You’ve been putting in the miles.
The early morning runs. The long runs that take up your weekend. The tempo workouts, easy miles, strength sessions, and everything in between.
And maybe lately, you’ve started noticing something.
Your knee feels a little sore after a long run.
Your calf feels tighter than usual.
Your hip has been bothering you during the last few miles.
Your Achilles feels stiff when you get out of bed.
Or maybe nothing actually hurts, but your stride just doesn’t feel quite the same.
So you tell yourself:
“It’s probably nothing.”
For marathon runners, that can be an easy mindset to fall into.
But with the 2026 Bank of America Chicago Marathon coming up on October 11, now is not the time to ignore the small things.
It’s the time to find out what your body is telling you.
The Problem With Waiting Until Something Hurts
Marathon training places a tremendous amount of repetitive stress on your body.
One run usually isn’t the problem.
It’s the accumulation of thousands of steps over weeks and months of training.
A small limitation in mobility, weakness in a muscle group, an old injury, or a change in your running mechanics may not bother you during a short run.
But as your mileage increases, that same issue can become harder for your body to compensate for.
That’s why many runners don’t suddenly develop a problem.
Instead, they notice small signs first.
Maybe your usual 6-mile run feels fine, but your knee starts aching around mile 8 of your long run.
Maybe your calf is always tight the day after running.
Maybe one side feels stronger than the other.
Maybe you keep stretching the same area because it never quite feels loose.
Maybe you’ve had an injury before and you’re wondering if it could come back once your mileage increases.
These are the things worth paying attention to.
“But I Can Still Run…”
This is one of the most common reasons runners put off getting checked.
“I can still run, so it can’t be that serious.”
You may be right.
But being able to run doesn’t necessarily mean everything is moving and loading efficiently.
Your body is incredibly good at finding ways to keep you moving.
If one area isn’t doing its job well, another area may compensate.
You might still be able to complete your run while gradually putting more stress on another part of your body.
That doesn’t mean you’re injured.
It means there may be something worth looking at.
And that’s exactly where a pre-marathon injury screen can be useful.
What Is a Pre-Marathon Injury Screen?
A pre-marathon injury screen is a focused look at how your body is handling the demands of your training.
Instead of waiting until you’re dealing with significant pain, the goal is to identify areas that may need attention before they interfere with your training or race day.
Depending on your individual needs, a screen may look at things such as:
- Strength and muscular control
- Mobility and flexibility
- Movement patterns
- Running mechanics
- Previous injury areas
- Current aches or recurring discomfort
- Side-to-side differences
- Areas that may be struggling as your training volume increases
The goal isn’t to tell every runner that something is wrong.
The goal is to understand what your body is doing right now and determine if there are areas that could benefit from attention before October 11.
You Don’t Have to Be Injured to Get Screened
This is important.
A pre-marathon screen isn’t only for runners who are already dealing with pain.
It can also be helpful if you’re thinking:
“I feel pretty good, but I want to make sure I’m not missing something.”
Maybe you’re running your first marathon.
Maybe you’ve run Chicago before and want to approach this training cycle differently.
Maybe you’ve had an ACL, knee, hip, ankle, or back injury in the past.
Maybe you’ve increased your mileage significantly.
Maybe you’ve started noticing that one side feels different from the other.
Or maybe you’ve simply reached the point in training where you want another set of experienced eyes on how you’re moving.
You don’t need to wait until you’re sidelined.
What About Those “Little” Aches?
Let’s say your knee hurts a little after your long runs.
Or your Achilles is stiff in the morning.
Or your hip starts getting uncomfortable toward the end of your run.
You might think:
“I’ll see how it feels next week.”
Then next week comes.
It’s still there.
So you modify your run.
Then it comes back again.
This doesn’t automatically mean you’re heading toward an injury.
But recurring symptoms are information.
Instead of repeatedly hoping the problem disappears, it can be useful to understand why it’s happening and whether something in your training, movement, strength, mobility, or running mechanics needs to be addressed.
The earlier you understand the problem, the more options you may have to work with it.
Your Marathon Training Shouldn’t Be Just About Running More
When you’re training for a marathon, it’s easy to focus almost entirely on mileage.
How many miles did you run?
How long was your long run?
Did you hit your pace?
Did you complete your workout?
But your ability to handle marathon training isn’t determined by mileage alone.
Your body also needs the strength, mobility, coordination, and capacity to handle the repetitive demands you’re asking of it.
That’s why looking at the bigger picture can be valuable.
You aren’t just training your cardiovascular system.
You’re preparing your entire body to run 26.2 miles.
Give Yourself Time to Make Adjustments
One of the biggest reasons to consider a screen before race day is simple:
Time matters.
If you wait until the week before the Chicago Marathon to address a problem, your options are much more limited.
If you identify a concern earlier in your training, you have more time to make appropriate adjustments.
That could mean addressing a strength limitation.
Working on mobility.
Changing how you’re approaching part of your training.
Modifying an aggravating activity.
Improving your running mechanics.
Or simply having a better understanding of what your body needs as you continue training.
The goal isn’t to change everything you’re doing.
It’s to make sure you aren’t ignoring something that deserves attention.
Running Chicago? This Is Your Time to Check In
The Chicago Marathon is more than another long run.
You’ve spent months preparing for those 26.2 miles.
You’ve built your mileage.
You’ve committed to your training.
You’ve probably rearranged your schedule around your long runs.
You’ve put in the work.
So don’t let an issue you’ve been ignoring become the thing that changes your race-day plans.
If something has been bothering you, get it checked.
If you’ve had a previous injury, consider having it looked at before your mileage peaks.
And even if you feel good, a pre-marathon screen can give you a clearer picture of how your body is handling your training.
Get Ahead of the Problem Before Race Day
At PREP Performance Center, our Pre-Marathon Injury Screen is designed for runners preparing for the demands of race day.
We’ll look at your individual movement, strength, mobility, running mechanics, and areas of concern to help identify what may need attention as you continue training.
Because the goal isn’t simply to make it to the starting line.
It’s to give your body the preparation it needs to get you there ready.
Running the 2026 Chicago Marathon?
October 11 will be here before you know it.
Don’t wait for a small problem to become the reason you have to change your training.
Get your Pre-Marathon Injury Screen at PREP Performance Center and find out what your body needs before race day.
REQUEST YOUR PRE-MARATHON INJURY SCREEN
Want a deeper look at your running?
If you’re interested in understanding your running mechanics in more detail, check out our Running Performance Analysis at PREP Performance Center.