How much protein do women athletes need?
When it comes to nutrition and fueling their pursuits, many athletic women know they need more protein.
The poor recovery, muscle soreness, loss of lean mass, and lack of training progress you may be experiencing can have several causes.
But when I talk to women athletes over 40, the two most common fueling issues come down to protein and carbohydrate intake.
In this article, you’ll learn how much protein do women athletes need and how to prioritize protein for building muscle and strength.
- Protein: The Most Important Macronutrient for Building Strength and Muscle
- 1) Are You Eating Enough Total Protein?
- 2) Are You Distributing Protein Evenly Across the Day?
- 3) Are You Eating High-Quality Protein?
- 4) Are You Timing Your Protein Intake Around Training?
- 5) Prioritizing Your Daily Protein Intake
- Protein Intake for Women Athletes Summary
Protein: The Most Important Macronutrient for Building Strength and Muscle
The most common questions I get on protein are usually some variation of the following:
- How much protein do women athletes need?
- How much protein should I eat at each meal? Is increased protein necessary?
- What is the best source or type of protein I should be eating/using?
- Should I be having protein before, during, or after my workouts?
These common questions fall into four key aspects of protein intake when it comes to building strength and lean body mass and impacting athletic performance:
- Eating enough total protein
- Distributing that protein evenly across the day
- Ensuring high protein quality
- Getting protein around your workouts (i.e. specific pre/mid/post-workout meals)
Assessing these four pillars can give you a strategy to improve muscle mass, strength and performance during higher intensity exercise.
1) Are You Eating Enough Total Protein?
When it comes to muscle repair, recovery, and growth, eating enough total protein each day trumps all else. (1)
It’s not uncommon for female athletes, who are trying to build muscle and strength, let alone get through all the demands of the day, eating less than half the recommended amount of protein you need each day.
You may even get tied in knots over what types of protein are best, and how much you should have before or after a workout.
Not enough protein is not enough protein, no matter how you slice and dice it.
Calculating Protein Intake
If you require 100-120g of protein per day, but are consistently eating less than 60g most days, then it doesn’t matter terribly much how you’re dividing that across the day.
Taking an already small intake and further thinning it out across the day, eating it in small amounts here and there, works against you when it comes to building muscle and strength.
Historically, total protein recommendations have been given as a relative percentage of total calories, with between 15-25% being the most common range given. (2)
However, as you have an absolute requirement for protein, calculating your need using a percentage of calories can lead to wildly varying numbers.
For example, 15% of 1200 kcal – 45g – is quite a different absolute amount compared to 15% of 2500 kcal – 94g.
When calorie intakes drift lower and lower, the relative percentage approach could mean under-eating protein and overall energy.
How Much Protein Do You Need for Muscle Building?
Thankfully, there is growing acceptance that the commonly cited recommendation of 0.8 grams per kilogram body weight per day is insufficient for almost everyone in the population (3) and certainly athletic women over 40.
Most research available right now points to a total protein requirement between 1.4 g/kg and up to 3.0 g/kg in some cases (1), depending on goals and health status.
If a female athlete is undergoing a short term, hypocaloric diet for weight loss reasons, keep protein intake on the higher side and do resistance training to minimize losses in lean muscle mass.
This is a general range, and where you ultimately sits on this range will also depend on whether you are calculating intake using total body weight or lean mass.
What About Protein for Women Athletes Specifically?
We need much more research is needed on women athletes regarding sports nutrition and exercise performance.
According to the 2021 Invisible Sportswomen study, only 6% of sports and exercise studies conducted between 2014 and 2020 were performed on women-only cohorts.
However, a 2021 review in the Journal of the International Society of Sports Nutrition (4) covering female-specific recommendations notes these key points:
- During the mid-luteal phase, protein requirements may be higher due to an increase in protein oxidation.
- During exercise in the mid-luteal phase, protein usage appears to be higher.
- More protein is used for building endometrial tissue in the mid-luteal phase.
- Female athletes may require general protein intakes of 1.6-2.0 g/kg bodyweight per day.
Additionally, estrogen fluctuation and eventual decline during peri-menopause needs consideration.
