What if everything you thought you knew about running… wasn’t entirely true?
Every year, runners ask the same questions—about knees, fueling, shoes, and strength training. And while the questions haven’t changed much, the science absolutely has.
So instead of recycling old advice, I went straight to the research (with a little help interpreting it from my in-house doctor).
Here’s what the latest data actually says about the four most Googled running questions of 2026—and what it means for how you train moving forward.
1. Is Running Bad for Your Knees?
It’s probably the most persistent myth in running: that every mile you log is slowly wearing your knees down.
MYTH: Running wears down your knees and leads to arthritis.
WHERE THIS CAME FROM:
The logic feels intuitive—use something more, and it wears out faster. Like tires on a car.
WHAT WAS BELIEVED (INCORRECTLY):
That cartilage is a fixed, non-renewable tissue that simply deteriorates with impact.
STUDY:
Quantitative MRI reveals infrapatellar fat pad changes after running a marathon (2025)
READ THE STUDY:
https://pmc.ncbi.nlm.nih.gov/articles/PMC11930216/
HOW THE STUDY WAS CONDUCTED:
- 22 amateur marathon runners
- MRI scans before and after a marathon
- Focus on knee structures and joint environment
CONCLUSION:
The knee isn’t a passive structure—it’s adaptive. The study showed measurable changes in the infrapatellar fat pad, suggesting improved cushioning and function after running.
Other research supports this:
- No increase in bone damage
- Improvements in joint structures
- Increased synovial fluid (your body’s natural lubricant)
WHAT THIS MEANS FOR YOU:
Your knees aren’t breaking down—they’re responding to stress and adapting.
When training is done properly, running doesn’t destroy your joints. It can actually help maintain them.
2. How Many Carbs Can You Really Process Per Hour?
For years, runners have followed the same fueling rule: don’t exceed 60–90 grams of carbs per hour.
Turns out, that ceiling may have been too low all along.
MYTH: You can only absorb 60–90 grams of carbs per hour.
WHERE THIS CAME FROM:
Older studies focused on single carbohydrate sources like glucose, which max out absorption quickly.
WHAT WAS BELIEVED (INCORRECTLY):
That anything above ~90g/hour would go unused—or lead straight to GI distress.
STUDY:
High-carb fueling research published in the Journal of Applied Physiology (2025)
READ THE STUDY (BREAKDOWN ARTICLE AND STUDY):
https://marathonhandbook.com/elite-marathoners-can-burn-more-carb-at-120-grams-per-hour/
HOW THE STUDY WAS CONDUCTED:
- Elite marathon runners
- Compared 60g, 90g, and 120g of carbs per hour
- Measured performance and metabolic efficiency
CONCLUSION:
At 120g per hour, runners became more efficient—using fuel better and reducing the energy cost of running.
The limitation wasn’t absorption. It was tolerance.
WHAT THIS MEANS FOR YOU:
You might be underfueling your runs.
Instead of asking how much your body can handle, start asking how much it can learn to handle.
Because your gut—just like your legs—can be trained.
3. Do More Cushioned Shoes Protect You More?
Running shoes have gotten bigger, softer, and higher than ever before. But is more always better?
MYTH: More foam equals more protection and fewer injuries.
WHERE THIS CAME FROM:
The maximalist shoe boom, where brands competed to build the tallest midsoles possible.
WHAT WAS BELIEVED (INCORRECTLY):
That more cushioning automatically reduces stress on the body.
STUDY:
The effects of running shoe stack height on running style and stability (2025)
READ THE STUDY:
https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2025.1526752/full
HOW THE STUDY WAS CONDUCTED:
- ~17–18 runners
- 3D motion capture analysis
- Compared stack heights: 27mm vs. 35mm vs. 50mm
CONCLUSION:
Higher stack heights:
- Reduced hip stability
- Increased inward foot roll
- Made runners work harder to stay balanced
In short: more cushioning came with less stability.
WHAT THIS MEANS FOR YOU:
Super shoes aren’t inherently bad—but they’re not a one-size-fits-all solution.
They can improve performance, but they also change how your body stabilizes itself.
👉 The smarter approach: rotate shoes and match them to your run—not just the trend.
4. Will Strength Training Make You Slow?
This one feels like it should’ve disappeared years ago—but it’s still one of the most searched questions in running.
MYTH: Lifting weights makes runners bulky and slow.
WHERE THIS CAME FROM:
The old “interference effect” theory—that strength and endurance cancel each other out.
WHAT WAS BELIEVED (INCORRECTLY):
That runners should avoid heavy lifting and stick to light weights and high reps.
STUDY:
Effects of heavy strength training on running performance in endurance athletes
READ THE STUDY:
https://pubmed.ncbi.nlm.nih.gov/21364470/
BONUS (ACSM GUIDELINES OVERVIEW):
https://acsm.org/resistance-training-guidelines-update-2026/
HOW THE STUDY WAS CONDUCTED:
- Female endurance athletes
- Added heavy strength training to their routine
- Measured running performance and efficiency
CONCLUSION:
Heavy strength training:
- Did not reduce performance
- Improved running economy
- Increased power and efficiency
Other findings show:
- Training at >80% of max strength is most effective
- Gains of 2–8% in running economy
WHAT THIS MEANS FOR YOU:
Strength training isn’t making you slower—it’s making you more efficient.
You’re not building bulk. You’re building a stronger, more resilient system that can handle higher mileage.
Final Thoughts
If there’s one takeaway from all of this, it’s this:
Your body is not fragile—it’s adaptable.
- Your knees adapt
- Your gut adapts
- Your muscles adapt
- Even your biomechanics adapt
The real risk isn’t doing too much.
It’s underestimating what your body is capable of learning.
