The Complete CrossFit Fuelling Guide: How to Fuel Strength, Power and Performance
CrossFit is one of the most demanding styles of training because it combines multiple physical qualities at once.
A single CrossFit session can involve heavy strength movements, Olympic lifting, gymnastics, conditioning, running, rowing and high-intensity workouts performed under fatigue.
You are not only training muscles.
You are training your ability to produce force, maintain intensity and recover quickly.
That requires more than a good programme.
It requires enough fuel.
You can track your lifts.
You can follow your training plan.
You can push yourself every session.
But without enough energy available, your body cannot fully support the work you are asking it to do.
Fuelling is not separate from training.
Fuelling is part of training.
Why CrossFit Athletes Need Carbohydrates
Carbohydrates are the body’s preferred fuel source for high-intensity exercise.
When you eat carbohydrates, your body stores some of this energy as glycogen in your muscles and liver. During demanding workouts, glycogen helps provide energy for repeated efforts.
This is especially important for CrossFit because workouts rely heavily on high-output movements.
Think about:
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Heavy cleans
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Snatches
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Squats
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Thrusters
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Box jumps
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Burpees
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Kettlebell swings
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High-repetition metcons
These movements require energy quickly.
Carbohydrates help support:
✓ Power output
✓ Strength performance
✓ Repeated efforts
✓ Training intensity
✓ Concentration
✓ Recovery between sessions
Many athletes associate carbohydrates mainly with endurance sports.
However, strength and conditioning athletes need carbohydrates too.
A short, intense WOD can place significant demands on carbohydrate stores because the body relies heavily on glycogen during high-intensity exercise.
The goal is not simply finishing the workout.
The goal is performing the workout well and recovering ready for the next one.
Protein Builds Muscle. Carbohydrates Fuel the Training.
Protein is often the main focus for strength athletes.
And protein is important.
It provides amino acids needed for muscle repair and adaptation.
However, carbohydrates have a different role.
Carbohydrates provide the energy needed to:
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Train hard enough to create an adaptation
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Maintain workout quality
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Replace glycogen after training
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Support recovery between sessions
Building strength does not only happen after training.
It starts with having enough energy to perform the training stimulus.
The strongest athletes do not just focus on recovery.
They fuel the work that creates progress.
The Hidden Problem: CrossFit Athletes Can Accidentally Underfuel
CrossFit athletes are often highly motivated.
They train consistently.
They challenge themselves.
They want to improve.
However, as training volume increases, it is easy for fuelling needs to increase without an athlete noticing.
An athlete may add:
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More CrossFit classes
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Extra strength sessions
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Conditioning workouts
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Competition preparation
But their food intake stays the same.
The result?
Their body is being asked to do more while receiving the same amount of energy.
Underfuelling is not always intentional.
Many athletes simply underestimate how much energy their training requires.
Common reasons athletes unintentionally underfuel include:
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Busy schedules
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Not planning meals around training
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Fear of carbohydrates
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Prioritising protein while reducing carbs
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Training early without eating
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Struggling to eat after intense sessions
Why You Might Struggle to Eat After a Hard WOD
One of the most common challenges for CrossFit athletes is knowing they need recovery fuel but struggling to eat afterwards.
After a demanding session, some athletes experience:
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Reduced appetite
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Nausea
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Feeling too tired to prepare food
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An unsettled stomach
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Feeling full despite needing fuel
This can happen because intense exercise temporarily changes digestion.
During hard training:
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Blood flow is prioritised towards working muscles
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Stress hormones increase
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Digestion can slow temporarily
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Heat and exertion can reduce appetite
This can create a cycle:
Hard workout → reduced appetite → missed recovery fuel → lower energy for the next session
For athletes training several times per week, consistently missing recovery nutrition can affect training quality over time.
Recovery does not always need to start with a large meal.
Sometimes it starts with something convenient and easy to consume.
Low Energy Availability (LEA) and RED-S in CrossFit
Low Energy Availability (LEA) occurs when the energy available after exercise is not enough to support normal body functions.
Your body needs energy for more than training.
It also requires energy for:
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Recovery
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Hormonal function
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Bone maintenance
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Immune health
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Metabolism
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Everyday activity
When energy availability remains too low, the body may struggle to support all these processes.
This is where Relative Energy Deficiency in Sport (RED-S) becomes important.
RED-S is not only an endurance athlete issue.
It can affect athletes in strength and conditioning environments too.
Any athlete training hard without enough energy can be at risk.
How Underfuelling Can Affect CrossFit Performance
Many athletes think underfuelling only affects body weight.
However, performance changes can appear first.
Athletes may experience:
Reduced workout quality
Including:
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Lower power output
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Faster fatigue
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Difficulty maintaining intensity
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Workouts feeling harder than expected
Poor recovery
Training creates stress on the body.
Fuel allows the body to repair and adapt.
Without enough energy, athletes may experience:
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Longer recovery times
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Persistent soreness
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Reduced readiness for the next session
Increased injury concerns
The body needs energy to maintain and repair:
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Muscles
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Tendons
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Ligaments
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Bones
Chronic low energy availability is associated with concerns around bone health and stress injuries.