Estrogen has strength- and muscle-building effects on skeletal muscle. During the menopause transition and beyond, the loss of muscle mass appears to accelerate.
A strong case can be made that female athletes over 40 should aim toward the higher end of the protein intake range of 1.6-2.0 g/kg bodyweight per day.
This, along with other practices shared in this post, helps tip the balance toward muscle protein synthesis and away from muscle protein breakdown.
2) Are You Distributing Protein Evenly Across the Day?
To understand the importance of protein distribution, particularly to muscle and strength development, you need a quick and dirty lesson in muscle protein balance.
Our body is always balancing muscle protein synthesis [MPS] with muscle protein breakdown [MPB].
What is Positive Protein Balance?
Muscle protein synthesis is what you want to rebuild and repair your muscle mass (a positive muscle balance state or anabolic response).
If there isn’t enough energy available to the body (both in the form of protein and non-protein energy), the net balance is shifted toward muscle protein breakdown (a negative muscle balance state or catabolic response).
MPS is extremely energy dependent, requiring both sufficient protein energy and sufficient non-protein energy (sufficient carbohydrate for the most part) for the balance to swing toward building muscle. (5)(6)
This is why an adequate carbohydrate intake, alongside sufficient protein, is considered “protein-sparing” (7). It prevents the balance tipping toward muscle protein breakdown.
Building muscle takes place in two major phases;
- The initiation phase – an analogy is getting all the tools and materials together before building a house.
- The elongation phase – this is where the building takes place (this is the part which requires a lot of energy). (8)
The MPS initiation phase is on a trigger-threshold system.
That is, the trigger needs to be at a specific threshold for your body to initiate building and repairing muscle.
If that trigger is below the required threshold, then muscle synthesis doesn’t occur. When it comes to how much protein women athletes need, getting enough leucine is one key goal.
How Does Leucine Trigger Protein Synthesis?
The trigger is a specific amino acid: leucine.
(Remember that amino acids are the building blocks of proteins.)
You need to reach the “leucine threshold” for MPS to start.
The leucine threshold is thought to occur when you eat ~3g of leucine PER MEAL.
(No, my caps lock wasn’t stuck there.)
To get this in a meal, you’re looking at the equivalent of a 6oz (165g) steak or a 4oz (100g) chicken breast.
This leucine threshold is why protein distribution is a close second to total protein in terms of importance when it comes to protein energy balance.
Let’s go back to the some common patterns I see.
If you’re skipping meals, whether intentionally or otherwise, or eat very small protein portions, it’s unlikely you’ll get enough protein in that meal to hit the leucine threshold. Muscle protein synthesis will not be triggered.
Skewed protein energy distribution across the day is common.
This is where you stack the vast majority of protein at one end of the day. More often than not, this is in the evening at dinner.
Part B of graphic below highlights the typical pattern I see with most clients when they come to work with me.
Adapted from Layman (2)
A Skewed Protein Distribution
You can see in distribution [B], two-thirds of the total protein for the day is consumed in one dinner meal. This meal provides enough leucine to trigger MPS.
However, because the trigger is ‘all-or-nothing’ and occurs with ~3g of leucine, adding more than this doesn’t give you more muscle synthesis.
[As an aside, when I ask people to recall if they eat enough protein, they tend to remember the dinner meal. If they eat a significant protein at this meal, they’ll tell me they eat “plenty of protein”. What they forget about is the rest of the day.]
In distribution B, neither breakfast nor lunch provide enough leucine to hit the threshold. MPS would not be triggered after these meals.
This delays muscle repair and recovery, and limits the opportunities across a day to maximize muscle protein synthesis.
If, across a day, you only spend the period after one meal in muscle protein synthesis, but spend the rest of the time in muscle protein breakdown, you’ll likely drift backwards over time.
Over the long haul, this can contribute to the loss of lean mass, with all its downstream consequences (including to your metabolism).
How to Spread Out Protein Intake
A more optimal protein intake distribution is shown in part [A] above.
Here, the same amount of total protein is consumed across the day (90g), but it is evenly distributed across 3 meals, with each containing sufficient leucine to trigger MPS.
Once MPS is triggered, it will tend to ‘run’ for 1.5-2 hours before dropping back to baseline.
