Carbohydrates for active women athletes is a tricky subject to discuss these days.
There are opposite views everywhere you look. And carbs continue to have a bad reputation in many camps.
But as a female athlete, carbohydrates aren’t an enemy. Rather, it’s important to understand their role in training and how to use them to your advantage.
This article lays out an introduction into carb intake controversies and concepts for athletic women.
Further articles about the practical applications will be based on this foundation.
In this article you’ll learn:
- Why Women Athletes Need to Fuel
- Carb Intake and Energy Balance
- Lower Carb Taking the Credit for Higher Protein
- Advanced Nutrition Tools and Carb Intake
- Drawbacks of Low Carbohydrates for Women Athletes
- What About Low Carb Intake, High Fat?
- What is Gluconeogenesis?
- Is High Fat Practical for High Intensity Athletes?
- Nutrition Versus Fueling – What’s the Difference?
- Amounts and Timing of Carbs
- Summary of Carbohydrates for Women Athletes
Why Women Athletes Need to Fuel
Context is crucial when discussing carbohydrates for women athletes.
To grasp the context of this article, you must understand who I work with: women who want to fuel their strength and performance.
These highly active women also tend to be ‘super moms’, juggling family, caring, career, and their own athletic endeavors.
Most are training four or more days per week.
You lift heavy weights. And your conditioning often focuses around CrossFit, Peloton, and other high-intensity activities that last about an hour or less.
Importantly, when you look at it from a metabolic fueling point of view, the vast majority of your physical activities occur along alactic, anaerobic and aerobic (1) glycolytic pathways. You need adequate glycogen stores to support that kind of activity level and intensity.
The breakdown of glycogen to glucose for energy is the predominant metabolic pathway fueling your training.
Time domains for your efforts are measured in seconds and minutes, not several hours. (I rarely work with endurance or ultra-endurance athletes.)
In my community, there’s still a dominant belief is that carbohydrates are to be feared and avoided because they cause weight/fat gain.
As a nutrition professional, I know not to assume that everyone’s goal, when coming to work with me, is intentional weight loss. Likewise, not every nutritionist focuses on guiding intentional weight or fat loss.
I focus on helping women improve their performance, strength, and muscle mass. Assume that’s the context I’m writing from.
Despite a high energy output – both structured training and their daily life – you’re often under-fueled. Macronutrient-wise, that can look like:
- low protein
- low carb
- low fat or high fat
Combine low total energy intake with large within day energy deficits, and a majority of my clients arrive in a low energy availability state.
Despite this, there’s a reluctant to eat more – especially more carb intake.
Carb Intake and Energy Balance
I don’t want to get bogged down unpacking every topic of carb confusion and controversy.
Taking a 30,000 foot view and a performance principles approach will address a big chunk of the important issues.
Let’s revisit a slightly more nuanced view of energy balance. (For a detailed article, see Calories In, Calories Out – What’s the Deal?)
Total Energy = Protein Energy + Non-Protein Energy
Recall that non-protein energy largely means carbohydrate energy and fat energy. Thus, the above equation becomes:
Total Energy = Protein Energy + [Carbs + Fats]
Energy balance – and staying out of a low energy availability state – means eating enough protein energy and enough non-protein energy.
Many athletic women over 40 are:
- often in a low energy state AND
- either trying to lose body fat, or trying to stay lean and not gain body fat.
You follow the persistent narrative that, for fat loss, they have to eat even less and train even more. Yes, you need a caloric deficit for fat loss or reducing body weight while sparing muscle.
However, that deficit cannot be drastic. Protein intake must be high. And resistance training must be performed.
As a side note, the risk of insulin resistance tends to increase with age, and this may contribute to the over 40 athletic crowd largely avoiding carbohydrates.
However, it’s not an automatic, foregone conclusion. There are a lot of things in your power to influence such as regular exercise, reducing stress, selecting mostly high-fiber, complex carbs, and so on.
“Eat less, move more” may have started in the 1980’s with low fat diet and lots of aerobics.
But today it’s more common to see carb restriction with tons of weights plus moderate to high intensity interval training. (Ironically, intense training requires carbohydrate as the primary fuel source.)
Both strategies – low fat versus low carb – have their supporters and naysayers, but the reality is more nuanced than that.
Lower Carb Taking the Credit for Higher Protein
If a person eats a Standard American Diet (SAD), this is often high in the most ultra-processed versions of BOTH carbohydrate AND fat.
