Training and racing with the menstrual cycle – 14 months of learning
It has been one year and two months since I stopped taking the combined pill, a tablet I had been taking daily for over 10 years. For the first time I was trying to fit in training and racing with my menstrual cycle. It has been wild. Fourteen months later I think I have finally worked out how to work with my female biology for optimal performance. In this blog post I detail the lessons I have learned – hopefully they will be helpful to other females and also to men who want to understand what it feels like to be a female athlete. This is a topic that I really don’t think there is enough discussion about. First off, a quick biology lesson.
Quick biology lesson
Prior to giving up the pill I had very little knowledge of how hormonal variations during the menstrual cycle effect athletic performance. I also had no knowledge about how taking the pill was negatively effecting my athletic performance – but that’s another story. Oestrogen and progesterone levels in women change dramatically throughout each cycle, effecting a women’s core body temperature, heart rate, respiratory rate, and blood plasma volume. While menstrual cycle length varies greatly from woman to woman, the average cycle is 28 to 32 days in duration and consists of the follicular phase (days 1-14) and luteal phase (days 15-28), with day 1 being the day menstruation begins.
In the follicular phase oestrogen and progesterone levels are low. Women are primed for peak performances during this time. Yes, even while having a period, hormones are primed for performance. It is uncomfortable training with your period because of the localised inflammation in the uterus area (making you also feel like you need to constantly stop for the toilet), but this discomfort is nothing compared to performance impediments if you race on days 25-32 (though some women have terrible period pain which is far beyond the mild discomfort I feel). I am always so excited if I get my period right before racing because it means I have avoided racing on days 25-32, that I am healthy, and that I am primed to have a peak performance.
During days 25-32, the high oestrogen and progesterone levels reached in the mid luteal phase drop dramatically. The sudden drop in estrogen and progesterone causes:
1. A higher core body temperature – making it more difficult to perform in hot conditions, and making thermoregulation generally more difficult.
2. Blood plasma levels drop to up to 8% lower than normal levels.
3. Respiratory rate increases.
4. Heart rate increases. For me this can be up to 10bpm for resting HR and this generally translates into all heart rate zones – meaning my heart rate is significantly higher at any effort level – it is super tough racing above aerobic effort on days 25-32.
5. Low glycogen availability – glycogen stores are not readily available, meaning the body relies on blood sugar levels and sugars ingested while exercising to fuel efforts.
6. More fat burned as a fuel source. This is not optimal for race performances which are high heart rate, but could be ok if you are doing a long and very slow training run where fat is burned as a preferred fuel source.
7. More muscle is catabolised as a fuel source, making the ingestion of protein very important after training during the luteal phase.
8. Lower levels of co-ordination. This is relevant for technical running/fast descending/competing in obstacle races, and is less relevant for running on smooth surfaces.
9. Difficulty recovering generally and especially after hard and race efforts.
10. Water retention leads to bloating/puffy limbs, which in my experience makes running feel slightly different.
For me personally, my heart rate and breathing rate during days 25-32 make running feel the same as it does at 3,000m above sea level. In particular, I really notice the high heart rate, mainly when training or trying to fall asleep. I also really notice how difficult it is to race or to do high intensity training and how recovery is much slower. Despite these difficulties, it is possible to achieve a solid (maybe not peak) performance during days 25-32.
Lessons learned
Training
Over the past 14 months how I respond to and feel about training during the menstrual cycle has followed this pattern:
1. Days 1-14 I can crush both strength training and running training. I can also recover quickly. If I feel like doing extra training or feel like pushing harder in a run than programmed I will do so. I try and take advantage of low oestrogen and progesterone levels to get quantity of training in here. I was completely missing out on this phase when I was taking the pill, and wow was I missing out.
2. Days 15-24 normal training. No longer have super human powers, but can train normally and recover normally.
3. Days 25-32 relatively normal training but I may modify sessions on the day to remove hard efforts, or deload. If a session is average I understand why and I do not feel bad about it.
You will hear a lot of people advocating for a rest week from day 25 of the menstrual cycle. Make sure you do what suits you. As an athlete I cannot justify having 7-10 days off from training a month. I find that a better option than completely writing off training is to focus on recovery and nutrition during this time. From day 25 onwards I try and get an hour of extra sleep a day and spend twice as much time on foam rolling and stretching. I take magnesium, zinc and fish oil supplements each night to assist with general inflammation and recovery (on advice from an accredited sports dietician).
