Fuelling As A Female Athlete: What Your Male Coach Doesn't Understand

As a female triathlon coach who's worked with both male and female athletes, one of my pet peeves is female athletes being given generic sports nutrition advice that was primarily researched on men, by men, for men - and it's not working.

Your male coach might mean well, but here's the thing: women are not just smaller men. Our hormonal fluctuations, metabolic differences, and physiological responses to training and nutrition are fundamentally different. Yet most coaching advice completely ignores this.

Let me break down what your body actually needs - based on the latest research specifically on female athletes.

The Problem with Generic Sports Nutrition

Most sports nutrition research has historically used male subjects. Why? Because women's menstrual cycles were considered "too complicated" and created variables that researchers didn't want to deal with. The result? Nearly everything we thought we knew about sports nutrition was based on male physiology.

This is why finding a female triathlon coach or women's personal trainer who understands these differences is crucial for your performance and health.

Understanding Your Menstrual Cycle

Let's start with the elephant in the room. Your cycle affects everything - your energy needs, carb tolerance, recovery requirements, and even how you respond to different training stimuli. Instead of ignoring this, we need to work with it.

Menstrual & Follicular Phase (Days 1-14):

• Oestrogen is rising, insulin sensitivity is higher

• You tolerate carbs better and recover faster

• This is your time to push harder in training

• Energy needs: standard recommendations work here

Luteal Phase (Days 15-28):

• Progesterone dominates, metabolic rate increases by 5-10%

• You can literally burn 100-300 more calories per day, so you need to eat more (which explains where those cravings come from!)

• Carb tolerance decreases, fat oxidation increases

• Sleep and recovery become more challenging

You need more food in your luteal phase, not less. Yet this is when most women restrict calories because they feel "bloated" or think they're gaining fat (spoiler: it's just water retention before your period starts).

Iron: The Performance Killer No One Talks About

Iron deficiency affects up to 35% of female athletes, even without anaemia (Burden et al., 2015). Yes, you can have "normal" blood work but still be functionally iron deficient, which is known as iron deficiency without anaemia (IDWA).

IDWA happens when your iron stores are depleted and causing symptoms, even though your haemoglobin levels appear normal on standard blood tests. The key indicator you need to be tested for? Ferritin levels - which measure your iron stores, not just circulating iron.

Factors Contributing to Iron Deficiency in Female Athletes

Menstrual Blood Loss: The most obvious factor - women lose iron during each menstrual cycle through blood loss. Athletes with heavy periods (lasting longer than 7 days) are at even higher risk.

Increased Iron Demands from Training:

• Endurance exercise increases iron requirements by up to 70% (Żebrowska et al., 2023)

• Foot-strike haemolysis (breakdown of red blood cells from repetitive impact) in runners (Lippi et al., 2012)

• Increased iron losses through sweat during prolonged training sessions. Athletes can lose 1–2 mg of iron per 2 hours of exercise, with higher losses during very strenuous or prolonged activities (Kapoor et al., 2023)

  
  

Dietary Factors:

• Many female athletes avoid red meat (the best source of haem iron) due to body composition or ethical concerns 

• Plant-based diets, while healthy, contain non-haem iron which is poorly absorbed

• Tannins in tea and coffee (consumed around meal times) significantly reduce iron absorption

• Inadequate calorie intake often means inadequate iron intake. When you're not eating enough overall, you're likely not getting enough iron-rich foods

  
  

Signs of iron deficiency:

• Fatigue that doesn't improve with rest

• Feeling breathless during easy efforts

• Heavy legs during training

• Cold intolerance

• Restless leg syndrome

  
  

Iron deficiency can masquerade as poor fitness, lack of motivation, or overtraining, leading to months of frustrating training with no progress.

Protein Timing That Actually Works for Women

Here's where the research gets really interesting - and what your male coach probably isn't thinking of. Recent studies reveal that men and women have fundamentally different protein metabolism and recovery requirements (Small, 2025).

The Key Differences: women oxidise less protein and leucine (the amino acid that triggers muscle protein synthesis) compared to men, which directly affects how efficiently we recover from exercise. But here's the kicker - our hormonal fluctuations make timing critical:

• Oestrogen can inhibit muscle protein synthesis

• Progesterone can enhance muscle breakdown

• During high hormone phases (when oestrogen peaks), women experience reduced efficiency in muscle protein synthesis

  
  

What This Means for Your Recovery: women need to consume 20-25g of high-quality protein plus 40-60g of carbohydrates within 1 hour post-exercise. Your body needs immediate post-workout nutrition to prevent lean muscle loss - especially during certain phases of your cycle. Meanwhile, men have a leisurely 3-4 hour window for optimal recovery.

Best sources of protein for athletes:

• Greek yoghurt (look for the "strained" varieties for higher protein)

• Eggs (complete amino acid profile)

• Lean meat or fish

• Plant-based: quinoa, tofu, nutritional yeast, pulses, nuts and seeds

The Energy Availability Crisis: LEA and RED-S

Another key issue affecting many female athletes is energy availability. Research from 2023 in the Journal of Sports Sciences found that up to 58% of female endurance athletes show signs of low energy availability (LEA), and many progress to the more serious condition known as Relative Energy Deficiency in Sport (RED-S) (Logue et al., 2020).

Low Energy Availability (LEA) is a condition where there isn't enough energy from a person's diet to support their body's functions and energy expenditure from exercise. Think of it as the fuel tank running low.