This drop back to baseline occurs whether there’s a constant supply of amino acids to the system or not. Building muscle is such a resource intensive process that it can only run in short bursts.
Eating evenly spaced protein-dense meals with enough total energy to support the full process allows muscle protein synthesis to occur several times across a 24-hour period.
This makes it more likely that the overall balance will be tipped in favor of building muscle rather than breaking it down.
How Much Protein Should an Athlete Eat?
Let’s do a couple quick calculations to determine how much protein women athletes need.
For a 70kg woman, this translates to 28-38.5g of protein per meal.
To make life easy, I generally recommend that most 40+ women aim for 30-40g of high-quality protein in a meal, across at least 3 meals per day.
“Forty grams of protein in a single meal? But I thought the body can only absorb <insert commonly cited upper limit of protein absorption> at any one time?” you’re probably asking.
How Much Protein Can Be Absorbed in One Meal?
I hear these a lot: The body can only 20/25/30 grams of protein in one sitting. Anything above this amount would be used for energy (oxidation). Or worse, that protein will just sit in your gut where it starts to rot.
Fortunately, researchers have been able to science the shit out of such beliefs only to find they just don’t hold up to scrutiny.
No matter what dose of protein you ingest, some of the amino acids within the protein foods will be directed toward oxidation.
By eating higher amounts of protein in a meal, more amino acids will be oxidized for energy, though a degree of proportionality is maintained.
Keep in mind that protein costs you more energy to break digest and absorb (the Thermic Effect of Food). Therefore, some of this additional protein energy is likely directed toward the digestive system’s energy needs.
Many factors ultimately impact how much protein can be digested, absorbed, and utilized. However, research to date shows that the ‘protein ceiling’ is much higher than is commonly cited in ‘protein lore’ (as high as 0.6g/kg in older adults). (9)
Interestingly, one of the factors affecting how much ingested protein gets used for energy rather than muscle protein synthesis is protein quality.
3) Are You Eating High-Quality Protein?
Of all the sections in this article, this is the one I’m most hesitant about tackling.
Let’s look at the role of plant-based proteins in how much protein do women athletes need.
In order to address protein quality, I have to address animal source protein foods and plant source protein foods.
I come at this from a purely nutritional standpoint.
It’s not my place to make moral or ethical arguments for or against one type of protein source over another. It’s up to you to figure this out for yourself, based on your own personal values.
What I’m addressing here is physiology and performance.
Once you have the information, you’re free to integrate it with any information that resonates with you on morality and ethics, and make your own choices from there.
How to Define Protein Quality
In nutrition science, protein quality is defined as the ability of a dietary protein to meet the needs for regular metabolism and maintenance or growth of body tissues in humans.
Because the human body requires a regular supply of all nine essential amino acids (EAA) to synthesize body proteins (as in those used for muscle), protein quality metrics have been based on the content of essential amino acids in a food and includes, importantly, their digestibility.
Since the early 1990s, protein quality has been measured using the Protein Digestibility Corrected Amino Acid Score (PDCAAS).
What is Protein Digestibility?
More recently, it’s been proposed that the PDCAAS be replaced by another multi-letter acronym, the DIAAS – Digestible Indispensable Amino Acid Score. (10)
For simplicity sake, ‘indispensable amino acids’ and ‘essential amino acids’ are interchangeable terms. The main improvement of the DIAAS over the PDCAAS is that the former better takes into account the digestibility of specific food sources of amino acids.
Taking a deep dive into these scores is well beyond the scope of this article (and likely well beyond the interest of you, dear reader).
But what we can broadly say is that animal source foods all invariably rank highly on both types of scoring, while, with a couple of notable exceptions, plant-based protein foods rank low to moderate.
That is, animal source protein foods tend to have higher protein quality scores than plant-based foods.
How to Get Enough Leucine from Plant-Based Protein
If you’ve made the decision to use plant-based proteins as your predominant or only protein source, then any limitations of quality could potentially be overcome, at least with respect to protein (micronutrient density is another issue), by increasing the total amount eaten and ensuring a good distribution. (11)
Within the pool of nine essential amino acids, there are three which are especially important for muscle synthesis: isoleucine, valine, and leucine.