Let’s say that person begins following a low-carb ancestral style diet. Maybe there’s a bit of complex carbs thrown in, but not much.
Suddenly, fast food, fried foods, and high carb + high fat foods are out. They’re replaced by higher quality meats and lots of green vegetables.
That means any improvements are due to low carb, right?
- Both protein quality and quantity have dramatically increased
- And both carbohydrates AND fats have decreased
↓ Total Energy = ↑ Protein Energy + ↓↓ Non-Protein Energy
Research has shown that over the long term, there’s no significant difference between any form of energy restriction, as long as protein energy and non-protein energy balance are accounted for.(2)
In other words, if protein intake is adequate and the calorie balance between carbohydrate and fat is accounted for, it generally doesn’t really matter how that balance is achieved.
Some numbers might make this concept easier to grasp.
If two relatively equivalent individuals eat 150g of protein each and require 2000 kcal of carbohydrate + fat to be in energy balance, it doesn’t matter how that 2000 kcal is divided.
It could be carb dominant, or it could be fat dominant.
Either way, if it adds up to 2000 kcal, and all other factors are equal, then there’s no significant difference.
There are three big levers you can pull for energy restriction:
- You can restrict by daily total calories and not pay attention to whether they’re carbohydrate or fat (the classic ‘calorie counting’).
- You can restrict by time, eating your calories inside a narrow window of time, and not eating outside of that window (fasting or time-restricted feeding).
- You can restrict by macro, cutting the majority of either carbohydrates or fats.
But if protein intake is equal, it largely doesn’t matter which lever you pull.
If the restriction equivalent, you would largely achieve the same result in terms of body composition or body weight.
However, remember that you’re a woman athlete. You will see differences in performance, particularly related to strength, power, and high-intensity output.
Advanced Nutrition Tools and Carb Intake
You may have a hard time with the above statement due to your own personal experience.
Each one of the ‘levers’ described above is an example of a tool – an advanced nutrition practice. And each of those tools has pros and cons.
For every person who finds fasting easier than calorie restriction, there will be someone who’s the opposite.
Eating low fat might be better for those with familial hypercholesterolemia. Low carb or fasting might be better for those with insulin resistance or issues with blood sugar levels.
Counting calories might be better for navigating social situations, where you don’t want to be the odd one out.
Finding an advanced nutrition technique that works for you doesn’t automatically mean it will work for everyone.
Similarly, take a pause before jumping into a very low carb diet plan from a 20-something male personal trainer.
Advanced nutrition practices should be applied once there’s a solid foundation of basics done right and consistently.
Your foundation should include things like:
- adequate protein energy
- avoiding big within-day energy deficits
- having strong systems and structures for for repeating good habits
Put another way, if your food habits are chaotic, work on the basics first.
Pulling one of the levers, or worse, combining them (e.g., combining fasting with carb restriction) in the context of athletic training and a chaotic foundation is bad news.
Often, it means struggling with low energy levels and metabolic compensations which are now working against your initial goals.
In controlled research settings, each of the levers listed above might have good efficacy. They will do what they are supposed to do – in those controlled settings – where all the variables are accounted for and well-managed.
But in the real world, efficacy is not the same as effectiveness.
What is effective for you in your life context, and what is effective for someone else in their life context can be quite different.
And yet, in nutrition arguments and debates, people argue the efficacy of one nutrition strategy over another, when what they’re actually arguing about is the effectiveness of a strategy they’ve tried in their context.
Drawbacks of Low Carbohydrates for Women Athletes
There are multiple effective strategies for achieving a variety of outcomes in nutrition. This is especially true when protein energy and non-protein energy are equal between each.
There are also many ineffective nutrition strategies.
And these are the ones I see when active women come to me for help.
Unfortunately, many of these women athletes find the strategies work for a while. But then, those strategies stop working.
Everything in nutrition works right up until it doesn’t.
Because so many women use advanced nutrition practices before getting the fundamentals in order, it only a matter of time before the house of cards comes crashing down.
Again, here’s the repeating pattern I see in the athletic women over 40:
- You’re not eating enough total protein energy to start with. The daily distribution and quality of this protein needs improvement.
- In an attempt to accelerate weight/fat loss, you’ve cut your total carbohydrate intake. At the same time, you’re trying to keep up with vigorous training that mostly requires carbohydrate as the primary fuel.
