You’re Strong. But Are You Fit? The 5 Things That Actually Make Up Fitness
Ask ten people what it means to be fit and you'll probably get ten different answers.
One person points at their 180kg deadlift.
Another tells you their 5K time.
Someone else has visible abs.
And there's always that one person whose resting heart rate somehow becomes part of every conversation.
All impressive.
None of them, on their own, tells us whether someone is genuinely well-rounded physically.
Because fitness isn't one thing.
And in 2026, the American College of Sports Medicine has put an updated framework around exactly what we should be looking at.
There are five major components of physical fitness:
Cardiorespiratory fitness. Muscular fitness. Body composition. Flexibility. Neuromotor fitness.
That last one might be unfamiliar.
We'll get to it.
Because once you look at fitness this way, something becomes pretty obvious:
You can be very good at one part of fitness while completely neglecting another.
1. Cardiorespiratory fitness: how well can your engine work?
This is the bit most people simply call "cardio".
Running. Cycling. Swimming. Rowing. Brisk walking. Conditioning work.
But cardiorespiratory fitness isn't really about whether you enjoy spending 45 minutes on a treadmill.
It's about your body's ability to take in oxygen and deliver it where it's needed during sustained physical activity.
And yes, it matters even if your main goal is getting stronger.
The NHS currently recommends that adults aim for at least 150 minutes of moderate-intensity activity or 75 minutes of vigorous-intensity activity per week, alongside muscle-strengthening activity.
So being able to squat a small family car doesn't give you a lifetime exemption from cardio.
Sorry.
The good news is that cardio doesn't have to mean endless jogging.
Choose something you'll actually do consistently.
That's far more useful than choosing the supposedly "perfect" form of cardio that you hate so much you abandon it after eleven days.
2. Muscular fitness: more than just strength
This is Strivonex Coach territory.
But there's an important distinction.
ACSM's updated framework places strength, muscular endurance and power within muscular fitness.
They're related.
They're not identical.
Strength is your ability to produce force.
Muscular endurance is your ability to repeatedly produce or sustain muscular effort.
Power is about producing force quickly.
Someone can therefore be exceptionally strong without necessarily having exceptional muscular endurance or power.
This is one reason a well-designed programme starts with the outcome you're actually trying to improve.
Training isn't just collecting exercises.
Your body adapts to the demands you repeatedly place on it.
And for general health, the NHS recommends strengthening activities that work all the major muscle groups on at least two days per week.
3. Body composition: useful information, terrible identity
Here's where fitness conversations often go sideways.
Body composition describes things such as fat mass and fat-free mass.
It can be useful information.
But your body-fat percentage isn't your personality.
And a lower number isn't automatically proof that you're fitter.
Someone can look lean while having poor cardiorespiratory fitness.
Someone carrying more body fat can be strong, active and improving multiple areas of physical fitness.
Someone can lose weight while simultaneously losing muscle.
Context matters.
The useful question isn't:
"How small can I make this number?"
It's:
"Does my body composition support my health, performance and goals?"
That's a much better conversation.
4. Flexibility: no, you don't need to become a human pretzel
Flexibility is the ability of a joint to move through the range needed for movement and everyday activity.
That doesn't mean everyone needs to be able to fold themselves into positions normally associated with airport luggage.
You need enough mobility and flexibility for your life, your training and your goals.
The NHS notes that flexibility can help maintain the movement required for everyday tasks and physical activity, while strength and flexibility work can contribute to maintaining physical function as we age.
A weightlifter, gymnast, footballer and 70-year-old wanting to comfortably get down onto the floor and back up again don't necessarily require identical levels of flexibility.
Again:
Fitness is individual.
5. Neuromotor fitness: the one people forget
This is probably the most interesting part of the updated framework.
Neuromotor fitness includes qualities such as agility, balance and gait speed.
In simple terms, it's partly about how effectively your nervous system and body work together to control movement.
Think balance.
Coordination.
Changing direction.
Reacting.
Moving confidently.
These qualities become particularly important as we get older.
The NHS specifically highlights exercises that improve leg strength, balance and coordination as useful for maintaining muscle strength and helping reduce falls in older age.
And here's the thing:
You don't necessarily notice that you've neglected these abilities while you're young.
Then one day someone asks you to stand on one leg while putting a sock on and suddenly you've discovered a sixth component of fitness:
survival.
