The Importance of Protein for Female Athletes

'Women are not small men' - when I heard these words and the accompanying Ted Talk by Dr. Stacy Sims, my perspective on nutrition and training changed. Something clicked. It made sense why some weeks I felt awful and sluggish and couldn't seem to lift heavy, whereas others I was bouncing off the walls and getting in multiple sessions.

Between the information put out by Dr. Stacy Sims and the menstrual tracking app FitrWoman, my eyes opened to the physiological differences between men and women; in particular, the role that our hormones play throughout our cycle.

The importance of protein and it's role in recovery, especially during the high-hormone phase when we are more catabolic was another shift in perspective. Of course, I was aware of the importance of protein and the dangers of RED-S (relative energy deficiency in sport) from my own studies and working in the fitness industry, but I was not up to speed on the specific considerations for the female physiology. Cue me devouring anything I could get my hands on around the menstrual cycle and female physiology, including the brilliant online course by Dr. Stacy Sims.

In my bid to support the movement of sharing this knowledge with other active women and other coaches, I have collated a list of recommendations below, highlighting the importance of protein for female athletes.

Why does Protein Matter for Women? - Goal Specific

What is it?

Protein is one of the three main macronutrients (protein, fats, carbohydrates) that your body needs to get from food. Protein is made up of amino acids, which are considered the body’s ‘building blocks’ because they form the basis of many important molecules in our bodies (cells, hormones, neurotransmitters, etc.)

Why does it matter?

Protein is essential for maintaining a strong immune system, optimum recovery after exercise, increased athletic performance, as well as body composition. We need a supply of amino acids circulating in our blood so that our body can use them to repair and build our bodies, especially after exercising.

Female Turkish Get Up

Here is brief overview of why protein is important for different goals that you may have:

1. General Health:

As mentioned above, protein forms the building blocks of your body. An adequate amount of protein is needed just to fuel daily living, ensuring a strong immune system, adequate energy, and a healthy metabolism.

2. Body Composition:

Protein is essential for building muscle as your body uses the protein that you eat to build and repair your muscles after resistance training. Increasing your body’s lean muscle mass will not only improve your body composition, it will also increase your resting metabolic rate. This means the more muscle you have the more calories you will burn simply by existing. Your body uses more calories to break down the protein that you eat than carbs or fats.Protein is highly satiating, which means your body finds it satisfying and filling to eat. Protein is important to make sure you do not enter too much of a deficit when trying to lose body fat. Having Low Energy Availability (LEA - which is very common for women), can result in your body slowing down, holding on to weight, and increasing the stress hormone cortisol, which increases fat storage around the midline.

3. Fuelling Sports and Exercise Performance

Doing high intensity training or heavy resistance training sessions will put your body under stress. The amino acids in protein are essential for optimal recovery and performance.Eating enough protein to fuel your activity levels will make sure you avoid going into Low Energy Availability (LEA) or even Relative Energy Deficiency in Sport (RED-S), which is very common amongst female athletes and recreational exercisers. 45% of female recreational exercisers fall into the sub-clinical classification of low energy availability (Sims, 2019). Our bodies enter a catabolic state (muscle-break down) after exercise; ensuring that we refuel our bodies and muscles with protein after training is important to improve recovery and avoid RED-S. The timing of this post-exercise protein consumption is even more important for women than it is for men as Dr Stacy Sims states that our bodies "return to baseline" a lot quicker, whereas men have a longer ‘window’ to refuel.

Female Athlete Specific Considerations for Protein Consumption

The female hormones, oestrogen and progesterone, have different effects on muscle protein synthesis. Men do not have the same peaks and troughs of hormones as women, nor do they have the same hormones. The majority of recommendations about protein are based on male studies and generalised to women, which is not necessarily applicable due to our differences in hormones.

Protein Consumption

It is recommended that individuals consume 1.8-2.2g of protein per kg of body weight to maintain and/or grow muscle. For premenopausal women (eg. after puberty and before menopause) it has been shown that we have a higher need for protein, especially when resistance training.

Dr. Stacy Sims recommends eating 2.2g or more of protein per kg of body weight for premenopausal women.

Women also need a higher concentration of leucine (a specific branched chain amino acid) to trigger muscle protein synthesis, so pick protein sources with high amounts of leucine (whey, cows milk, beef).

Timing

Before Exercise: If having a hard/heavy training session, it is important to consume 15-20g of protein before you train. It has been shown that coupling protein consumption with hard training sessions can improve your body’s ability to make muscle out of the protein consumed (Sims, 2016).

Note: a gentle run or low-moderate session in the gym will not require a protein top up if you have eaten a meal 2 hours before, but you should not train fasted.

