How understanding your cycle can help you exercise smarter and live better

There is a lot of confusion around how we should train around our period, in part due to outdated misconceptions and in part due to the lack of research around the menstrual cycle. 

Historically, medical research has been conducted on men and extrapolated to women, leading to gaps in knowledge and misunderstandings about how women can and should exercise. New research is discovering the ways in which women’s hormonal changes affect our ability to do certain types of exercise, as well as the way our bodies respond to diet. 

I sat down with two experts on the topic - Dr Marcos Seijo, the programme leader for the sports science degree at the University of Greenwich, and Lily Gregory, who completed her dissertation around the menstrual cycle at the University of Greenwich - to discuss how we can better understand our bodies and its strengths.

What are the main misconceptions about women exercising around their cycle?

Women should avoid exercise during menstruation 

Dr Seijo said that while some people feel fatigued or cramps on their period, others perform well at moderate or even high intensity at this time. 

Studies show exercise can help with cramps as it promotes blood flow and the release of endorphins, which act as a natural painkiller.  

The cycle doesn’t impact performance 

In most people, it does. This shouldn’t be viewed as a negative thing; however, it simply means there are better times to focus on certain types of exercise. The hormonal changes throughout our cycle impact our strengths, both physical and mental.

Training plans should be the same throughout the whole month 

As discussed above, due to hormonal changes, many people benefit from changing up activities. Attention to times we may be more prone to injury and adjusting accordingly can also be beneficial. 

Birth control removes the hormonal fluctuations entirely 

Hormonal birth control will mitigate or alter the fluctuation of hormones but will not remove them, and consequently the effects of hormones will still impact performance. 

Everybody experiences the same symptoms during the cycles 

Lily insisted that each individual will experience hormonal changes and the effects differently, so try our recommendations but ultimately find a routine that works best for you. 

There are good and bad phases of the cycle 

There is a lot of negativity around the luteal phase, not helped by recent social media trends. Lily warned of a placebo effect that can take place if you give in to these ideas, as our bodies respond to our minds' preconceived pessimism.

How to adapt training and diet to make the most of our training

According to the NHS, a “normal” menstrual cycle lasts between 21-35 days. Here we look at the days of the cycle based on an average of 28 days. 

When it comes to changing our training around our cycle, Dr Seijo said: “we can adapt the volume and intensity of the type of exercise according to the configuration of the hormones, focussing on different characteristics or impacts on energy, recovery, strengths, endurance and motivation.”

Menstruation: Days 1-7

When we start bleeding, oestrogen and progesterone are low, so some women may want to moderate the intensity and volume, using this phase as restorative training. This can be in the form of yoga, bodyweight exercises or swimming. 

Dr Seijo said, “It is very important that women focus on the nutrition during this phase and take in more iron due to the risk of iron anaemia [iron is a main component of red blood cells, and blood loss during menstruation can lead to iron deficiency] then listen to the body and hydrate.”

For iron he recommended eating meat (particularly red meat), lentils, spinach, pumpkin seeds and fortified cereal. But, as not all the iron we eat is absorbed, they both recommended eating vitamin C to increase iron absorption. 

Dr Seijo also advised eating anti-inflammatory foods to reduce cramps and fatigue. Salmon, turmeric, ginger and berries are all good sources of antioxidants that help with inflammation. 

To combat the irritability that we may feel on our period they both recommended complex carbohydrates such as sweet potato, oats and quinoa. These carbs can help balance our blood sugar levels, avoiding the sharp crashes we might have from eating simple carbohydrates such as white bread or white rice that make us grouchy. 

Follicular phase: Days 7-12

A couple of days after we start our period, oestrogen increases, increasing energy in the body and brain. This time is optimal for working on strength, power and technique. If there’s a squat PB you’re going for or a tough HIIT class you’d like to do, the follicular phase is a great time to give it a go. 

We also have better focus during this time, so will perform well in skill based sports. 

During the follicular phase we have higher insulin sensitivity, meaning we burn carbs more effectively for fuel. 

If you are upping the intensity of your training during this time, ensure you are also taking in enough protein and B vitamins. The protein will help with muscle repair and growth as well as energy, and a healthy amount of vitamin B1, B6, B9 and B12 will improve both the amount and quality of red blood cells to transport oxygen around the body.

Ovulation: Days 12-15

While we are ovulating oestrogen is at its peak, as is testosterone, so most women will find they have higher energy. Dr Seijo says this could be the best time for competitions - but to be careful; there is a higher risk of injuries in this phase.

Dr Seijo said, “This happens [injuries] mainly during the ovulatory phase because this peak in oestrogen will increase the ligament laxity and will reduce the stiffness and the structural integrity of the ligament. Consequently, the joint will suffer much more because of an increase in joint mobility and a reduction in neuromuscular control.”

Zinc and magnesium are important in this phase to support our hormonal balance, which we can get from dark chocolate and chickpeas. Anti-inflammatory foods are also great here to fight against the inflammation and stress produced from the intensity or volume of training sessions. 

Luteal phase: Days 15-28

In the time between ovulation and our next period starting, oestrogen drops and progesterone surges, making us better suited to low-intensity, long duration exercise such as gentle long runs or cycles, or lower weight, higher rep strength workouts. This may be a good week to work on endurance or do some active recovery. 

Our insulin sensitivity decreases during the luteal phase and our bodies become better at burning fat for fuel. This may be why we crave fatty foods just before our periods, specifically when we start to get pre-menstrual symptoms. But it’s important that we stick to healthy fats; avocados, olive oil, full fat yoghurt and salmon are all good options. Good quality fats will also help improve brain function in a time we might be prone to reduced focus and cognition.

Body temperature changes

Our body temperature changes throughout our cycle, which results in changes in appetite, vulnerability to dehydration and how much we need to warm up or cool down for exercise. For example, higher body temperatures during ovulation and the luteal phase mean we are more vulnerable to dehydration in these periods.

Lily discussed the importance of other factors around exercise. She said, “If you're not going to change your exercise around your cycle, fine, but then you need to change your recovery strategies around your cycle because they are going to differ at different points. During the follicular phase, you should spend more time warming up, for example, because your body isn't naturally as warm. Then during the ovulatory or luteal phase, you should spend more time cooling down because you're going to be warmer.” 

Despite great advances in research, not all women have regular periods.

I spoke to Lily Wilkinson, an outdoor educator and recreational endurance athlete from Sydney, about her experiences with Polycystic Ovary Syndrome (PCOS), a common disorder in women that can affect ovulation, leading to irregular periods.

After suffering from bad cramps for years, she found a doctor that helped her with a “PCOS friendly diet”, focusing on whole, unprocessed foods and eating low-glycemic index food – swapping white bread for wholegrain bread and adding healthy fats. Since changing her diet, she has found she has far more energy to do physical activity around her period.

She gave her advice for when our bodies aren't performing to the level we want them to: "I allow myself to get frustrated, then I reflect on it later. I say: look, that's life and you did amazing for what you were able to achieve. Trying and having a go is already an amazing achievement."