nutrition and hormone health for female athletes
Proper nutrition and physical health is essential when living an active lifestyle. Athletes depend on the endurance and strength of the body and require adequate energy intake from quality foods to perform optimally.
Female athletes must remain mindful and protective of their unique and complex menstrual cycle fluctuations and hormone profiles. If the body is neglected (through under-eating and/or over-exercising), hormones become dysregulated, resulting in a cascade of biological changes and health concerns. Unfortunately, energy deficiency (inadequate energy intake in relation to energy expenditure) is prevalent among female athletes. My goal is to share information on this subject and help you identify or evade health complications rooted in inadequate female sports nutrition.
In this blog, I will discuss hormonal health and nutrition and their importance for female athletes. I will also share some tips for managing nutrition and hormonal health while playing sports/exercising frequently.
Other blog posts…
To learn more about overall nutrition, click here.
To learn more about women’s hormones, click here.
To learn more about female hormone fluctuations, click here.
To learn more about balancing female hormones, click here.
Looking After Your Hormones…
Important Hormones for Female Athletes
Testosterone: Essential for building muscle mass and increasing strength.
Cortisol: Regulates the stress response within the body; can affect the breakdown of muscles.
Estrogen: Crucial role in bone health and injury prevention.
Growth hormone: Vital for muscle growth and repair.
Thyroid hormones (TSH, T4, T3): Regulate energy levels and metabolism.
Insulin: Regulates blood sugar levels; affects muscle growth and repair.
Cortisol and Adrenal Fatigue
When you experience mental or physical stress (perceived or actual), hormone changes occur. As you exercise, the hormone cortisol is produced by the adrenal glands. The amount of cortisol released depends on your current state of health and the intensity and duration of the workout. The release of cortisol allows you to push through training sessions.
However, if an athlete overworks their body and/or under-fuels their body (lack of proper nutrition), cortisol is produced in excess. This causes adrenal fatigue, hormonal imbalances, and dysregulation throughout the body, hindering overall health and athletic performance.
You can read more about adrenal fatigue and cortisol here.
Natural Hormone Fluctuation
Women’s hormones fluctuate throughout the monthly menstrual cycle. This influences the nutritional needs and energy levels of women during the month. Natural hormone shifts explain why you may feel more energized and strong during the follicular and ovulatory phases (around two weeks after your period) and tired, emotional, and less motivated leading up to and during your period.
Staying mindful of this naturally occurring ebb and flow of hormones is crucial for female athletes; working with, not against, these shifts will help to optimize health and athletic potential.
Cycle Syncing
Cycle syncing the intensity of your workouts with the specific phases of your cycle can help to maximize exercise benefits and reduce the risk of burnout, pulled muscles, or stress fractures.
While it may not always be possible to change up your workouts when playing a sport, paying attention to the phases of your cycle enables you to understand why you may be performing or feeling a certain way; if you cannot modify the intensity of training, you can still take part in cycle synching outside of practice.
Understanding the phases of your cycle is vital when it comes to fueling your body with the nutrients and energy it needs to perform best. Throughout the month, the body requires different levels of certain nutrients to function optimally — this is crucial for reducing excess stress on the body and enhancing female athletic performance.
You can read more about this here.
Nutrition for Female Athletes
As with anyone, athletes should strive to eat a balanced diet full of various macronutrients (protein, carbohydrates, and fat), micronutrients (vitamins and minerals), and fluids. Athletes, especially, require optimal amounts of nutrients and energy (calories) to support growth, repair, and development.
Here is a rundown of crucial nutrients for female athletes…
Macronutrients
Protein: This macronutrient is needed for muscle synthesis (specifically the amino acid leucine). Protein is required for the growth and health of our hair, skin, and nails. It is vital for all enzymatic reactions within the body, such as the breakdown of macro and micronutrients and the regeneration of body tissue.
As a general recommendation, you should aim for around 20-30 grams of complete and quality protein at each meal. However, everyone has different needs depending on age, activity level, and menstrual cycle phase.
Carbohydrates: These are the body’s primary fuel source and are a crucial macronutrient for athletes. The amount of carbohydrates necessary depends on bio-individuality and the intensity of exercise (the higher the intensity, the more carbs you may need to fuel your body). High-quality carbohydrates are essential for maintaining physical performance and healthy metabolism. Quality carbohydrates also help regulate blood sugar levels, thus decreasing the stress response after exercise.
