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COOL THINGS YOU MAY NOT KNOW ABOUT CARBS
1. CARBS ARE ONE OF YOUR 3 MACRONUTRIENTS
Carbohydrate is one of the three main macronutrients alongside protein and fat.
They’re broken down into smaller molecules, including glucose, which cells can use to produce energy.
2. YOUR BRAIN HAS A BIG DEMAND FOR GLUCOSE 🧠
The brain normally relies heavily on glucose for energy.
It cannot store significant amounts of glucose itself, so it depends on a continuous supply from the blood.
That’s one reason inadequate carbohydrate and overall energy availability can affect things like concentration, decision-making and cognitive performance.
3. CARBS ARE PARTICULARLY IMPORTANT FOR HIGH-INTENSITY EXERCISE ⚡️
As exercise intensity increases, carbohydrate becomes increasingly important as a fuel source.
Why?
Because carbohydrate can be metabolised to produce ATP — the energy currency of cells — at a faster rate than fat oxidation can provide energy during very intense exercise.
Think:
sprints → intervals → hills → hard racing → finishing kicks.
4. YOUR BODY STORES CARBS AS GLYCOGEN 🔋
Carbohydrate is stored mainly as glycogen in your muscles and liver.
Your muscles use their glycogen stores locally during exercise, while liver glycogen helps maintain blood glucose.
That makes glycogen one of your body's key readily available carbohydrate fuel reserves.
5. GLYCOGEN IS STORED WITH WATER 💧
A commonly used estimate is that each gram of glycogen is stored with roughly 3 g of water.
So when someone dramatically reduces carbohydrate intake and sees the scales fall rapidly at first, much of that initial change can be water associated with depleted glycogen, rather than equivalent fat loss.
6. FIBRE IS A CARBOHYDRATE 🌱
Dietary fibre is technically carbohydrate, but much of it isn't digested and absorbed as glucose in the small intestine.
Different fibres can support:
- bowel regularity
- gut microbiota
- satiety
- blood-glucose regulation
- gastrointestinal health
UK guidance recommends around 30 g of fibre per day for adults.
7. YOUR GUT BACTERIA CAN USE SOME CARBS 🦠
Certain fibres and resistant starches reach the large intestine, where gut microbes ferment them.
This produces short-chain fatty acids, including acetate, propionate and butyrate, which have important roles in gut and metabolic health.
So some carbohydrates are essentially food for your gut microbes.
8. CARBS CAN HELP WITH HYDRATION 💧
Carbohydrate and sodium can work alongside intestinal transport mechanisms to promote fluid absorption.
This is one reason carbohydrate-electrolyte drinks can be useful during prolonged exercise.
9. CARBS HELP REPLENISH GLYCOGEN AFTER TRAINING 🔄
After exercise, carbohydrate helps restore muscle glycogen.
For rapid recovery when another demanding session is coming soon, sports nutrition guidance commonly recommends around 1.0–1.2 g carbohydrate/kg/hour during the first 4 hours after exercise.
So recovery fuelling isn't just about protein.
10. ENDURANCE ATHLETES CAN NEED A LOT OF CARBS
For athletes, carbohydrate recommendations are often expressed relative to body weight and training load:
~3–5 g/kg/day → light training
~5–7 g/kg/day → moderate training
~6–10 g/kg/day → heavy training
~8–12 g/kg/day → very high/extreme training loads
The exact requirement depends on the individual, training and total energy needs.
A marathon block is not the same fuel demand as a rest day.
11. DURING LONGER EXERCISE, 30–60 G/H IS A COMMON RANGE
For prolonged endurance exercise, 30–60 g carbohydrate/hour is a commonly used target.
For longer events, particularly ultra-endurance events, experienced athletes may use up to ~90 g/hour when appropriately trained to tolerate it.
That's something you practise in training, not suddenly attempt on race day.
12. YOUR GUT CAN ADAPT TO CARBOHYDRATE 👀
Regularly practising carbohydrate intake during exercise can improve an athlete's ability to consume and tolerate higher carbohydrate intakes.
