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Exercise And The Female Body: What To Know When You Start Working Out

Exercise And The Female Body: What To Know When You Start Working Out

The female body has specific requirements when it comes to energy and eating when you start working out, so we asked a sports nutritionist for her expert advice.

Getting regular exercise is hot currency nowadays, and it’s not surprising. Science shows that low-, moderate- and high-intensity exercise can all help prevent disease and sustain health. It’s even linked to better diversity in your gut microbiome, which is an important marker for health.

You can find lots of health news and studies encouraging you to get on that bike, walk to work, join a Park Run on Sunday with Dr. Rangan Chatterjee… Your DNA Test recommendations will also encourage you to get moving as part of those changes to optimise your health.

When you do cardio, you burn energy that needs replenishing. If you choose strength training like HIIT, crossfit, or weights, you’ll build muscle by tearing muscle fibers to be healed and reinforced by your body’s natural processes.

So today, we want to talk about nutrition when you start working out, because eating right is a critical aspect of being active. In particular, we’re going to talk about the specific needs of the female body when sport is added to the weekly activity mix.

The reason we’re focusing on women is because, at Atlas Biomed, we deal in the details and we like to be precise. Even a general article on how to eat when you start sports would completely overlook the significant differences between the male and female body.

These differences affect how the body responds to exercise, fat metabolism, muscle recovery, and even essential nutrient levels. For women, sports without the right nutrition can cause hormonal imbalances, low energy levels, issues with bone density, and menstrual cycle problems.

Fortunately for us, our offices are stacked with experts in very specific fields. So we consulted Stephanie Beecroft, a qualified sports nutritionist and personal trainer who works at Atlas Biomed, on why nutrition matters when you start exercising, and how to eat for the active female body.

What you'll learn

The female body, endurance and fat metabolism
Physical stress and hormone imbalances
Unique health risks for female athletes

Fuel your body for cardio

Biological sex preprograms the body for specific characteristics, and this influences athletic performance.

When it comes to men and women, our lungs and hearts are not the same size. We store fat differently and our muscles respond differently to intense exercise.

Most noticeably, we don’t have the same reproductive organs, and they are run by different hormones. We also have different needs when it comes to nutrition.

As it happens, the female body is particularly well adapted to endurance sports and cardiovascular exercise because it’s able to mobilise fat stores and turn them into energy to churn out long-distance activities.

And while that’s an amazing gift of nature, this natural predisposition means that women may overdo the cardio training without noticing that they are underperforming in their nutrition.

This has consequences for the body, but also on how sustainable your exercise program is. It might even make you quit.

The Gym Arrow
Photo by George Pagan III / Unsplash

What our expert says

Women respond to exercise differently to men: women have a greater capacity to utilise and transport fats, which is handy for us when it comes to endurance style running as our bodies are designed to help us keep going.

Because our bodies are designed for fat burning, we have better oxidation rates than men. This means we are better able to handle lactic acid build-up (that's why muscles hurt after a workout), so we can push through that discomfort, and, in essence, exercise harder.

Women are naturally better designed for endurance exercise, which is why we are so much better at pushing hard and overtraining whilst eating very little.

But this can lead to burn-outs, no energy and low morale, quitting your heavy training regime, putting the weight back on, and then repeating the cycle.

For weight loss, consider swapping one of your cardio workouts to a weight session to help build lean muscle and burn more calories. This can be low impact and less stressful on your body.

☝️SOLVE IT☝️ The key to optimal health when training (for weight loss, sports, or an upcoming special event) is having a balanced diet: carbs, fats, and proteins are all important. Don’t make drastic changes to your diet when starting a new training regime: too much change for the body to handle and you will end up burnt out or sick.

Training causes stress

Exercise naturally induces biological stress that allows the body to adapt and conquer strenuous challenges, but too much can throw the whole system out of whack.

It’s not just bad bosses, noisy neighbours, and nosy parents that make our lives stressful, exercise can too. This type of stress doesn’t necessarily play out in your brain, but it triggers a cascade of events in your body.

Indeed, if you’ve trained your body to lounge and binge-watch excellent TV shows (no judgement, we’ve all done it), then your cardiovascular system isn’t primed for effort, nor are your muscles.

So your brain has made the decision to exercise, but your body will understandably be a bit traumatised if you suddenly launch into an extreme program of sunrise jogging and after-work HIIT sessions.

This is the type of stress we’re talking about. Shocked, your body reacts to the intense effort by producing stress hormones that screw with a lot of important natural functions.

