Do you ever notice that some weeks you feel like Wonder Woman, others you feel like a 15-year-old tabby cat? Have you ever thought about tracking when these feelings occur? Have you ever thought that this rollercoaster of feeling may be linked to your monthly cycle? Let’s explain the physiology behind the menstrual cycle, how this may make you feel, and how we can use this to our advantage.
A quick bit of physiology (don’t sigh, it’s important): The menstrual cycle is divided into the follicular phase (days 1-14) and the luteal phase (days 15-28). Day 1 of the follicular phase is the beginning of the bleeding when the uterus lining sheds, the length of which will vary from person to person but is usually 4-8 days. Post-bleeding, while Follicular Stimulating Hormone (FSH) is preparing the dominant follicle (follicles produce eggs) for egg release, oestrogen produced by this follicle progressively increases (rebuilding the endometrial lining just shed) and peaks around days 13-14. This stimulates a rapid increase in Luteinising Hormone (LH). This spike in LH results in the release of the egg in preparation for fertilisation. The empty follicle transforms into a corpus luteum (like a shell), which begins to produce progesterone as well as oestrogen, peaking in the last quarter of the menstrual cycle. If the egg is fertilised, progesterone continues to be released and supports the pregnancy. If not, the corpus luteum breaks down and oestrogen and progesterone decline, allowing the cycle to start again.
So, onto the bit you’re more interested in, what does this mean for your training? Let’s look at the phases in turn, assuming a 28 day cycle. The follicular phase is Wonder Woman time! The first part of the follicular phase, days 3-10, is when the worst of the period has subsided (hopefully around day 3 of bleeding) and oestrogen is slowly rising. The latter half, days 11-16, is where the spike in testosterone and peak in oestrogen seen around ovulation. During these phases, especially the second half, is the time where you will feel your strongest and most energetic. Elevated oestrogen has a positive role in training resulting in you taking longer to fatigue, recover from muscle damage more rapidly, have a lower pain threshold, and utilise carbohydrates better (increased insulin sensitivity). Testosterone increases energy, strength, lean mass, confidence and fat burning potential. This is the ideal time to push the weight, shift training to push the volume and incorporate higher intensity techniques such as HIIT, as well as proportioning more of your caloric allowance towards carbohydrates. You are most set to succeed in week two, so go for those PBs! In this phase you may also find your appetite is reduced. The opposite is seen in the luteal phase following so you may want to lower calories here in preparation to increase them in the later weeks if you are dieting.
Now onto the old cat feels, luteal phase. At the beginning, days 17-25, while not as high as in the follicular phase, oestrogen is still sufficiently high to support moderate intensities and volume, However progesterone begins to climb rapidly, increasing cravings, decreasing insulin sensitivity and core body temperature. During this phase it is wise to position your training somewhere in between – focusing on moderate weights, technique and mobility. Nutritionally, it can be a wise strategy for some to reduce carbohydrate intake and prioritise protein and fat intake, which will mitigate the risk of excessive fat storage, while controlling cravings and hunger by keeping you more satiated with slower digesting foods. If you chose to reduce calories in the earlier weeks, now is the time to bump them up. Bear in mind that your basal metabolic rate will only increase by around 10-15% (200kcal) during this time so there’s not need to eat for England! Unless you aren’t dieting and want to of course! Going into the last week, days 26-2, just before and during heavier bleeding, depleted testosterone and oestrogen, bloating, discomfort and elevated body temperature are hefty barriers for many. Hello PMS. For many female athletes, this means difficulty maintaining heavy strength or hypertrophy work. It is therefore wiser for those to treat this phase as a "Reset" phase, where loads are lightened and movements involving complex coordination or that rely heavily on core stability should be lessened. Some find it helpful to use this as an opportunity for swapping resistance training for low intensity activities like walking, swimming, yoga, Pilates etc. or even complete rest. The raised BMR applies here too so be kind to yourself and recognise your hunger. Hopefully this may help you understand the feels and the next time you feel like you need to go to the vets to be put down, you may just remember why, and forgive your body for what is actually an incredible process and the reason we are all here!
William Meddick-Dyson FdSc BSc MSc and Dr Stephanie Hill BSc MBBS