Fat: Healthy fats are vital macronutrients for everyone, especially females and female athletes. Fats are crucial to the absorption of fat-soluble vitamins such as vitamins A, D, E, and K. Vitamins A and E are potent antioxidants crucial for countering the oxidative stress caused by exercise. Vitamins D and K are essential for healthy bones. Fats (especially omega-3 fatty acids) help decrease inflammation and maintain muscle tone.
Be sure to include healthy fats at each meal; this could look like half an avocado, a spoonful of nut butter, or a drizzle of olive oil.
Micronutrients
Vitamins and minerals are crucial for the entire body and its functions. They play a key role in bone health and development, immune function, hormone balance, tissue regeneration, and energy production.
A deficiency in any nutrient negatively affects health and can prohibit a female athlete from reaching her goals. Unfortunately, many women are nutrient deficient for many reasons, including hormonal contraceptive use and inadequate nutrition.
However, with a strong basis of knowledge, you can prioritize the consumption of these crucial micronutrients.
Vitamins and minerals for athletic performance…
Folate (B9): Folate is the natural form of Vitamin B9. It plays a vital role in breaking down the amino acid homocysteine, which, if present in high amounts, can have harmful effects on the entire body and mind.
Folate is essential to the process of DNA methylation. DNA methylation is critical to normal genome regulation and development; it helps to protect DNA from oxidative damage or compounds created during intense exercise.
Sources of folate include beans, lentils, dark leafy greens, sunflower seeds, peanuts, whole grains, aquatic foods, eggs, and fresh fruits.
Calcium: Calcium is crucial for bone health and muscle function. The body needs adequate amounts of calcium for the muscles to move and for the nerves to transfer messages to and from the brain. Calcium also aids blood vessels in moving blood throughout the body while stimulating the release of crucial hormones.
Females are at a higher risk for weak bones than males due to fluctuating levels of estrogen. When estrogen levels are low, women are at risk of weakened bones and stress fractures. If the body has inadequate levels of calcium, it will take it from the bones, further weakening them.
A calcium deficiency in female athletes can cause muscle cramps, possible stress fractures, and premature fatigue.
Sources of calcium include organic dairy (cow, goat, and sheep), canned sardines, salmon (with bones), sesame seeds (tahini), leafy greens (spinach, mustard, kale, chard), almonds, molasses, winter squash, beans (kidney beans, chickpeas, white beans)
Magnesium: This nutrient is classified as an electrolyte and is imperative for maintaining athletic performance. Magnesium is essential for reducing muscle cramping and premature fatigue in athletes. Magnesium works to build proteins and strong bones while assisting in nerve and muscular functions. Furthermore, magnesium acts as an electrical conductor, contracting and relaxing muscles and ensuring the heart beats steadily. It helps improve sleep by relaxing muscles and calming the central nervous system.
Sources of magnesium include legumes, dark green veggies, nuts, seeds, beans, brown rice, oatmeal, salmon, grass-fed beef, chicken, bananas, raisins, dark chocolate (>70%), milk and yogurt.
Vitamin C (ascorbic acid): This vitamin triggers the production of new collagen, which improves joint, muscle, and skin health and repair. Vitamin C is a cofactor of the antioxidant glutathione; together, they help to protect the immune system and reduce oxidative stress.
Vitamin C is also an important cofactor for the adrenal cortex and adrenal medulla. Adequate amounts are vital for adrenal health; vitamin C helps prevent the adrenals from over-firing, which can lead to adrenal fatigue and burnout in athletes.
Sources of vitamin C include citrus fruits (orange, kiwi, lemon, grapefruit), bell peppers, strawberries, tomatoes, cruciferous veggies (cabbage, broccoli, Brussel sprouts, cauliflower), and sweet potatoes.
Other vital nutrients for female athletes include:
Vitamin B6 (vital for hormone balance and melatonin production)
Tryptophan (converts to niacin (vitamin B3); necessary for energy production and the metabolization of proteins and carbohydrates)
Iron (which aids in the transfer of oxygen to muscles)
Why is proper nutrition and hormone health so important for female athletes?