This is because the body uses pregnenolone to make hormones, and when it’s stressed, it prioritises the production of cortisol, the stress hormone, over other ones. This can be compounded by undereating, especially if you're trying to lose weight.

What our expert says

Training adds stress to the body. Increased stress immediately triggers the release of several hormones: testosterone, DHEA, and cortisol. Not managing your blood sugar levels properly also causes stress on the body.

If you overexercise and undereat, your endocrine system (that makes hormones) goes through a process called the pregnenolone steal. It allows your body to continue producing cortisol (which can also be the cause of PMS), but it lowers the production of important female hormones (progesterone and oestrogen), leaving you with hormonal imbalances.

When stress is low, thyroid function is better, and the body produces hormones that work in symbiosis: growth hormone, melatonin, oestrogen, and progesterone. Being stressed is also one of the main killers of your healthy gut microbiome.

☝️SOLVE IT☝️ One way to keep your hormones in check is to stress less! This means training and eating sensibly based on your energy output. Keeping tabs on your gut microbiome health is also an excellent way to determine whether your training schedule is having a negative impact on your health.

Is this the reason you gave up last time?

Female athletes are prone to energy and iron deficiencies that affect wellbeing, mental resilience, and bone density. It can even switch off menstruation.

Energy deficiency Menstrual problems Weak bones

There are a few biological truths that define our existence as sentient beings - they also differentiate us from plants and minerals. As living, breathing creatures, we require energy to fuel our existence. Contrary to plants, man cannot survive on oxygen alone.

Our bodies need energy, and that comes from our diet. We also need nutrients from the food we eat because we are made up of impressive nanomachinery that can transform elements in nature into important substances.

Photo by Chase Kinney / Unsplash

Things like vitamins, minerals, and amino acids oil our mechanics, maintain bone and muscle, and make up the tissues of our organs. So when you demand more of your body, you need more energy and nutrients.

The female body has specific requirements because it’s designed to bear children - not fertilise the seed. But, because the female body has been engineered for this reproductive feat, it has an impact on the body’s functions and needs.

Getting into sports is an excellent way to remind the body of its roots - after all, we did once spend our days scavenging, hunting, and avoiding predators.

However, women have unique issues when it comes to nutrition and deficiencies as a result of exercise. It’s called the female athlete triad. It’s a very common problem and disordered eating can be part of the issue.

What our expert says

The female athlete triad is a combination of energy deficiency, menstrual disturbances, and low bone mass. It can mean more injuries and more time out, which can have a physical and psychological impact on the athlete and their performance.

Energy deficiency: constant tiredness, low morale, no drive, anxiety, and poor mood are all symptoms which you need to pay attention to. Female athletes are more likely to become deficient in iron also, especially if they follow a vegan, vegetarian, or low-red meat diet.

Menstrual disturbance caused by excessive stress on the body can lead to fewer or no periods. If this problem happens over a long period, it may eventually compromise your fertility.

Low bone mass is not only a risk for older women. Prolonged intense physical effort can cause stress fractures and loss of bone density (osteopenia).

☝️SOLVE IT☝️ It might simply be that you are not fuelling yourself correctly to support your training, so remember to eat balanced meals with carbs, protein, and fats that contain enough energy to compensate your body for the effort. If you are concerned about your iron levels, get them checked or add a moderate amount of red meat and offal to your diet.

The final word

Stephanie shares some final important advice to start exercising in a sustainable way, and avoid common mistakes that take the fun out of sports.

To exercise regularly and still feel good while performing at optimal levels, you must ensure you are putting the energy back in which you burn. So track your energy output and input.

Fitness trackers can help monitor how much energy you expend, and food tracking apps can help you figure out if you’re eating enough.

If your goal is to lose weight, don’t put yourself in more than a 500kcal per day deficit (output vs. input) because it will add more stress to your body. Remember, patience is the key to losing weight and keeping it off long term.

If you are not sure about how to fuel yourself properly, find a professional to calculate your BMR (basal metabolic rate) and your total energy requirements for the day. You can also find lots of resources online about how to fuel correctly on training and rest days.


1. The female body is particularly good at fat metabolism and endurance.
2. Your diet should have all macronutrients: carbs, fats, and protein.
3. Too much stress puts your endocrine system and hormones off kilter.
4. Undereating when exercising causes stress and deficiencies.
5. The female body has specific nutritional needs, including iron.
6. When you burn energy exercising, you need to put it back in.
7. Make a plan for working out and eating for optimal energy levels.

Leigh Stewart
Leigh Stewart Head of Atlas Biomed content, trained chef and avid fermenter of edible bacteria.
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