↓ Total Energy = ↓ Protein Energy + ↓ Non-Protein Energy
What tends to happen to both weight and body fat levels, in the short term, when all forms of energy across the board are cut?
Effective in the short term. Ineffective in the medium to long term.
And, crucially, once this strategy becomes ineffective, it rarely becomes effective again.
Or at least, the period of effectiveness shrinks and your body becomes increasingly resistant to further attempts to make that strategy work again.
Eventually nothing will budge and you end up frustrated.
What About Low Carb Intake, High Fat?
Since you’re an astute reader, you may have picked up on something.
AsI I’ve already stated, if protein energy is sufficient, it doesn’t matter much how the non-protein energy side of the equation is balanced.
In theory, this means you could follow a low carbohydrate diet – if the remaining non-protein energy is balanced by dietary fat.
Let’s say you require 2400 kcal per day of total energy to cover your basic bodily needs, workouts, and life activities.
And let’s also assume you need 150g of protein per day. This accounts for 600 kcal.
Therefore, your non-protein energy requirement would be 1800 daily calories.
Let’s say you decide to go very low carb at 50g of carbohydrate per day*. This is 200 kcal of energy.
To maintain your energy balance and to not end up in a large energy deficit and thus a low energy availability state, you’d have to eat 1600 kcal of fat per day.
This is a fraction under 180g of fat per day.
For reference, that’s equivalent to 15 tablespoons of olive oil.
Even if you opted for a more moderate (relatively) carbohydrate intake of 150g per day (600 kcal), you would still require over 130g of dietary fat to remain in energy balance.
I often see some women eat relatively close to the above carbohydrate and fat intakes. So why do they still run into issues?
Usually, it’s because that fat intake results in a dilution of protein. Fattier cuts of meat, high fat dairy, sauces, nut butters, etc., are displacing protein energy and creating a relative protein energy deficit.
It feels like you are eating high protein foods, but you are actually eating high fat foods containing some, but often not enough, protein.
If you eat more of these foods to hit your protein energy target, your fat intake tends to go through the roof.
Remember that provided protein energy is sufficient, it doesn’t matter how the non-protein energy side of the equation is balanced. If you’re eating a high fat, protein dilute diet, your protein energy won’t be sufficient.
*I’m using this as an example, not something I suggest you actually do.
What is Gluconeogenesis?
Making the numbers balance is one thing. But remember, you eat food, not numbers.
While restricting carbohydrate-dense foods is relatively easy for many women, in my experience, it’s often more difficult to get them to eat enough protein.
What I haven’t yet made clear in my example from above is that when following a low carbohydrate diet, some extra protein is needed to provide sufficient additional amino acids for gluconeogenesis.
Gluconeogenesis (3) is the process by which the body can meet the minimum glucose requirements of certain organs and cells in the body – brain, kidney, and red blood cells.
It does this through the conversion of specific amino acids to glucose metabolites. These can be fed into glucose metabolism pathways.
Without this additional amino acid supply, some from what is eaten will still be diverted, preferentially, to energy metabolism.
This means less is available for recovery, repair, muscle building, and other functions in the body. Insufficient protein energy means progressive lean tissue loss over time, especially muscle.
Let’s say 150g of protein is required per day at baseline.
Then, on a low carbohydrate intake diet, a woman might require an additional 30 grams or so to allow for up-regulated gluconeogenesis. This makes getting enough protein intake an even greater challenge.
But even when this level of protein intake is possible, the above example also requires a significant amount of fat to be consumed.
Some fatty acids can be converted to ketones, providing an alternative fuel source for some of the tissues normally preferring glucose as their primary fuel. And glycerol, from fats, can also be fed into gluconeogenic pathways.
Is High Fat Practical for High Intensity Athletes?
In my experience, few women successfully eat both high protein and high fat consistently.
To hit this kind of fat intake, even from healthy fats, you’re looking at a lot of Greek yogurt, avocado, nut butters, oils, and fattier cuts of meat.
Whether it be taste, texture, mouthfeel, or digestibility, many athletic women don’t seem tolerate a large amount of very high-fat foods.
A quick calculation to get to 150g of fat (from relatively low carbohydrate foods) would look something like eating all of this in one day:
- 300g of Greek yogurt
- 4 tablespoons peanut butter
- 1 whole avocado
- 3 tablespoons olive oil
- 4 rashers bacon
Okay for a Sunday brunch every now and then, but we are talking about eating this way every day. And the above is relatively protein dilute, so we still need to factor that in.