Remember that you need enough leucine in order to trigger muscle protein synthesis, around ~3.0g per meal.
The table below offers an excellent summary of what this looks like in terms of actual food amounts.
For example, maize (corn) is often held up as an example of a plant-based source containing a very high percentage of leucine.
From the table above, you can see that to hit ~3g of leucine in a meal – a more reasonable target for older people who require more leucine to trigger MPS than younger people – you’d need to eat 25g of maize protein.
This doesn’t sound like a lot until you see how much you actually need to eat to get 25g of protein from corn: 264g.
Consuming this amount of corn, just to get enough leucine in ONE meal to trigger muscle protein synthesis, means you’ll also be getting about 166g of carbohydrates.
In other words, with many of the lower-quality plant-based proteins, you can theoretically make them work by simply increasing more of them to hit your protein energy targets.
However, you’ll invariably have to increase your non-protein energy intake (predominantly carbohydrate) to do so. This can make achieving energy balance across the day trickier.
The Role of Plant-Based Isolates
Indeed, important to acknowledge that in research where the gap between plant-based and animal-based proteins has been closing (especially in human studies):
- the plant-based protein sources studied are invariably protein isolates (concentrated powders) such as soy protein isolate or pea protein isolate (the highest quality plant-based protein sources), and rarely any whole food source.
- that while increasing the total amount consumed of plant-based proteins may be a useful strategy to overcome protein quality limitations, this is only a theoretical compensation, and not all research supports this strategy;
“…we argued that the ingestion of greater amounts of plant-based protein per meal, consequently ingesting greater amounts of EAAs (and notably leucine), may compensate for the lower muscle anabolic properties of plant- vs. animal-based proteins…
…[R]ecent data suggest that the consumption of greater amounts of plant-based proteins, as a strategy to maximize postprandial MPS rates, may not per se provide a feasible solution. More specifically, Yang et al. reported that leucine oxidation rates were elevated after the ingestion of 40 g soy protein when compared with the ingestion of a similar amount of whey protein in older individuals.
These findings suggest that part of the soy protein–derived AAs are directed more toward oxidation than used for…MPS when compared with whey protein ingestion. Moreover, because 20 g whey and soy protein did not maximize the postprandial MPS response in these older individuals, the study provided further evidence to support the idea that aging muscle requires more leucine to maximally stimulate MPS rates.”Source: The Skeletal Muscle Anabolic Response to Plant- versus Animal-Based Protein Consumption
Okay let’s summarize this in common language.
Theoretically, you can compensate for the lower quality of plant proteins by increasing the absolute amount of them being ingested in a meal. However, there seems to be something inherent to these plant proteins which directs them to energy usage (oxidization) rather than muscle protein synthesis.
Also noteworthy is that more leucine, not less, is likely required as we age. If you’re a woman over 40, take note.
So, if you want to optimize muscle protein synthesis and thus your strength and muscle development:
- choose high-quality proteins
- eat plenty of them
- distribute them relatively evenly over your day.
If you have to compromise with, say, your daily protein energy distribution, only eating 1-2 larger meals per day, then it’s wise to make sure your total protein intake from high-quality sources is on point.
What I see often is low total protein intake, distribution across the day is skewed, AND a large reduction in animal protein.
This inadvertently lowers your protein quality quite significantly and means you’re not seeing the results you want from your training.
4) Are You Timing Your Protein Intake Around Training?
The final pillar in how much protein women athletes need is determining whether peri-workout protein is something you need to think about.
Put another way, why is protein important for athletes, specifically when it comes to eating it around your workouts?
That specific protein timing is even a topic for discussion most likely stems from bodybuilding circles where the concept of an ‘anabolic window’ has long been debated. (12)
If you’re training for competition-levels of muscle hypertrophy, is there a magical post-workout window (e.g. 30 minutes), where, if you ingest protein, you maximize muscle protein synthesis?
Like many topics in nutrition, whether any specific timing of protein intake is going to be relevant to certain individuals, depends.
Whether there is such a narrow post-workout window for getting nutrients in – protein or carbohydrate – is a topic still being debated.
