Let me ask you something…

How old is your body?

And no, I don't mean the number on your driver’s license.

I mean how old does your body actually function?

Because here's something I've learned after more than four decades of working with bodies:

Your chronological age and your biological age are not necessarily the same thing.

Your chronological age is easy. That's simply how many birthdays you've had.

I'm 69.

There. I said it.

But here's the thing…

69 doesn't tell you a damn thing about what my body can do.

And that's where biological age gets interesting.

So What the Heck Is Biological Age?

Biological age is basically an estimate of how your body is aging based on how well different systems are functioning.

We're talking about things like:

Strength.

Cardiovascular fitness.

Mobility.

Balance.

Metabolic health.

Recovery.

Sleep.

And overall physical function.

So you could have two people who are both 65 years old chronologically…

…and their bodies could tell two completely different stories.

Let Me Give You an Example

Let's say we have two women.

Both are 65.

Woman number one walks regularly. She strength trains. She can climb stairs. She can get down on the floor and get back up. She carries her own groceries. She has good balance and decent cardiovascular fitness.

She's 65.

But her physical function may look more like someone younger.

Now let's look at woman number two.

She's also 65.

But she spends most of her day sitting. She's lost a lot of muscle. Stairs leave her gasping. She has trouble getting up from a chair without using her hands. She's afraid of getting down on the floor because she's not sure she can get back up.

Same birthday age.

Completely different bodies.

That's biological aging versus chronological aging.

And this is where I want you to stop obsessing over the number.

Because I don't care if you're 49, 59, 69, or 79.

I want to know:

What can you DO?

Here's My Favorite Biological-Age Test

Forget the fancy equipment for a minute.

Stand up from your chair.

Can you do it without using your hands?

Now walk across the room.

Turn around.

Walk back.

Can you do that comfortably?

Stand on one leg.

How long can you balance?

Reach overhead.

Can you?

Get down onto the floor.

And here's the big one…

Can you get back up?

Because if you can't get down there, that's one thing.

But if you get down there and then start looking around the room thinking,

"Okay…how the hell am I getting back up?"

We've got some work to do!

And I'm not saying that to make you feel bad.

I'm saying it because that's information.

Your body is giving you information about strength, mobility, balance, coordination, and confidence.

And information is powerful because once you know what needs work…

you can work on it.

Your Biological Age Isn't a Tattoo

This is really important.

Your biological age isn't necessarily some permanent number stamped on your forehead.

Your body adapts.

That's one of the most exciting things about it.

You can get stronger.

You can improve your cardiovascular fitness.

You can improve balance.

You can improve mobility.

You can build muscle.

You can become more physically capable.

Does that mean you can magically make your body 25 again?

No.

And frankly, I'm not interested in going back to 25.

Have you met 25-year-olds?

They're exhausted!

I'm kidding.

Sort of.

What I am interested in is making the body you have today as strong, capable, and resilient as possible.

How Do You Actually Find Out Your Biological Age?

This is where things get a little complicated.

There isn't one magical test that says:

"Congratulations! Your body is 57."

You can have biological-age assessments that look at blood markers, cardiovascular fitness, body composition, or even things like DNA methylation.

Those can be interesting.

But different tests measure different things, and they can give you different results.

So I wouldn't put all your eggs in the biological-age-test basket.

Instead, look at the whole picture.

How strong are you?

How's your balance?

How's your cardiovascular fitness?

What's your blood pressure?

How's your blood sugar?

How well are you sleeping?

How quickly do you recover from exercise?

How easily can you perform everyday activities?

And perhaps most importantly:

Are you getting better or worse?

Because that's the number I really want you watching.

Don't Try to Be Younger. Try to Be Better.

This is where I think we get aging completely wrong.

We're constantly being told to look younger.

Lose the wrinkles.

Hide the gray.

Look 10 years younger.

Blah, blah, blah.

But what if we stopped making "looking younger" the goal?

What if the goal was:

Move better.

Get stronger.

Improve your balance.

Keep your independence.

Have the stamina to travel.

Be able to get off the floor.

Carry your own suitcase.

Play with your grandchildren.

Get out of the chair without making that little noise we all make!

You know the one.

"Uhhhhhh."

We all know it.

That's the stuff that matters.

Here's My Cattitude on Aging

I can't change my chronological age.

Neither can you.

Every year, whether you like it or not, you're going to get another birthday.

But I refuse to believe that getting older means automatically becoming weaker, stiffer, slower, and less capable.

Aging happens. Decline isn't something we have to simply surrender to.

There are things we can do.

We can train.

We can move.

We can build muscle.

We can challenge our balance.

We can work on mobility.

We can take care of our cardiovascular system.

We can recover.

And we can keep asking our bodies to do things.

Because here's what I believe:

Your birthday tells me how long you've been alive.

Your body tells me how you're aging.

And I'm a whole lot more interested in what your body can do than the number on your cake.

So don't ask yourself:

"How old am I?"

Ask:

"How capable am I?"

And then ask the really important question:

"What can I do today to become even more capable tomorrow?"

Now THAT is a number worth working on.

Keep it moving.