Training creates the stimulus.
Fuel allows adaptation.
Underfuelling: The Numbers
Underfuelling is more common than many athletes realise.
A systematic review and meta-analysis involving 6,118 athletes found that 44.7% of athletes across 46 studies were identified as having low energy availability.
The review found:
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44.2% of female athletes showed LEA
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49.4% of male athletes showed LEA
Low energy availability has been associated with:
✓ Reduced performance
✓ Reduced explosive power
✓ Reduced concentration
✓ Reduced coordination
✓ Increased illness risk
The International Olympic Committee recognises RED-S as affecting multiple areas of athlete health, including bone health, hormonal function, immune function, metabolism and performance.
The message is simple:
Your body needs enough energy to support the training you are asking it to do.
Why RED-Scue Uses Cassava and Plantain
RED-Scue was created for athletes who want practical carbohydrate fuel that fits around real training.
Our Energy Bars use cassava and plantain as the main carbohydrate sources.
These are traditional carbohydrate staples used around the world.
Cassava
Cassava is a naturally carbohydrate-rich root.
For athletes, cassava provides:
✓ A carbohydrate source to support energy needs
✓ Starch to contribute towards glycogen replenishment
✓ A practical alternative to traditional sports snacks
Plantain
Plantain is another carbohydrate-rich staple.
For athletes, plantain provides:
✓ Carbohydrates to support high-intensity exercise
✓ A whole-food carbohydrate option
✓ Variety within a fuelling routine
Athletes do not need to fear carbohydrates.
They need enough carbohydrate to match their training.
Your CrossFit Fuelling Strategy: What To Eat and When
The best fuelling choice depends on:
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When you train
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How demanding the session is
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How much time you have before training
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Whether you need fuel before, during or after
A simple way to think about RED-Scue:
Breakfast Fuelling Jar = bigger carbohydrate fuel when you have time to digest.
Energy Bar = flexible carbohydrate fuel around training.
Before Training: Start With Energy Available
Going into a workout already low on fuel can make a hard session feel even harder.
The goal before training is to provide carbohydrate that your body can use.
Around 2 Hours Before Training
Vanilla Breakfast Fuelling Jar
65 g carbohydrates per 120 ml jar
Best for:
✓ Early morning CrossFit
✓ Heavy strength sessions
✓ Longer workouts
✓ Higher-volume training days
Vanilla is designed as a breakfast-style carbohydrate option when you need a larger fuel source before training.
30–60 Minutes Before Training
When you need something closer to your workout, an Energy Bar is a practical option.
Each RED-Scue Energy Bar provides:
38 g carbohydrates per 70 g bar
Vanilla Cinnamon Energy Bar
Best before:
✓ Strength sessions
✓ Olympic lifting
✓ Morning workouts
✓ When you want a familiar, lighter flavour
Lemon Drizzle Energy Bar
Best before:
✓ Conditioning sessions
✓ Warmer training days
✓ When appetite is lower
✓ When you want a lighter option
During Longer Sessions
Most CrossFit classes do not require fuelling during the workout.
However, additional carbohydrate can be useful during:
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Longer training sessions
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Competition days
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Multiple workouts in one day
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High-volume training blocks
Salted Caramel Energy Bar
Best for:
✓ Longer sessions
✓ Competition days
✓ When you need reliable carbohydrate
✓ When you want a more satisfying flavour
After Training: Support Recovery
Recovery begins after the workout finishes.
Your body needs carbohydrates to replenish glycogen and protein to support muscle repair.
However, many athletes struggle to eat immediately after hard sessions.
Chocolate Chip Energy Bar
Best after:
✓ Regular WODs
✓ Strength sessions
✓ When your next meal is delayed
Orange Chocolate Energy Bar
Best after:
✓ Hard conditioning sessions
✓ Competition days
✓ Higher-volume training blocks
For bigger recovery needs:
Cacao Breakfast Fuelling Jar
65 g carbohydrates per 120 ml jar
Ideal after:
✓ Hard training days
✓ Double sessions
✓ When you need a larger carbohydrate top-up
Example CrossFit Fuelling Days
Morning Strength Session
2 hours before:
Vanilla Breakfast Fuelling Jar
After:
Protein + carbohydrate breakfast
Evening CrossFit Class
30–60 minutes before:
Vanilla Cinnamon or Lemon Drizzle Energy Bar
After:
Balanced meal or Chocolate Chip Energy Bar if delayed
High-Volume Training Day
Before:
Vanilla Breakfast Fuelling Jar
During:
Salted Caramel Energy Bar if needed
After:
Cacao Breakfast Fuelling Jar or Energy Bar alongside protein
The Bottom Line
CrossFit athletes are not just training muscles.
They are training strength, power, conditioning and the ability to repeatedly perform under fatigue.
Carbohydrates support that work.
Energy supports adaptation.
Consistent fuelling helps you get more from every session.
The strongest athletes are not only the ones who train hardest.
They are the ones who support that training with the right fuel.
Fuel first.
Train better.
Perform stronger.
Fuel Without Fear.