Relative Energy Deficiency in Sport (RED-S) is the health and performance impairment that occurs as a consequence of prolonged LEA. In essence, LEA is the cause, and RED-S is the resulting set of harmful physiological and psychological effects on the athlete.

Symptoms of RED-S

• Loss of periods (amenorrhoea)

• Bone density loss leading to stress fractures

• Chronic fatigue

• Irritability and depression

• Compromised immune system leading to frequent illness

• Rapid weight loss

Why Women Are More Vulnerable: The Diet Culture & Body Image Trap

Here's the uncomfortable truth your male coach probably doesn't understand: women are disproportionately affected by LEA and RED-S because we've been conditioned by society to eat less and try to shrink ourselves.

From childhood, girls receive messages that taking up less space and looking slim is desirable. We're praised for being "good" when we eat small portions, skip dessert, or show restraint around food. Meanwhile, boys are encouraged to "eat up" to fuel their growing bodies and athletic pursuits. They're praised for having big appetites and aren't shamed for second helpings. This messaging doesn't magically disappear when we become athletes. If anything, it intensifies.

The pressure on female athletes to be lean whilst performing well creates a perfect storm for disordered eating and poor performance: societal pressure to be small + sport-specific pressure to be lean + generic nutrition advice designed for men = chronic under-fuelling

The truth about female athlete body composition:

• Your body fat percentage will be higher than male athletes (and that's healthy)

• Weight fluctuations throughout your cycle are normal (1-2 kg)

• Performance and appearance goals can conflict (your genetics play a huge factor) - choose performance

• Your worth is not determined by a number on the scales

Your performance will skyrocket when you stop restricting your food

Breaking Free from Diet Culture as an Athlete

The first step in proper fuelling is recognising how deeply diet culture has infiltrated your relationship with food and your body. As a women's triathlon coach and personal trainer, I help my clients identify these patterns:

Ask yourself:

• Do you feel guilty after eating certain foods?

• Do you exercise to "earn" food or "burn off" meals?

• Do you restrict food intake based on how you look rather than how you perform?

• Do you praise yourself for eating less or others for being "disciplined" with food?

These are all diet culture red flags that have nothing to do with athletic performance and everything to do with societal conditioning.

Real Talk: What I Tell My Female Athletes

As a women's personal trainer specialising in triathletes and runners, here's what actually works for my female athletes:

1. Eat for your cycle: more food in the luteal phase, strategic carbs in the follicular phase

2. Get your blood work done: if you suspect you are iron deficient

3. Track your cycle: use it to adapt your training and nutrition

4. Prioritise sleep: women need more recovery time, especially luteal phase

5. Ditch the scales: use performance metrics, how you feel, and progress photos

6. Challenge diet culture thoughts: every time you catch yourself thinking "I shouldn't eat this," ask "Will this fuel my performance?" or "Will this help me recover better?"

   
   

How Male Coaches Can Train Women (The Right Way)

I'm not saying male coaches can't work with female athletes - but they need to:

• Stay updated on female-specific research to understand the differences

• Work with female sports nutritionists

• Listen when their female athlete tells them something doesn't feel right

• Recognise their own unconscious biases around food and female bodies

• Actively challenge diet culture messaging

This is why many female athletes benefit from working with a women's personal trainer or female triathlon coach who inherently understands these challenges.

The Bottom Line

Your body is not broken or complicated - it's designed differently. When you fuel it properly, respect its rhythms, and work with (not against) your physiology, incredible things happen. Trust your body. Fuel it properly. And watch what happens when you finally give it what it actually needs. You don't need to be a smaller version of a male athlete - you need to be the best version of yourself.

Want to learn more about fuelling your body? I work with ambitious women who are ready to stop fighting their physiology and start working with it. As an experienced women's triathlon coach and female personal trainer, I specialise in helping female athletes optimise their nutrition and training.

References

Burden, R.J., Morton, K., Richards, T., Whyte, G.P. and Pedlar, C.R. (2015) 'Is iron treatment beneficial in, iron-deficient but non-anaemic (IDNA) endurance athletes? A systematic review and meta-analysis', British Journal of Sports Medicine, 49(21), pp. 1389-1397.

Lippi, G., Schena, F., Salvagno, G.L., Aloe, R., Banfi, G. and Guidi, G.C. (2012) 'Foot-strike haemolysis after a 60-km ultramarathon', Blood Transfusion, 10(3), pp. 377-383.

Logue, D.M., Madigan, S.M., Melin, A., Delahunt, E., Heinen, M., Donnell, S.J.M. and Corish, C.A. (2020) 'Low energy availability in athletes 2020: An updated narrative review of prevalence, risk, within-day energy balance, knowledge, and impact on sports performance', Nutrients, 12(3), 835.

Kapoor, M.P., Sugita, M., Kawaguchi, M., Timm, D., Kawamura, A., Abe, A. and Okubo, T. (2023) 'Influence of iron supplementation on fatigue, mood states and sweating profiles of healthy non-anemic athletes during a training exercise: A double-blind, randomized, placebo-controlled, parallel-group study', Contemporary Clinical Trials Communications, 32, 101084.

Small, C. (2025) 'Optimal protein timing after exercise', Pure Sports Medicine. Available at: https://puresportsmed.com/blog/posts/optimal-protein-timing-after-exercise/ (Accessed: 25 September 2025).