Female Menstrual Cycle: Energy Needs Explained
The female menstrual cycle is a complex physiological process that affects numerous aspects of a woman’s body, including hormones, temperature, and metabolism. One phase of the menstrual cycle, known as the luteal phase, has been of interest to researchers studying Resting Metabolic Rate (RMR) and its fluctuations in women. In this blog post below, we explore the concept of resting metabolic rate (RMR) and how hormones affect a woman’s metabolic rate.
What is Resting Metabolic Rate (RMR)?
On the fourth page of your DEXA report, there is a section called Resting Metabolic Rate, or RMR. It refers to the number of calories you would need at rest, essentially before you go into a coma. It is the number of calories needed to maintain body temperature, heart rate and bodily processes.
Several factors can influence RMR such as genetics, muscle-to-fat ratio, physical activity, and hormones. Women in particular, experience hormonal fluctuations throughout their menstrual cycle that can affect RMR.
The 4 Phases of the Menstrual Cycle
The female menstrual cycle has four phases: The follicular phase, ovulation, the luteal phase, and the menstrual phase. These are primary regulated by what I like to call the yin and yang of hormones – estrogen and progesterone.
During the luteal phase, which is where most women experience pre menstrual syndrome (PMS) and more noticeable hormonal fluctuations, is where estrogen and progesterone start to rise and fall.
Resting Metabolic Rate in the Luteal Phase
Research shows that RMR during the luteal phase of the menstrual cycle, due to the thermogenic effect of progesterone. This is why women often find themselves hungrier and more ravenous before menstruation. Due to this rise in RMR, your caloric needs may rise by 100-300 calories.
It is believed that progesterone stimulates the sympathetic nervous system (SNS), leading to increased body temperature, which increases metabolic rate.
Practical considerations
Understanding the fluctuations of RMR during the menstrual cycle, particularly the luteal phase, can have detrimental consequences for women managing their weight, supporting their mood, reducing PMD and exercising effectively. Here are three practical takeaways:
1. Your energy and caloric needs fluctuate during the menstrual cycle. When you feel hungrier, lean into that, and listen to what your body needs. This will help you to reduce cravings, and support healthy mood balance and energy levels.
2. Nourish your body with balanced nutrition and complex carbohydrates like oats, rice, quinoa, barley, roasted sweet potato and pumpkin.
3. Track your menstrual cycle to understand where you are at any given time, so you can adjust your lifestyle accordingly to support your goals.
If you’re interested in understanding more about the menstrual cycle and what your caloric needs are to suit your goals, then book an appointment with our experienced Clinical Naturopath & Nutritionist Melissa, who can help guide you in the right direction.