Could it be done? Yes. And there are some women who might do this every day.
Do I see the majority of athletic women being able to eat this way? No.
Social media is brimming with young men, who can eat very large amounts of food, hit those targets and potentially make it work for them. However, I just don’t see this happening in many women.
So while this approach has efficacy, in theory, it simply isn’t effective in real world practice.
Let’s put a point on this before moving on:
If it’s very difficult for a woman athletic to consistently fuel her energy requirements using a low carb, high fat approach (remember, fat isn’t a significant fuel during strength training and high intensity exercise)…
And if the goal is to NOT to under-eat and fall into a low energy state, then you need to find a better balance on the non-protein energy side of the equation.
This means increasing carbohydrate intake, with the added benefit that it is a much better fuel source for strength training and high intensity conditioning work.
Nutrition Versus Fueling – What’s the Difference?
Okay, for someone who started out saying they didn’t even want to write on this topic, I sure have said a lot. Well done for making it this far.
What’s the key takeaway?
You have got to fuel your pursuits.
My focus and passion is in the tagline for this website: fuel your strength. Active women like you deserve to feel energetic and strong.
But this approach means understanding of the difference between nutrition and fueling.
On the daily, I have women reaching out to me frustrated that the wheels are falling off their health and performance with the nutrition and fueling strategies they have been following.
Commonly, this has involved significantly limiting carbohydrates in one form or another.
Nutrition (or diet, noun) is what you do everyday for your health and wellbeing.
- eating a good minimum level of high-quality protein
- eating a wide variety of plant foods, including the high fiber veggies and legumes
- basing the majority of your diet around whole and less processed foods
- staying well hydrated
- having the structures and systems in place to allow you to do this consistently most days (planning, preparing, eating regularly, etc).
The sum total of this should form a strong foundation to your everyday nutrition. This will also include a minimum grams of carbs per day (130 grams of carbohydrates).
Fueling is what you ADD to the above based on your specific needs and context. For example, an Ironman triathlete will fuel herself differently than a hard charging recreational CrossFit athlete.
My focus, over several articles now, has been to reinforce the notion that women athletes like you need to eat.
You need to fuel yourself well to build a robust metabolism and strong body.
Under-eating is under-eating, no matter how you slice and dice it.
Active women in particular really need to reject the pervasive belief that carbohydrates are bad.
In the context of fueling your strength and high-intensity conditioning work, you need enough carbs – particularly in the form of complex carbohydrates – to fuel your activity.
Amounts and Timing of Carbs
The conversation about carbohydrates for women athletes isn’t complete with this one article. There’s more to cover and I’m sure you’re curious about details.
Common questions I get include:
- What’s about complex carbs versus simple carbs or added sugars?
- Do I need more starchy veggies like sweet potatoes or whole grains such as brown rice?
- Do carbs without fiber, such as fruit juice, have a place?
- Should I eat carbs before or after a workout?
- What amount of carbs do I need for the kind of workouts I do?
Stay tuned because in the next article, I’ll tackle amounts, types, and timing of carbohydrate intake for strength training.
Summary of Carbohydrates for Women Athletes
The importance of carbohydrates to women athletes is an important – and to some people – a controversial topic.
This article provided context and a conceptual understanding of:
- Why, for female athletes who train with intensity, carbohydrates are a key fuel. Carbs should not be feared.
- Carbohydrates, along with fats, make up the non-protein energy piece of your energy needs.
- A low carb approach may be effective for certain populations. However, in busy, active women who train with intensity, it’s often not the most efficacious way to fuel.
- Carbohydrate intake for women athletes should be looked at in terms of fueling, not just general nutrition.
- Future articles will cover the practical application of these carbohydrates for women athletes concepts.
2 Gardner CD, Trepanowski JF, Del Gobbo LC, Hauser ME, Rigdon J, Ioannidis JPA, Desai M, King AC. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial. JAMA. 2018 Feb 20;319(7):667-679. doi: 10.1001/jama.2018.0245. Erratum in: JAMA. 2018 Apr 3;319(13):1386. Erratum in: JAMA. 2018 Apr 24;319(16):1728. PMID: 29466592; PMCID: PMC5839290.