases:
The early follicular phase: At the start of the follicular phase the uterus shreds i.e. your period happens. Hormones are low and steady during this time
The late follicular phase: This phase starts when the period ends, and oestrogen beings to rapidly increase. It peaks at ovulation.
The early luteal phase: Ovulation marks the start of the luteal phase. For the next 7 days oestrogen and progesterone begin to increase and peak.
The late luteal phase: Following this, the body enters the late luteal phase if the egg is not fertilised. Oestrogen and progesterone levels fall, which prompts the body to shred the uterus lining, thus triggering the next period and the start of a new cycle
So, why are people adapting their exercise around these hormone changes? Whilst these hormone changes are primarily driving the menstrual cycle, we have hormone receptors for oestrogen and progesterone throughout the body, meaning these hormones can influence other systems such as the cardiovascular system and muscle system. Therefore they could impact exercise performance and recovery.
It is claimed that high intensity exercise should be avoided during the luteal phase. This is due to high oestrogen and progesterone levels resulting in possibly increased body temperature, increased resting heart rate and increased tissue breakdown. Some research may support this, such as this study with 12 participants finding performance was negatively impacted during the mid-luteal phase, and this study finding that the mid-luteal phase could potentially impact prolonged endurance exercise.
A Systematic review, which looked at over 50 studies and as such is considered much more robust evidence, shows that exercise performance may actually be impacted during the early follicular phase. However, the researchers also acknowledged that the impact was “trivial” and that the quality of the studies examined was generally low, and so advise these results should be interpreted with caution. Furthermore, studies have shown risk of knee injury may be higher during the late follicular phase when oestrogen is rising. However, expert’s advice is not to avoid exercise during this phase, but instead to pay particular attention to warming up and recovering effectively. It also needs to be acknowledged there is a distinct lack of research in general regarding women and exercise; in over 5000 studies in sport and exercise research, only 34% of participants were women, and only 6% of studies looked solely at female physiology.
So, should exercise programmes be adapted across the menstrual cycle? Well, the answer depends on the individual.
Firstly, the evidence examined looks at results from large groups of women and identifies trends. However many individuals may not have ‘textbook’ menstrual cycles or hormone levels, and so should be cautious about applying broad stroke approaches to individual exercise regimes. England Institute of Sport have recognised this, and are measuring individual athletes oestrogen and progesterone levels to determine if this impacts performance on an individual level instead of applying training schedules to all athletes based on generic menstrual cycle phases.
Secondly, every person’s menstrual cycle is different and experiences of things like pre-menstrual symptoms and period cramps vary massively. If you personally recognise changes to your energy levels and ability to recover from exercise during particular parts of your menstrual cycle, by all means go ahead and tailor your individual exercise regime around what works best for you and your body.
Lastly, on average women exercise less than men, and are less likely to meet the recommended guidelines of 150 minutes of moderate intensity exercise per week. More needs to be done to make regular exercise accessible and attractive to women so they are not missing out on the huge health promoting benefits it has. The focus really should be on how exercise can become a consistent part of the lifestyles of women, instead of giving ‘one size fits all’ advice on why women and people who menstruate should potentially limit their physical activity during certain periods of the month.
ABOUT JESSICA TAYLOR:
Jessica Taylor
Jessica works within public health, and has a master's in public health from the University of Manchester. She is interested in the impacts of the wider determinants of health throughout society, and the ways non-medical interventions can promote the physical and mental wellbeing of people. As a keen long-distance runner, Jessica also has particular interests in nutrition and gut health, exercise physiology and promoting a body-neutral, holistic approach to wellbeing.
Connect with Jessica on Instagram here.