What Is RED-S? (Relative Energy Deficiency In Sport)

You may have heard of the acronym RED-S in the sports-world, but what is RED-S to be exact? And can it affect men as well as women? I'm going to explain everything you need to know, what the signs and symptoms to look out for are, and how to start your rehabilitation to get back to a stronger, better you.

What is RED-S?

Relative Energy Deficiency In Sport occurs when caloric intake (food = energy in) does not meet training demands and essential bodily functions (expenditure = energy out).

RED-S does not occur from short-term caloric deficits. It develops from consistenly under-fuelling over time, causing hormone, health, performance and recovery issues.

Can men have RED-S too?

Low energy availability is usually linked to women due to diet culture and years of caloric restriction. RED-S was once known as "The Female Athlete Triad" due to it being a primary cause for amenorrhea.

However, men are most definitely affected by RED-S too. I honestly can't tell you how many male competitive athletes and training enthusiasts I have worked with on rehabilitation over the years. Most symptoms for men are the same as women, including extreme fatigue (or feeling "tired-but-wired" - more on that later), poor bone health and performance drops to name a few. But the most common issue is low testosterone, causing libido. to absolutely tank. Bad times, eh?

Who Is Affected By RED-S?

RED-S does not just affect elite athletes. Recreational athletes and training enthusiasts get RED-S too. It occurs within endurance sports, strength sports, weight-class-governed sport and even physique prep.

And trust me, single-digit body-fat percentage is not a precursor for RED-S. RED-S can affect all body sizes because it's not caused by a set weight or body-fat percentage. It's about low energy availability impacting metabolism, digestion, hormones and increasing cortisol. In this state the body breaks down muscle for fuel.

How Does Under-Fuelling Cause RED-S?

Because of the above, someone may look at their reflection in the mirror and reason, "I'm not that lean, I have lots of body fat to lose" so I should push harder. So, the under fuelling occurs intentionally due to over-restriction of caloric intake to change body composition, and, as a results of eating disorders and fear of weight gain (...if I had a £1 for every man and woman who has come to me out of a physique prep with this mindset...!).

However, RED-S can also occur from mistakenly underestimating caloric and macro needs. Let me explain.

Marketing and diet culture champions protein as the king of all gains. "Protein is the building block of every cell of the body". "AMINO ACIDS!" So, people mistakenly think that eating high protein means they can’t have RED-S. That surely, their body has all the good stuff it needs for recovery from intense training.

But consider this; high protein diets are sating, sometimes contributing to under eating (due to feelings of fullness) overall calories and missing out on enough of the other macronutrients (carbohydrates and fats). Over eating protein can result in masking low energy availability.

While protein is essential, most athletes already meet evidence-based requirements (1.6-2.2g/kg/day). Excess protein displaces carbohydrates resulting in reduced muscle glycogen, impaired training adaptation, increased cortisol and immune stress, lower iron absorption (remember that physically active people have a higher turnover of iron than general population, and iron helps the body metabolise protein... so no over-eating of protein is going to help if the body can't actually utilise it due to low iron!). So, although the message to eat high protein is rooted in real physiology, it's been taken out of context and sometimes used at the expense of adequate energy and carbohydrate intake.

How Does Over-Training Link With RED-S?

Sport culture normalises fatigue, recovery issues and even amenorrhea.

"The grind" is glorified.

Overtraining creates a severe energy gap where training demands exceed calorie intake, forcing the body to shut down non-essential functions like reproduction (menstrual cycles and libido as mentioned above). RED-S and OTS (Overtraining Syndrome) symptoms heavily overlap (fatigue, poor performance, frequent injuries), the key distinction is that OTS is about training stress, while RED-S is about the energy deficit caused by training stress (and/or under-eating).

I often see the two occur together, particularly in highly-trained individuals who engage in lengthy event and competition preps. Such as back-to-back powerlifting peaks with no recovery and GPP phases between, or no periodisation of marathon and ultra-endurance event programming.

People will go for years trying to improve performance by throwing supplementation at the symptoms, or ignoring them altogether reasoning that what they are experiencing is normal. Some are so desperate for leanness they will pursue it at any cost.

Addressing the energy gap is crucial for recovery from both under-fuelling and over-training. "Push harder" is not the answer.

What Are The Symptoms Of RED-S?

Relative Energy Deficiency In Sport and Over Training Symptoms Include:

• DECREASED PERFORMANCE

• STRENGTH LOSS

• FREQUENT INJURIES

• BONE DENSITY LOSS

• STRESS FRACTURES

• LOW IMMUNITY

• THYROID ISSUES

• ANXIETY

• DEPRESSION

• EXTREME FATIGUE

• SLEEP ISSUES

• HPA AXIS DYSFUNCTION (Adrenals. The hypothalamic-pituitary-adrenal axis regulates the body's stress response. Dysregulation can lead to overactivity or underactivity resulting in fatigue, anxiety, poor stress tolerance, and cognitive issues, and is linked to metabolic, cardiovascular, immune, and mental health disorders. The brain is on high alert from your body's stress response system being stuck in overdrive, releasing stimulants like cortisol and noradrenaline even when you're exhausted, making you feel physically drained but mentally alert and unable to relax or sleep... some desccribe the feeling of "tired-but-wired".

• WEIGHT LOSS

• INCREASED BODY FAT STORAGE

• SUPPRESSED METABOLIC RATE

• WATER RETENTION

• BLOATING

• CONSTIPATION

• DIARRHOEA

• URINARY INCONTINENCE

• DECREASED SEX HORMONES

• MISSED PERIODS

• LOW SEX DRIVE

• ERECTILE DYSFUNCTION

How To Recover From RED-S And OTS

It's a collaborative process. I’ve helped male and female athletes and training enthusiasts recover from RED-S, involving their sports coach because often, training programming needs to be adjusted to determine a reasonable recoverable load.

In tandem, I have created a truly personalised Bespoke Functional Nutrition Programme to ensure that energy demands are being met, using. a framework of well balanced, regular meals. Never training fasted, carbohydrates are prioritised pre, intra and post-training. Digging deeper, nutrient-rich micronutrient-specific foods are. integrated to ensure the right vitamin and mineral intake, before looking at any supplementation is required to close the gap. 1:1 coaching with me ensures consistent progress over time, "tweaking the dials" as needed, closely monitoring all bio-markers and crucially, providing nutritional psychology to alleviate any discomfort through the process.

If any of this article has resonated with you, I'm ready to help rehabilitate you from RED-S and achieve your full potential. Find out how you can work with me.