A physically active female knows when her menstrual cycle is about to begin, without even counting the days. In the 5-10 days before it starts, a woman’s body is priming for major physiological changes that makes her unique from a man. This premenstrual time requires special nutritional and recovery considerations when a woman is exercising, and in particular, if she is in competition. 

The Typical Menstrual Cycle Progression

Menses is the beginning of the 28-day menstrual cycle and is considered to be the first week of the follicular phase. This is when there is bleeding and shedding of the uterine lining, and luteinizing hormone (LH), follicle-stimulating hormone (FSH), and progesterone are at their lowest levels. By the second week of the follicular phase, menses has ended, and estrogen and progesterone levels slowly begin to increase.

Around mid-cycle (typically about day 14), estrogen and LH spike, indicating ovulation. An egg is then released, which is when a woman can become pregnant. After this short window, the onset of challenges or frustration with exercise can begin, otherwise known as the luteal phase.

The Luteal Phase

For an active female, this is the phase that tends to have the most noticeable effects on her body. The luteal phase is considered the high-hormone phase, because both estrogen and progesterone are typically elevated, resulting in a multitude of the infamous effects known as PMS: cramps, back pain, headaches, mood swings, bloating, food cravings, fatigue, and upward of 100 other symptoms relating to hormonal changes. Although symptoms and severity can range, one study found that 90 percent of women experience PMS symptoms,1 most commonly in their 30’s.2

High hormone levels can cause other physiological changes that make exercise feel more difficult. During the luteal phase, a woman might notice a weight increase or at least feel like she is heavier. A rising progesterone level can activate aldosterone, a hormone that signals the kidneys to hold onto water and salt. The water retention is noticeable in body parts like the breasts, abdomen, or limbs and can make fitted athletic gear feel too tight and uncomfortable in addition to feeling heavy and sluggish in general. Hence, the body requires more effort to do the same work when you weigh more.

Progesterone acts on the hypothalamus and raises body temperature about one degree during this phase compared to other phases of the normal cycle,3 making sleep, exercise, and everyday tasks a bit hotter and sweatier. Although body temperature is useful to track cycles for fertility, having a higher body temperature can increase heart rate and respiratory rate, pushing the woman into more of a carb-burning state than is observed in the more fat-burning phases of the cycle. While exercising, body temperature increases to meet physical demands, so the body must work harder to cool itself.

While pain tolerance is highest during the follicular phase, a woman tends to be more sensitive to pain during the premenstrual luteal phase.4 This can make exercise feel more difficult or take longer to recover from, or both, which can completely change a woman’s mindset to training or competing.

For active women or female athletes, follow these tips to support and minimize PMS effects on exercising.

For the 5-10 days before your period:

Thorne’s Magnesium Bisglycinate will support sleep, promote relaxation, support healthy heart rate and rhythm, and promote blood vessel dilation, which in turn supports maintaining blood pressure and enhancing blood flow.* Mix one scoop of powder into a small volume of water and consume nightly before bed.

Iron levels can drop during menses because of blood loss from shedding of the uterus lining. To help maintain healthy red blood cell volume during menses, consider Thorne’s Iron Bisglycinate in the weeks before so you can maintain the normal uptake of oxygen into these cells.*

Consider eating fatty fish or taking Thorne’s Super EPA, a fish oil supplement that supports mood.* Consistency with fish oil is key, because research shows consistent intake of omega-3 fatty acids can minimize PMS symptoms and improve quality of life in women ages 20-35.5*

For abdominal cramps during this time, Thorne’s Meriva 500-SF can provide relief from muscle soreness and support a balanced inflammatory response in the muscles.*

For support pre-exercise:

Thorne’s Amino Complex is a blend of essential and branched-chain amino acids that can be taken pre-workout. Several amino acids can cross the blood-brain barrier and support brain function.* Tyrosine, for example, is a component in the production of several important brain chemicals like epinephrine, norepinephrine, and dopamine – supporting good vibes to complete a workout.

During exercise:

Recognize your body is going to use more carbohydrates as a fuel source. Depending on the intensity, duration, and volume of exercise, you might need to eat more carbohydrates than usual to support the same exercises. 

And with a higher body temperature, you might be sweating more or expiring more water with every breath. Thorne’s Catalyte provides optimal electrolyte balance for pre-, during, or post-exercise and will replenish the micronutrients lost through sweat and support rehydration.*


As you would need during any menstrual phase, protein is an important macronutrient to ingest post-exercise to jumpstart recovery and break the catabolic state. Thorne’s Whey Protein Isolate provides 21 grams of protein; is low in sugar, calories, and fat; and is easy to digest. It contains approximately 2.3 grams of leucine per serving, the amino acid that signals muscles to recover and repair after a workout.*

Want to learn more about your hormones? Thorne’s at-home Fertility Test measures the reproductive hormones mentioned above pertaining to the menstrual cycle, along with thyroid and adrenal hormones for an in-depth look at your personal hormone levels.

Although a “normal menstrual cycle” is hard to define because every woman varies in her cycle and many use birth control methods that affect the cycle, this blog is meant to educate and empower a woman to understand her cycle better.


  1. Winer SA, Rapkin AJ. Premenstrual disorders: prevalence, etiology and impact. J Reprod Med 2006;51(4 Suppl):339-347.
  2. Dennerstein L, Lehert P, Heinemann K. Global study of women’s experiences of premenstrual symptoms and their effects on daily life. Menopause Int 2011;17(3):88-95.
  3. Simmons RG, Jennings V. Fertility awareness-based methods of family planning. Best Pract Res Clin Obstet Gynaecol 2020;66:68-82.
  4. Hellström B, Anderberg UM. Pain perception across the menstrual cycle phases in women with chronic pain. Percept Mot Skills 2003;96(1):201-211.
  5. Behboudi-Gandevani S, Hariri FZ, Moghaddam-Banaem L. The effect of omega 3 fatty acid supplementation on premenstrual syndrome and health-related quality of life: a randomized clinical trial. J Psychosom Obstet Gynaecol 2018;39(4):266-272.