That's another reason:
“Train your fuelling”
is just as important as training your legs.
13. GLUCOSE + FRUCTOSE CAN ALLOW MORE CARB TO BE USED
Glucose and fructose use different intestinal transporters.
Combining multiple transportable carbohydrates can therefore increase carbohydrate absorption and oxidation compared with relying on glucose alone.
This is one reason modern endurance fuelling can reach ~90 g/hour in some athletes.
14. CARBS COME IN 3 BROAD FORMS
SUGARS
Fruit, milk, honey and added sugars.
STARCHES
Potatoes, rice, bread, pasta, cassava and plantain.
FIBRE
Legumes, seeds, wholegrains, fruit and vegetables.
They're all carbohydrates — but they behave very differently.
15. “SIMPLE” DOESN'T MEAN “BAD”
“Simple” and “complex” describe aspects of carbohydrate structure.
They don't automatically tell you whether a food is healthy or unhealthy.
A banana and a sweet can both contain sugars, but they're obviously very different foods nutritionally.
Context matters.
16. CARB DIVERSITY MATTERS 🌈
Different carbohydrate sources provide different combinations of:
starch + sugars + fibre + vitamins + minerals + phytochemicals.
So eating a variety of carbohydrate-containing foods can help increase overall dietary diversity.
17. CARBS HELP SPARE PROTEIN 💪
When carbohydrate and overall energy availability are sufficient, carbohydrate can provide energy for exercise and other bodily functions, helping reduce the need to use amino acids as an energy source.
That allows dietary protein to focus on its many other roles, including tissue repair and muscle protein synthesis.
18. CARBS CAN SUPPORT IMMUNE FUNCTION 🛡️
During prolonged or intense exercise, adequate carbohydrate availability can reduce some markers of physiological stress and may help support aspects of immune function.
This is particularly relevant during heavy training blocks and endurance events.
19. CARBS DON'T MAGICALLY BECOME “BAD” AT NIGHT 🌙
There is no physiological switch at 6pm that changes what carbohydrate is.
Your body processes carbohydrate regardless of whether you eat it at 8am or 8pm.
Overall energy intake, dietary pattern and individual needs matter much more than simply the clock.
20. LOW-CARB CAN CAUSE RAPID INITIAL WEIGHT LOSS — BUT…
Reducing carbohydrate can reduce glycogen stores.
Because glycogen is stored with water, this can cause rapid fluid loss.
That early drop on the scales therefore shouldn't automatically be interpreted as rapid fat loss.
21. CARBOHYDRATE AVAILABILITY MATTERS FOR RED-S
This is particularly important for athletes.
Low carbohydrate availability can contribute to low energy availability, particularly when overall energy intake is insufficient to meet the demands of exercise and normal physiological function.
Chronic low energy availability is associated with Relative Energy Deficiency in Sport (RED-S) and can affect multiple body systems, including bone health, reproductive function, immunity, metabolism, cardiovascular health and performance.
So RED-S isn't simply about body weight.
22. CARB FLEXIBILITY ≠ CARB RESTRICTION
Carbohydrate flexibility is about being able to adjust carbohydrate availability according to training demand.
It's not:
“How little carbohydrate can I get away with?”
It's:
“What does my body need for what I'm asking it to do?”
23. YOU DON'T HAVE TO EARN CARBS ❤️
Your body requires energy on rest days too.
Recovery is an active physiological process involving tissue repair, glycogen restoration, immune function and adaptation.
So carbohydrate isn't something you only “deserve” after exercise.
24. AND THE BIG ONE…
CARBS AREN'T JUST FUEL FOR YOUR RUN.
They're involved in:
🧠 brain function
⚡️ high-intensity exercise
🔋 glycogen storage
🔄 recovery
🌱 fibre & gut health
💧 fluid absorption
💪 protein sparing
🛡️ immune function
🍽️ satiety
🌈 dietary diversity
CARBS DO A LOT MORE THAN WE GIVE THEM CREDIT FOR.
REAL FOOD. REAL CARBS. REAL FUEL.
FUEL WITHOUT FEAR. ❤️