During Exercise: If you are training for longer than 1 hour, especially during endurance or heavy training sessions, it is recommended to consume some BCAAs (branched chain amino acids) during your session.
After Exercise: If you only do one thing, then do this! It is important to consume 25-30g of protein 30 mins post-session, making sure it contains 5-6g of BCAAs to reduce catabolism (muscle breakdown) and stimulate muscle growth. This avoids you going into a ‘catabolic’ (muscle breakdown) state which can impact recovery as well as negatively impact your body composition/mood/performance (Sims, 2019).
Throughout the day: It has been shown that consuming 30g of protein throughout the day with breakfast, lunch, and dinner gives a 24 hour window of muscle protein synthesis than consuming it all with one meal. Coach Darragh Henry of FFS has a great Instagram post on this which discusses this in more detail and he will be doing an upcoming blog post on the topic of protein.

The effects of your hormones on training and protein consumption:

Your hormones change during the course of your menstrual cycle and the different hormones affect how your body builds or breaks down muscles.

The female hormones, oestrogen and progesterone, have different effects on muscle protein synthesis.

Oestrogen is generally anabolic, meaning it helps to build muscle.
Progesterone is catabolic, meaning it breaks down muscle.

During the first half of your menstrual cycle (the low hormone phase), you are more anabolic and better suited to heavy resistance training and HIIT.

Both hormones are low during your period. This is when, hormonally speaking, we are most similar to men.
Oestrogen is high, without progesterone, during the first half of your menstrual cycle.

During the second half of your menstrual cycle (the high hormone phase), you are more catabolic and need to ensure sufficient recovery and nutrition strategies. We are also better suited to moderate intensity sessions.

Progesterone rises in the second half of your cycle meaning that recovery is a lot harder due to our bodies being more catabolic.
Consuming enough protein and refuelling after training session is very important during this stage to try to counteract this physiological change.

Putting it into Practice

Quick Tips:

Refuel with protein (complete protein source with the amino acid leucine) 30mins post-session, followed by a full breakfast (mix of carbs, proteins, fats).

Example: Have a protein shake with you in your bag for sessionsIf possible, go for whey protein and cows milk as they have a higher leucine content but do what is right for you.
Have a portion of protein with breakfast
- Protein powder - Scoop of whey protein with overnight oats/porridge, add it to a smoothie or make some mud muscle pancakes!
- Eggs - hard boiled, pre-cooked omeletteGreek yogurt, quark or skyr - pick a high protein source

Women need a higher concentration of leucine to trigger muscle protein synthesis, so pick protein sources with high amounts of leucine

Whey, Cows milk
Chicken, Beef,
Firm Tofu, Navy Beans,
NB - If choosing Vegan protein make sure it is a mixed protein and says it has a ‘complete protein source’ meaning it will have sufficient amounts of all 9 essential amino acids that your body cannot produce naturally, including leucine.Women need a higher concentration of leucine to trigger muscle protein synthesis, so pick protein sources with high amounts of leucine:

Don’t train fasted

Training fasted increases cortisol which promotes fat storage and can decrease the available building blocks needed for your other hormones, like progesterone.
Have something to eat 30-45 mins before training, especially if before a heavy training session
Fast releasing carbohydrates and some protein (15-20g of protein)
- Slice of toast with natural peanut butter/nut butter protein mix
- Banana with natural peanut butter/nut butter protein mix
- Homemade energy protein balls

Additional Reading:

I would highly recommend reading Dr. Stacy Sims' book 'Roar' and downloading the FitrWoman app to track your menstrual cycle a. Both are incredible sources and would have informed a lot of my initial learning of the topic.

Great article by Precision Nutrition on Growing Muscle.
All about Protein by Precision Nutrition
Dr Stacy Sims on the importance of protein
Dr Stacy Sims on RED-S
MyFitnessPal & Danielle Omar (via Dr. Stacy Sims) on what 30g of Protein looks like
Want to find out more?

Contact Coach Sinead

If you would like to know more about the specific sources or want more information about training and nutritional recommendations for the female physiology (i.e. training with your menstrual cycle) or know more about 1:1 personal training, then please contact sinead@ffs.ie.

Sources

Women Are not Small Men | Female Sports Physiology & Performance, Online Course, 2019
Roar, Dr. Stacy Sims (would highly recommend), 2016
Period Power, Maisie Hill, 2019
FitrWoman App Insights
My Food Data - High Leucine Foods
Medical News Today - Essential Amino Acids
Precision Nutrition - All about Protein
Precision Nutrition - All about Muscle Growth

Email Sinead at sinead@ffs.ie.

Find Sinead on Instagram at @sineadbrophy

Sinead Brophy

Coach Sinead is a certified Personal Trainer, Movement & Mobility Coach, Modern Pregnancy & Postnatal Exercise & Wellness Trainer, and is trained in Female Physiology and Nutrition. Sinead is particularly interested in the female athlete, from how the menstrual cycle impacts training to coaching women in strength and aerobic training during pregnancy. Sinead is leading the way in Dublin in educating women about how to work with their bodies, to harness the power of their hormones, and get the most out of their training. Sinead is heading up Small Group Personal Training for Pregnancy in the new FFS location across the road from the Rotunda, FFS Ivy Exchange Parnell Street - Dublin 1. Email Sinead at sinead@ffs.ie. Find Sinead on Instagram at @sineadbrophy