I also slightly adapt my eating habits. In the follicular phase the body burns more carbohydrates, so I eat my usual high carbohydrate diet during this time. In the luteal phase, and particularly from day 20 onwards, the body burns more fat because it cannot access stored glycogen as well. The body also has a higher calorific need during this time, which can lead to the body burning muscle for fuel. There are a few ways I adapt nutrition from day 25:
1. Having protein immediately after all exercise to help minimise muscle loss and start the recovery process.
2. Having carbohydrate immediately before all exercise to boost blood glucose levels. The body cannot readily use stored glycogen and so having accessible glucose in the blood is important, as is intra exercise fuelling (for efforts more than 90 minutes).
3. Focusing more on eating quality fats and protein.
I also want to highlight how important it is for women to consider training by heart rate so that during the luteal phase they can see how hard their body has worked in a session and adjust accordingly. Most trail runners and OCR athletes would already be training by heart rate, as pacing is not a good guide to go by when courses have any kind of vertical gain or technicality. However, if you are a woman who is really attached to running by pace, I recommend switching to heart rate for the luteal phase or at least paying attention to heart rate data. A reminder that heart rate should be measured with an arm or chest strap, as watch measured HR can be 10-15bpm off, and even when worn very tightly on the skin, pigmentation and hair can cause inaccuracies.
Racing
Races happen when they are scheduled and that might not be an optimal time in the menstrual cycle. My experience is that racing on days 1-14 I feel insanely awesome. Days 14-23 are good days to race. Day 26 onwards it is really difficult to perform to potential.
I have had some races where I have felt insanely awesome because they have been during the follicular phase of my menstrual cycle. In 2021 these races have included Kowen trails (2nd, day 10), Mt Buller Skyrun (1st, day 11), and Port Stephens Spartan (3rd, day 13). I also had a great race at Australian Alpine Ascent on day 20 of my cycle at attitude. The two times this year I have underperformed both occurred late in the luteal phase, and this is probably no coincidence. For example, Ultra-Trail Australia was on day 26 of my cycle, my heart rate and respiratory rates were high (as per normal at that time of the menstrual cycle). If you are racing in the luteal phase of your cycle you really need to bring your best mental game with you to maintain effort despite the higher heart rate, respiratory rate, and core body temperature. I did not have my best mental game with me at UTA. Although I finished 8th female which is not a bad result in the second largest trail running event in the world, I definitely underperformed. This is not the first time I have had to race on days 25-32. In 2020 I had a string of three races in a row that occurred on days 26-32. This weekend I have the Kowen winter half marathon which is due to fall on day 32 of my cycle (probably the worst possible day for performance). So it is a learning process and each day I have a long run or race day on days 26-32 I try and get that little bit better at applying what I have learned.
What I have learned about racing on days 26-32:
1. Intra racing fuelling is very important. The body cannot readily access stored glycogen, which means it relies more heavily on blood glucose and fat. In fast races, your body’s preferred fuel source is carbohydrate, and so you must ensure that you are fuelling early and frequently. I traditionally have trouble with intra race fuelling. It took me two years to just learn to stomach a gel while racing. I have improved dramatically since then but I tend to err on the side of under fuelling for long runs and racing. This is not an option if you want to perform well in the luteal phase, and early and consistent fuelling is something I will be practising. For longer races, racing in the luteal phase is less of an issue in terms of fuelling because you are running predominantly in your aerobic zone, and will be burning more fat as fuel.
2. Mental game must be strong. With a high heart rate, high respiratory rate, and reduced blood plasma volume, it is physically more difficult to perform at the same level. So you must be prepared to work harder than normal race effort to achieve the same result. It’s tough, but if you don’t go in psychologically prepared, you will not be able to maintain the necessary race effort, leading to underperformance.
3. Shakeout run will feel terrible. I now use the shakeout run during luteal phase to try and ‘get used to’ that feeling of a high heart rate while running. The race itself, after the first 20minutes of adjusting to the high heart rate and respiratory rate, rarely feels as difficult as the shakeout run, so I also keep that in mind.
4. Get more sleep and focus on nutrition as set out in the section on training.
By far the most important thing I have learned is to listen to my body. It has been a year long journey of tuning in to my body. I do not think it is a coincidence that I have had a six month injury free streak. If you haven’t thought about optimising your performance around your menstrual cycle, I really recommend that you keep a diary for a few months recording how you feel and how the time of the month may be effecting your performance.