Females have unique hormone profiles and menstrual cycles; female athletes must consume adequate fuel to reduce excess stress on the body, foster hormone balance, and protect overall health and performance. Nutrition is not the singular factor in dictating hormonal health (stress management, recovery, and sleep are also vital). However, what you eat and your energy input relative to your energy expenditure significantly impact overall health and function.
Energy Availability, Exercise Energy Expenditure, and Low Energy Availability
Energy availability (EA) is the amount of energy left available for physiologic and homeostatic processes. EA takes into account exercise energy expenditure (EEE). When the body is not replenished with adequate energy relative to training (EEE), the body experiences low energy availability (LEA). Low energy availability (LEA) is when the body does not have the energy (calories) left to support all physiological functions needed to conserve optimal health.
Prolonged low energy availability puts athletes at risk of relative energy deficiency. Due to a high activity level, athletes are more likely to experience relative energy deficiency. LEA and energy deficiency lead to a cascade of hormone imbalances and health problems, all rooted in one significant factor — inadequate nutrition/energy.
Effects of energy deficiency and hormone dysregulation on female athletes…
Menstrual Dysfunction: When experiencing chronic low energy availability and energy deficiency, the body's natural homeostasis is disrupted. Within the female body, stress signals stimulate hormone changes that halt reproduction and, therefore, the menstrual cycle — luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen, and progesterone all become dysregulated.
Contrary to popular belief, losing your period as a female athlete is NOT normal — it is a sign of hormone dysregulation and dysfunction. Hypothalamic amenorrhea is when your hypothalamus signals your period to stop; this is commonly caused by chronic energy deficiency.
Amenorrhea, combined with low energy availability and low bone density, has been labeled “the Female Athlete Triad” because it is so prevalent within women’s athletics. Studies demonstrate many serious long-term consequences for athletes who struggle with a fraction of or all of this triad.
Bone Health: Healthy and strong bones require frequent physical activity, enough calcium, and balanced hormone levels. As mentioned before, women’s hormone fluctuations influence bone density — hormone health significantly impacts bone health.
Normal levels of estrogen in women work to preserve bone density. However, a drop in estrogen caused by hormonal imbalances catalyzes a rapid loss of bone mineral density (BMD). As shown in the female athlete triad, hormone dysregulation (ammonia) and low bone mineral density are somewhat interdependent. This loss in BMD leaves female athletes with a high risk for stress fractures and an increased chance of developing osteoporosis.
Elevated levels of circulating cortisol (high stress) rooted in undereating and over-exercising (low EA) are also cause for concern when it comes to bone health in female athletes. High cortisol levels can contribute to significant bone loss, stress fractures, and an increased risk of osteoporosis.
Musculoskeletal Health: With prolonged low energy availability, muscular protein synthesis is negatively affected. This is because of decreased anabolic hormones and increased cortisol levels, which initiate the breakdown of skeletal muscle proteins. This is a reason for chronically sore and achy muscles and a possible halt in athletic improvement. Low energy availability (and other parts of the Female Athlete Triad) puts a female athlete’s body at high risk for musculoskeletal injuries.
Downregulation of the endocrine and metabolic system: During chronic LEA, energy deficiency, and disordered eating, the body goes into an unsustainable survival mode, inducing a cascade of hormonal changes.
With LEA, there is a decrease in the hormone leptin. Leptin is known as the satiety (fullness) hormone — it is crucial in maintaining energy homeostasis. Leptin levels decrease early during food deprivation. There is also a decrease in insulin, insulin-like growth factor 1 (IGF-1), estrogen, progesterone, and triiodothyronine (T3).
These detrimental changes result in numerous health concerns for females and female athletes. Concerns include the following hypothyroidism (underactive thyroid) related symptoms: reduced resting metabolic rate, bradycardia (slower than average heart rate), hypoglycemia (low blood sugar), orthostatic hypotension (blood pressure drops when you stand up or sit down), high cholesterol, etc.
