Your Back Muscles May Reveal More About Aging Than You Think

New research highlights why the muscles that support your spine may be an important part of healthy aging

When most people think about losing muscle as they get older, they probably think about their legs and arms.

And for good reason. Large muscles such as the quadriceps in your thighs are important for walking, climbing stairs, getting out of a chair, and maintaining independence.

But what if we shouldn’t only be looking at the large muscles of the legs?

New research comparing the multifidus muscles of the spine with the vastus lateralis, a major thigh muscle, provides an interesting reason to pay more attention to the muscles that support your spine as you age.

The findings also reinforce an important concept behind the 6 Green Zones™: healthy aging isn’t just about how much muscle you have. It’s about maintaining the muscles responsible for stability, control, balance, and physical capacity throughout the body.

What is the multifidus?

The multifidus is a group of small muscles located along your spine.

Unlike the large muscles that help you produce powerful movements, the multifidus plays an important role in controlling and stabilizing individual segments of the spine.

Think of these muscles as part of your body’s internal support system.

They help your spine remain stable while you:

• Walk
• Bend
• Reach
• Lift
• Rotate
• Maintain an upright posture
• Move your head and body
• Respond to changes in balance

Because they work largely behind the scenes, you may not think about your multifidus very often.

But research suggests these muscles change significantly as we age.

Researchers compared the back muscle with a major thigh muscle

In a recent study, researchers compared the size of the multifidus with the vastus lateralis, a large muscle on the outside of the thigh.

They looked at younger adults and older adults, including older adults classified as having probable sarcopenia.

Sarcopenia refers to the age-related loss of muscle mass and physical function.

The researchers found that both muscles became substantially smaller with age.

Compared with younger adults:

• Multifidus size was approximately 21% smaller in older adults without probable sarcopenia.
• Multifidus size was approximately 30% smaller in older adults with probable sarcopenia.
• Vastus lateralis size was approximately 25% smaller in older adults without probable sarcopenia.
• Vastus lateralis size was approximately 30% smaller in older adults with probable sarcopenia.

In other words, the deep muscles of the spine showed a surprisingly large amount of age-related muscle loss.

Here’s the really interesting part

The researchers found that the multifidus measurements produced larger effect sizes than the vastus lateralis when comparing younger and older adults.

In simple terms, the differences in multifidus size between the groups were particularly clear and consistent.

The authors concluded that the multifidus may have greater sensitivity than the vastus lateralis for detecting probable sarcopenia.

That doesn’t mean your multifidus can diagnose sarcopenia.

It doesn’t mean that everyone with a smaller multifidus will have physical limitations.

And it doesn’t mean that simply making your multifidus bigger will prevent aging.

But it does provide an important message:

Aging affects more than the muscles we typically think about.

Your body’s deep stabilizing muscles are changing, too.

Why does this matter?

Imagine two people who are the same age.

Both are 60 years old.

One person may still have excellent balance, coordination, strength, endurance, and control.

The other may struggle with stairs, balance, prolonged standing, or getting up from the floor.

Their chronological ages are identical.

Their physical capabilities may not be.

That’s why healthy aging is about more than simply counting birthdays or measuring how much muscle you have.

We need to consider how well the body can activate, control, stabilize, and sustain movement.

This is where the 6 Green Zones™ come in

At PhysioFit of NC, we developed the 6 Green Zones™ as a way to look at six important areas of the body that can be affected by aging and changes in physical performance.

The six areas include:

1. Shoulder – the supraspinatus and rotator cuff system
2. Neck – the cervical multifidus
3. Thoracic spine – the thoracic multifidus
4. Lumbar spine – the lumbar multifidus
5. Hips – the gluteus medius and gluteus minimus
6. Calves – particularly the soleus

These aren’t the only muscles that matter.

Instead, they represent six important areas we believe deserve attention when looking at how your body is aging and maintaining physical capacity.

Why focus on these six areas?

Each Green Zone has an important job.

Your neck muscles help provide stability for the head and support precise head and eye movement.

Your thoracic and lumbar multifidus contribute to spinal stability and control.

Your hip muscles help with balance, symmetry, and lower-body control.

Your supraspinatus and rotator cuff contribute to shoulder stability and controlled arm movement.

Your calves, including the soleus, are important for walking, balance, propulsion, and maintaining the ability to move efficiently.

Together, these areas contribute to something much bigger:

Your ability to move through life with strength, stability, and confidence.

Bigger muscles aren’t necessarily better

One of the most important lessons from research like this is that muscle size isn’t the whole story.

In the study, neither multifidus size nor vastus lateralis size was a significant predictor of chair-to-stand performance after the other variables were considered.

That’s important.

It means we shouldn’t assume:

Bigger muscle = better function.

Your nervous system also has to know when and how to use the muscle.

A muscle can have adequate size but poor activation.

It can have strength but poor endurance.

It can have strength and endurance but poor coordination.

And you can have good individual muscle performance but poor overall movement because other areas aren’t contributing appropriately.

This is why we believe how your muscles perform matters just as much as how much muscle you have.

Feel It to Heal It Physio™

At PhysioFit of NC, our approach focuses on more than simply completing an exercise.

We want you to understand where you should feel the movement and whether the correct muscles are doing the work.

That’s the foundation of our Feel It to Heal It Physio™ approach.

For example, during an exercise designed to activate the gluteus medius, we don’t simply want you to complete the movement.

We want you to know:

“Am I actually feeling the muscle that is supposed to be working?”

The same principle can be applied to the multifidus, soleus, rotator cuff, and other muscles within the 6 Green Zones™.

Movement quality matters.

Don’t wait until you notice a problem

One of the biggest mistakes people make with healthy aging is waiting until something hurts or becomes difficult.

You may not notice that a muscle is becoming less active or less capable until you suddenly have difficulty doing something you used to take for granted.

Maybe it’s:

• Getting up from the floor
• Walking long distances
• Standing on one leg
• Carrying groceries
• Reaching overhead
• Turning your head while driving
• Walking up stairs
• Getting out of a chair
• Maintaining your balance

These are the abilities that allow us to remain independent.

And maintaining those abilities requires more than simply “getting stronger.”

It requires maintaining the connection, control, capacity, and consistency of the muscles responsible for movement.

Think of the 6 Green Zones™ as an early look at your physical foundation

The goal of the 6 Green Zones™ isn’t to tell you whether you’re “healthy” or “unhealthy.”

It’s a way to identify areas of your physical system that may deserve more attention.

Your results can help create a personalized blueprint for exercise and rehabilitation based on how your body is performing today.

Instead of asking:

“What is the best exercise for aging?”

A better question may be:

“What does my body need right now?”

Because there isn’t one exercise that has been proven to be the best exercise for healthy aging for everyone.

Your starting point matters.

Aging is inevitable. Declining physical capability doesn’t have to happen at the same rate.

We can’t stop the passage of time.

But we can pay attention to the physical systems that allow us to move, balance, stabilize, and remain independent.

The emerging research on muscles such as the multifidus gives us another reason to look beyond the obvious muscles of the arms and legs.

Healthy aging is a whole-body process.

And the 6 Green Zones™ provide one way to look at some of the important muscles and regions that contribute to your physical foundation.

Know your body. Find your weak links. Build your foundation.

That’s the goal of the 6 Green Zones™.

And because your physical age isn’t necessarily the same as your chronological age, understanding how your body performs today can be a valuable first step toward improving how you move tomorrow.