Why Your Calves—Not Your Glutes—Are Your Real Running Engine
Estimated read time: 3.6 minutes (about as long as it takes to foam roll your IT band...realizing it does nothing for you). 😉
Hey Performance Nerds! Jonah here. 🤓
Your glutes get all the credit. But your calves?
They’re quietly doing 8x your bodyweight in work every step.
And most runners haven’t trained them once this year.
Today we’re breaking down:
Why your calves—not your glutes—are your real running engine
How weak calves trigger the dreaded marathon bonk
My go-to protocol for building bulletproof, race-ready calves
(Augie, my dog, is still unconvinced. He insists biceps are the key to speed. Which explains why the mailman keeps winning.)
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You’ve heard “glutes drive the stride,” but here’s the truth:
Your soleus—the deep calf muscle—does 3x more work than your glutes every step.
📊 And the calf-Achilles complex?
Research shows it delivers up to 50% of your forward propulsion. That springy push-off in mile 23? All calf.
Most runners treat their calves like assistants.
But they’re the CEO of your stride.
❌ The “Tight Calves” Lie We All Fell For
Raise your hand if you’ve ever thought: “My calves are always tight—I need to stretch more.”
Not quite.
That “tight” feeling might be your nervous system putting on the brakes, because your calves can’t handle the load you’re asking them to carry.
Let’s break it down:
Weak muscles trigger protective tension
That tension = the tightness you feel
You stretch... and nothing changes
“If the only tool you have is stretching, every tight calf looks like a flexibility problem. But it’s usually a strength one.”
— Paraphrased from Dr. Peter Malliaras
🧠 Stretching a weak calf is like resetting the check engine light instead of fixing the engine. Feels nice, solves nothing.
Want calves that don’t feel tight all the time? Strengthen them.
💣 Your Bonk Might Start Lower Than You Think
We love to blame bonking on carbs or pacing. And yeah, they still matter (love you forever, pasta).
But calf fatigue might also be part of the story.
Here’s the chain reaction:
❌ Calves fatigue → loss of elastic recoil
♻️ Glutes + quads scramble to compensate
🧃 Energy cost skyrockets
🪫 Form breaks down—and the shuffle begins
“Fatigue is the enemy of motor control. The stronger and more resilient a muscle is, the longer it can hold the line.”
— Dr. Bryan Heiderscheit
Strong calves = efficient movement late in the race.
Weak calves = biomechanical chaos.
🏋️️ Build Calves That Don’t Quit: My Go-To Protocol
These are the exact exercises I use with athletes to build durable, fatigue-resistant calves that hold up on race day.
Exercise names are links to demo videos.
Exercise | Sets x Reps | Notes |
|---|---|---|
3 sets of 4 x 4 sec Push / Hold | Push hard for 4 seconds, rest for 4 seconds and repeat. 4 rounds is 1 set! | |
Smith Single Leg Calf Raise (can perform holding dumbell in 1 hand too) | 3 x 6-10 Reps / Leg | Elevate the front of your foot with a small box or plate. |
3 sets of 4 x 4 sec Push / Hold | Push through Front of Foot / Big Toe. Heavy weight so can't move machine. | |
3 sets of 4 x 4 sec Push / Hold | Push hard for 4 seconds, rest for 4 seconds and repeat. 4 rounds is 1 set! |
Do 2x/week post-run or in a dedicated strength session
Progress load every 2 weeks
⚡️ TL;DR – Your Race Depends on Calves You’ve Been Ignoring
Let’s land the plane:
Key takeaways:
Your calves handle 8x your bodyweight every step, more than any other muscle.
“Tight” = weak and overloaded—not inflexible.
Strength training > stretching for real calf resilience.
Bulletproof calves = more speed, fewer injuries, stronger finishes.
💬 One last thing before you go.
After the NFL, I wasn’t sure if obsessing over performance science still mattered, until I started helping this community.
Your training goals? They brought that fire back.
So if you're feeling stuck, second-guessing something, or just want to share how training's going—hit reply. I read every message, and I’m here to help however I can.
🚨 That Post-Workout Cold Plunge Might Be Working Against You 🧊❄️
Did you miss my post about how that post-workout ice bath might be working against you 🧊❄️? You can find it below!
I won’t lie. These posts take me a while to make. If you find it helpful, share it on your story or with a friend. It helps me a ton!
Are You a True Running Nerd? Prove it.. 🧐
Welcome to the prove you’re a nerd section. Each week, I ask a question about a common running science myth.
Answer correctly, and you’ll be entered into a weekly raffle to win a package of Jonah’s favorite supplements.
For what race distance does research suggest taking gels during event can meaningfully improve performance?
Last Week’s Results: The Liver Logs Miles Too 🧪
Muscles get the spotlight, but your liver's pulling serious weight behind the scenes, especially once the miles pile up. Most of you nailed it (though a few votes went astray into sodium-filtering fantasy land 😅).
The correct answer?
C. Maintaining blood glucose by releasing stored carbs ✅
Think of your liver as a smart fuel pump: it steadily releases glycogen to keep blood sugar stable when your muscles—and brain—need it most. Without that backup system, you'd hit the wall well before the finish line.
Here’s how the votes shook out:
⬜️ A. Regulating sweat rate by filtering sodium – 13 votes
⬜️ B. Producing red blood cells to carry oxygen – 13 votes
🟩 C. Maintaining blood glucose by releasing stored carbs – 223 votes ✅
🟨 D. Filtering lactic acid out of the bloodstream – 59 votes
Bottom line?
If you’re still cruising at mile 18, it’s not just your training—it’s your liver keeping your tank topped up and your brain online. 🧠🍬
Don’t forget: You + Science = AWESOMENESS 😎
Yours in science,
Jonah
P.S. - We have a crew of 17,230+ nerds here who are running FAST using science.
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