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Ask Stacy: How Can Tracking Your Period Help Your Training?

Tracking your training with your menstrual cycle can have a huge impact on performance.

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Whether you call it your monthly visitor, your period, or one of many other creative euphemisms, menstruation is a mainstay in most women’s lives from early adolescence until menopause (late 40s/early 50s). Because of the routine nature of this biological process, it’s easy to become complacent or to ignore tracking it. Keeping track of your period is important for a number of reasons, primarily health-related, but recently we have seen an increasing amount of discussion around training and racing in relation to your cycle. Knowing how your cycle affects your physical symptoms, moods, training readiness and recovery, gives you vital intel on your individual cycle, which is a big powerhouse in dialing in training adaptations and performance. Thanks to technology, it’s now easier than ever to keep track.

Before we dive in, let’s go through a few things, because just noting down the first day of bleeding to the next day of bleeding is not exactly what we mean by “tracking your menstrual cycle,” (although this is a great start to ensure you are in a positive energy state, e.g. not experiencing low energy availability, LEA). In short, what you want to understand is how the fluctuations of your hormones can affect you.

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There are two layers to understand when we are talking about the menstrual cycle and training or performance. First, despite what some women might think or feel, there really is no negative point at any time in the menstrual cycle for performance (and this has been backed up in recent research and systematic reviews). However (and it can be a big however), for some women, the psychological components can supersede the physiological, e.g. they’ve had a negative training or racing experience while on their period and there’s subsequently a lot of negative self-talk. But, that aside, when we discuss tracking the menstrual cycle to use our physiology to garner higher quality training sessions (and therefore better adaptations), it is really important to remember that we can use this information (our hormone profile) to enhance our training loads due to different resilience to stress across the menstrual cycle.

The second layer is what I’ll call the psycho-sociological layer. This represents the perceptions and the environment of the woman (culturally how the menstrual cycle and her period is perceived and/or how she feels about having her period), and the lived experience of her cycle, e.g. if someone experiences heavy menstrual bleeding (HMB) and thinks this is normal, then she will not be able to train or perform well during the menses phase. More than 35% of recreational female athletes experience HMB, but we don’t talk about what is a normal bleed, so it is often missed. By tracking and understanding the nuances of her lived experience, this can empower and remove the negative self-talk that women often have in certain points of their cycle.

RELATED: Period Tracking for Female Athletes

Tracking Training According to Hormone Changes

When it comes to training, we all (regardless of gender!) should look to train smarter, not harder. For women who are menstruating, this means training according to hormone fluctuations (train better, not more!).

Physiologically, when the hormones drop in the day or two before bleeding, there are systemic changes that occur to enhance our body’s ability to take on stress. Our immune system responses change, from being suppressed after ovulation to being more resilient, and there is a drop in inflammation after the first two to three days of menses. Our core temperature drops back to a lower baseline, we can access carbohydrate from the muscle and liver due to the low levels of estrogen and progesterone, our heart rate variability (HRV) is higher (the elevated progesterone increases sympathetic drive), our respiratory rates are lower, and our resting heart rates are lower. Together, all of this allows our bodies to have a bigger range from low- to top-end and recover well. But the caveat here is that if, during the first one to two days of menses, there is a lot of cramping and pain, then a woman will be less willing to hit their training sessions hard, although short, sharp intensity (a few 20 to 30-second bursts) can increase growth hormone and decrease inflammation which helps with these symptoms.

The Impact of Birth Control

I am often asked the question, “But what about birth control? How does this change things?” Well, it’s a good question. Yes, you can still track your symptoms and motivation, but it is a completely different kettle of fish. Using oral contraceptives (OCs) completely downregulates your natural hormones. In the first five or so days of the active pills, as the hormones start to accumulate in the system and baseline levels elevate, a woman is similar to a naturally-cycling woman in the low hormone phase (ready to hit it hard and recover well!), but by day six or seven of the active pills, we start to see a change in stress resilience: it takes more load to get the same adaptations and also an increase in recovery needs. This continues through the active pills and until day two of the placebo/sugar pill, into the withdrawal bleed (not a true period, but a bleeding from the hormone level dropping from the inactive pills). During this time through to day five of the next week of active pills, a woman on OC is primed to hit it hard and recover (primarily because there are very low levels of exogenous hormones, and natural hormones are still signaled to downregulate because of the residual exogenous hormones). In short, the second day of the withdrawal bleed through the first week of the active pills is a great time to set PRs! So, the idea on using the OC to manipulate not having your period is not necessarily to your advantage. Also note that combined OCs increase oxidation and inflammation, both of which impede adaptations and fitness gains.

What to Track: Menstruation Data to Monitor

At the bare minimum, you should keep track of the first day of your period each month. This information is enough to help you notice most irregularities. However, you can get pretty sophisticated with your period tracking. Keeping the details outlined below helps you monitor your training and health more closely. It can also help you prepare yourself for other symptoms related to menstruation.

Here are some points you should consider tracking:

  • Period heaviness by day
  • Does your period start with a couple of days of heavy flow and then taper off to a day or two of spotting? If so, you probably require different strengths of pads or tampons through the course of your cycle. Anticipating these needs can make your life much easier
  • Changes in mood during the menstrual cycle
  • If you experience PMS or PMDD, your moods may seem subject to random fluctuations. By tracking your moods in the days leading up to and during your period, you just might find that you wake up on the wrong side of bed exactly two days before starting your cycle each month. Forewarned is forearmed, so the more you know about what to expect from your moods, the better you can cope with them as they come
  • Energy level, appetite, and other changes


Triathletes are typically very good at monitoring and tracking their training and performance patterns. For menstruating women, this is arguably the most important information you can track. Tracking your energy levels and motivation can help you dial in hard days and anticipate when you’re going to need recovery days. For example, if you find you are always exhausted on day 23, or that you get a headache before your period starts each month, you have this information and can relay it back to your coach. Modifying your training to match your energy and motivation can significantly improve the days of hard workouts, and, in turn, your training load, adaptations, and performance. When you track every aspect of your cycle, you won’t be blindsided by your body’s reactions to menstruation. Everybody wins. Period.

RELATED: How to Manage Your Period on Race Day

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