Early signs of low energy availability
Missing or irregular menstrual cycle
Mood concerns — such as depression or irritability
Fatigue
Frequent injuries such as pulled muscles or stress fractures
Frequent illness
Increased GI (gut) issues
A decrease or lack of training adaptations and progress (like you have hit a wall)
Tips for Female Athletes
Make BALANCED nutrition a priority: All women, especially female athletes, must eat three balanced meals a day. A balanced meal consists of high-quality carbohydrates, a high-quality source of protein, healthy fats, and fruits or veggies. For optimal health and performance, the body must be fueled appropriately with adequate micro and macronutrients.
BREAKFAST: Eating a well-balanced breakfast is a crucial start to the day. Eating breakfast reduces excess stress by balancing blood sugar levels and providing energy for every function within the body. A well-balanced breakfast within about an hour of waking up is vital for female hormone support. Breakfast should contain around 20-30g of protein, complex carbohydrates, and healthy fats.
For on-the-go mornings, consider prepping some breakfasts ahead of time to have when you wake up. Overnight oats, chia seed pudding, and hard-boiled eggs are excellent breakfast components that can be made beforehand.
What if I have a morning workout and can’t eat a full breakfast before? — Exercising on an empty stomach spikes cortisol levels. If you have a morning workout, opt for a balanced snack consisting of easy-to-digest carbohydrates and healthy fats. Some of my favorite pre-workout snacks in the morning are a couple of dates with nut butter or a banana with nut butter and cinnamon. After training, be sure to fuel your body with adequate macronutrients, including protein.
Say NO to dieting, low-carb, and restrictive eating: Restrictive, low-carb, and ketogenic diets are not healthy or conducive to female health and athletic performance. Carbohydrates are a crucial source of energy for female athletes; carbohydrates are the only macronutrient that can be broken down fast enough to fuel high-intensity exercise. Female athletes should consume quality carbohydrates in and around training. Research demonstrates athletes' indispensable need for carbohydrates, protein, and healthy fats.
Athletes need extra fuel depending on the intensity and duration of their workouts. Without this energy, athletic endeavors cannot be sustained. If you are experiencing LEA symptoms, increase your intake during/around training and throughout the rest of the day.
Begin your week by preparing meal components: Busy lives often leave too little time for making balanced meals, especially for lunch and breakfast. You can make this much easier by preparing meal components at the beginning of the week to have ready for breakfasts and lunches. Find a day when you do not have much going on to spend some time in the kitchen — Sundays are usually the least busy for me.
Plan out a couple of carbohydrates, protein, healthy fats, and vegetable meal components. For example:
Carbohydrates:
cook a big batch of quinoa or brown rice to use throughout the week
cut and bake some sweet potato wedges or cubes
I love to bake chickpeas ahead of time to use as a crunchy addition to my meals (rinse some chickpeas, dry them off, coat them in olive oil and seasoning, spread them out on a baking sheet, and bake)
Protein:
cook a few chicken breasts — you can shred them or cut them and add them to meals throughout the week
hard boil eggs to use for breakfast or lunch
make a batch of ground beef or bison to use for taco bowls
cook some lentils or quinoa in bone broth
Vegetables:
bake a batch of cauliflower and broccoli
make a big kale salad
saute some bell peppers with onions (can create fajita bowls with chicken, rice, and avocado later)
wash your produce and store it for later
Healthy fats:
make a salad dressing or sauce ahead (my favorite is tahini with lemon juice, turmeric, black pepper, and sea salt)
have some avocados, nut butter, and olive oil on hand — they make an easy addition to meals
Cycle Syncing: Try to stay mindful of your unique menstrual cycle phases. With this knowledge, you can practice syncing your habits with your natural hormone fluctuations. Remaining cognizant helps you understand why you may be feeling a certain way.
As mentioned before, even if you cannot adjust your workouts, you can modify your habits outside of training. Nutritional, sleep, and emotional needs fluctuate throughout the month and are vital to overall health and athletic performance.
You can read more about hormone fluctuations and cycle syncing here.
Remember…
Having struggled with disordered eating and over-training in the past, I have first-hand experience with health complications such as hypothalamic amenorrhea. While these things may not seem like a big deal, I can attest to the fact that they are serious and can lead to detrimental health problems and an inability to participate in sports if left unchecked.
There is no one body type for an athlete. Being healthy does not mean looking a certain way. Healthfulness is found when your body and mind are adequately fueled, allowing your hormones to remain balanced. You will perform best at your healthiest and “health” looks different on everyone.
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