"There are more things female runners worry about than male runners. Having menstruation or period on race day, is one of our greatest nightmare! Our period comes once a month, so it is vital for women to understand how menstruation affects our running at different stage of a menstruation cycle. What are the things we should do/eat or avoid. I would like to share my findings in the page, specially dedicated to female only."
What is menstruation?
Menstruation, also referred to as a "period". Regular menstruation lasts 2-7 days within a cycle that ranges from 21-35 days. When bleeding occurs between periods, or is longer or heavier than usual, this is called abnormal or irregular bleeding. Menstruation is a hormonal process that includes an egg and uterine lining flowing out of the body.
What are the menstrual stages for runners?
Women should be aware of their monthly cycles and plan their workouts accordingly. Every woman is different, but menstrual cycles are all similar and can affect your running. The levels of estrogen and progesterone change continuously throughout the cycle as a complex interaction of positive and negative feedback mechanisms regulate the timing and amount of hormones that are secreted. With the large fluctuations in the concentrations of these hormones, the phase of the menstrual cycle significantly affects a female runner's hormonal environment, therefore, her physiology.
1. Follicular Phase - Begins from the first day of period which lasts for about 11-21 days (typically lasts 14 days). Estrogen rises gradually and peaks on day 14, right before ovulation. The burst of estrogen toward the end of the follicular phase causes a surge in luteinizing hormone on day 15 to initiate ovulation. During the follicular phase, the progesterone level remains low.
2. Luteal Phase - Usually lasts 14 days, where progesterone rises. Estrogen drops after ovulation before rising again toward the middle of the phase. The increase in progesterone causes body temperature to increase in preparation for the fertilization of an egg. If fertilization does not occur, both estrogen and progesterone level decrease abruptly. The luteal phase ends when period comes.
Physiological effects and performance implications
While a man's hormonal environment is pretty stable, a woman's is constantly changing. Any physiological changes resulting from menstrual cycle-induced fluctuations in estrogen and progesterone are exacerbated during exercise, especially if it is intense. When you go for a hard run, the concentrations of estrogen and progesterone in your blood increase during both the follicular and luteal phases. Low-intensity exercise, however, does not alter the concentrations of these hormones.
If you bleed a lot during menstruation, it is possible that your blood's hemoglobin concentration may decrease, which can negatively impact your ability to transport oxygen in your blood. Since iron is an important component of hemoglobin, iron loss often accompanies a lot of bleeding. If this happens, you may need to supplement your normal diet with iron.
Many female runners exhibit atheletic anemia (low blood iron levels due to physical activity), especially if they lose a lot of blood during menstruation. Athletic anemia is very common among female runners, especially those training at altitude.
Body temperature
Body temperature changes rhythmically throughout the menstrual cycle, peaking during the luteal phase in response to the surge in progesterone. Progesterone acts on the brain's hypothalamus (the temperature control center), which increases the set-point temperature. A higher body temperature increases the threshold for dissipation of heat. In other words, a woman's body must reach a higher temperature before her thermostat compensates and begins to cool itself.
That's not a good thing when you are running on a hot and humid day, as you want to begin the cooling response as soon as you can. Estrogen has the opposite effect on the hypothalamus, decreasing body temperature, which explains why body temperature is lower during the estrogen-dominant follicular phase.
The increased body temperature during the luteal phase remains elevated during exercise and when exercising in the hear. A higher body temperature during the luteal phase makes it harder to run in the hear during this time, as you do not begin sweating to dissipate heat until you have reached a higher body temperature.
You also have a decreased ability to dilate the small blood vessels under the skin, which compromises your ability to release heat to the environment. Hyperthermia (an increased body temperature) is one of the factors that cause fatigue during prolonged exercise. Thus, long, intense workouts and races in the hear can be more difficult during the luteal phase of the menstrual cycle. The increased body temperature during this phase can also put you at an increased rish of developing heat-related issues such as heat exhaustion and heat stroke. Training improves your ability to regulate body temperature.
Source from - Competitor
