For female athletes and highly active women, irregular periods can be a common and concerning issue.
Whether you’re a dancer, runner, climber, or dedicated gym-goer, the challenges of maintaining peak performance and doing what you love, while also managing your menstrual cycle can be daunting. Many of my clients approach me with concerns such as future fertility (will I be able to conceive?!) and confusion (my cycles were completely regular until 6 months ago!). Understanding why these irregularities occur is crucial for both maintaining your health and optimising your athletic performance. For you, it may be a combination of all the following reasons, or one more specifically. To go deeper with this investigation, know that the fertility awareness method can help you monitor your hormones to gain a deeper understanding of the root cause of your personal irregular periods.
The Impact of Physical Stress on the Menstrual Cycle
One of the primary reasons highly active women experience irregular periods is due to the physical stress their bodies undergo. Exercise is a form of stress, and when performed at high intensities or volumes, it can significantly impact the hormonal balance that regulates the menstrual cycle.
When the body is under significant physical stress, it may perceive it as a threat to survival. Think of it like this: you may be choosing to put your body under intense pressure, but the ‘old’ part of our brain cannot differentiate between this, and threats such as running from tigers or climbing trees to escape from bears. This can trigger a survival mechanism where the body prioritises essential functions, like maintaining energy for muscle repair and immune function, over reproductive functions. As a result, the body may reduce the production of reproductive hormones like estrogen and progesterone, leading to irregular periods, missed cycles, or even amenorrhea (the absence of menstruation) and other cycle symptoms.
Energy Availability and Menstrual Health
Another critical factor is energy availability, which refers to the amount of energy left for the body’s physiological functions after accounting for the energy expended during exercise. Female athletes who do not consume enough calories to meet the demands of their training are at risk of low energy availability (LEA). This condition is often part of a broader spectrum known as Relative Energy Deficiency in Sport (RED-S).
Low energy availability can disrupt the hypothalamic-pituitary-ovarian (HPO) axis, the hormonal system that governs the menstrual cycle. When the body doesn’t receive sufficient energy, it can reduce the production of gonadotropin-releasing hormone (GnRH), which in turn affects the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones are crucial for ovulation and maintaining a regular menstrual cycle. Without them, menstrual cycles can become irregular or stop altogether.
Body Fat Percentage and Hormonal Balance
Body composition, particularly body fat percentage, plays a significant role in menstrual health. Estrogen, a key hormone in the menstrual cycle, is partially produced by fat cells. Female athletes, especially those in sports that emphasise leanness, may have lower body fat percentages, which can lead to lower estrogen levels. Insufficient estrogen can result in irregular periods or amenorrhea.
Creating a baby (gestation) is a period of intense drain on energy and fat stores. Rapid fetal brain development requires high levels of cholesterol to meet the needs of this fast growth, in this very crucial stage of the baby’s neuroplasticity development. Our intelligent bodies know not to prepare for reproduction when these stores are low!
It’s essential for active women to find a balance between achieving their performance goals and maintaining enough body fat to support their menstrual health. Striking this balance can be challenging, but it’s necessary to prevent long-term health consequences such as bone density loss, cardiovascular issues, mental health and fertility challenges.
As performance nutrition consultant for the Golden State Warriors Dr Dana Lis says ‘female athletes don’t win first place when their menstrual cycle is missing.’ That sounds like motivation to me!
Psychological Stress and Menstrual Irregularities
Beyond physical stress, psychological stress can also contribute to menstrual irregularities. The pressure to perform, meet expectations, and cope with the demands of intense training schedules can create significant mental strain. The building blocks of estrogen and progesterone are made from the same materials as cortisol, a hormone which is released during times of stress, to aid us in survival. For this reason cortisol will always be prioritised over our sex hormones. Chronic stress can elevate cortisol levels, which when persistently high, can interfere with the normal functioning of the HPO axis, leading to menstrual irregularities.
Conclusion: Prioritising Holistic Health
For female athletes and highly active women, irregular periods are not just an inconvenience; they are a sign that the body is under strain. Whilst manageable in the short term, long term your capability and performance will be impacted, as well as your overall well-being. Addressing this issue requires a holistic approach that includes proper nutrition, stress management, and a balanced training regimen. By understanding the root causes of menstrual irregularities, you can take proactive steps to support both your athletic performance and your overall well-being.
Remember, your menstrual cycle is a vital sign of your health. Prioritising your cycle health is not only essential for your reproductive well-being but also for sustaining long-term athletic success.
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