The Protein Window
However, the most recent consensus seems to be that the tiny window is more of a “barn door.” It’s less likely measured in short minutes and more likely in terms of a few hours.
If your total protein intake is optimal, you’re eating 3-5 higher protein meals distributed over the day, and your protein quality is high, then specific protein timing isn’t the utmost important for most people.
Spreading your meals out across the day means there’s a good chance one will fall into what we might call a “pre-workout window” and another will likely naturally fall into the “post-workout window.”
How we slice and dice the exact timing – ex: is getting some protein at 15 minutes or 30 minutes post exercise – is less definitive.
But what I can say with certainty is that not eating either side of a workout, a habit of fasted hard training, and getting so distracted post-workout that you don’t eat for hours, is distinctly disadvantageous to the vast majority of women athletes I work with.
Protein Intake at Breakfast
Perhaps one area where specific timing is advantageous is the protein intake at breakfast.
A 2021 paper (13) showed that the timing and distribution of a higher protein intake at breakfast compared to dinner was positively correlated with strength and skeletal muscle volume in healthy older women.
This finding held up even when breakfast protein was high and dinner protein was lower. This points to a circadian rhythm component to how our bodies utilize protein for muscle growth.
Again, this is the opposite pattern from what many women do (with higher protein at dinner and minimal protein at breakfast).
Anecdotally, when my clients make a concerted effort to get a good protein-centered breakfast, they have much more stable energy and appetite control across the day.
5) Prioritizing Your Daily Protein Intake
Let’s recap the four pillars discussed here for how much protein do women athletes need:
- Total protein intake
- Daily distribution
- Protein quality
- Specific timing
It’s important to point out that these are interdependent variables. Changing one will have an impact on the others.
Practical Recommendations for Protein Intake in Female Athletes
If you need direction, then I recommend the following:
- Ensure that your total protein intake is at least 1.6g/kg
- Consume at least four meals of 0.4g/kg/per meal, distributed evenly across the day (giving a total intake of 1.6g/kg for the day)
- Keep protein quality high with a bias toward protein-dense animal source foods. Please don’t forget that plants are a vital part of a nutritious diet, as is meeting fiber minimums.
- Eat one of those 0.4g/kg protein meals at breakfast, and one after your main training session for the day (if your breakfast doesn’t already cover you here).
This is a process so have patience. You’ll likely have to change several habits in terms of shopping, meal prep, and actually eating.
With that in mind, I recommend you focus on individual meals. Start with breakfast first, getting protein levels and type adjusted, and stacking meals over time.
If you eat higher quality animal source proteins – meat, fish, poultry, eggs, dairy, and their supplemental protein sources, such as beef protein powder, egg white powder, and whey – then start with 0.4g/kg per meal.
For a 70kg woman, this equals 0.4 x 70 = 30g of protein in a meal (rounded up).
Plant-Based Protein Tips
If you’ve decided to choose plant-based proteins, I recommend using isolate powders. Examples are soy or pea/rice (Plant+ from Legion is delicious).
You can have these alongside your main whole food meal. Start with a per meal amount of 0.55g/kg.
For a 70kg woman, this equals 0.55 x 70 = 40g of protein in a meal (rounded up).
Your first such meal would be at breakfast and not delayed until the afternoon
Depending on your overall goals, level of training, schedule, etc., aim to eat 3-5 of these meals across the day.
Most people are home in the morning around breakfast time, and home again at night around dinner time.
Dial in these two meals, using them to bookend your day.
If the rest of your day has good structure, plan your remaining meals between breakfast and dinner to suit your schedule accordingly.
Protein Intake for Women Athletes Summary
In this article, you’ve learned four key factors to help answer the question, “How much protein do women athletes need?”
It’s important to keep in mind:
- Eating enough total protein
- Distributing that protein evenly across the day
- Ensuring high protein quality
- Getting protein around your workouts (i.e. specific pre/mid/post-workout meals)
Increasing your protein intake isn’t the easiest thing to do. It usually takes planning, prep work, and awareness. You’ll have to build new habits.
However, taking one step at a time, and prioritizing dietary protein intake will positively benefit your training, post exercise recovery, and athletic performance as a woman over 40.
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