The Secret Running Metric That Could Slash 10 Minutes Off Your Marathon
Estimated read time: 3.36 minutes (about how long it takes my dog Augie to decide between post-run ice cream flavors 🍦)
Hey Performance Nerds! Jonah here. 🤓
Want to run 10 minutes faster in your next marathon? Here's the science-backed secret most runners miss: optimizing your leg stiffness can boost your speed by 8%! 🏃♂️💨
This post originally came from a guest blog I wrote for my friends over at Stryd, but I’m sharing it here because sharing free science is way more fun.
Here’s what’s inside:
🧪 The science behind leg stiffness (and why it’s the key to faster marathons).
📊 Two key metrics to track your progress.
💪 Easy exercises to build stronger, springier legs.
Oh, and don’t miss this: Grab your free Calf & Ankle Blueprint at the end of this email—a gym plan to boost your leg stiffness before it goes on sale next week!
Let’s bounce into it! (I know, I’m not funny.)
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The Secret Spring in Your Step 👟
Ready to learn why most runners waste 30% of their energy with this 2nd-grade science experiment? 🧪
Imagine two rubber bands: one stiff, snapping back instantly when stretched, and one loose and floppy, slowly returning energy.
Your Achilles tendon works just like these rubber bands. A stiff Achilles quickly bounces back with every step, efficiently handling impact forces.
When your "springs" are working right, your muscles don't have to work as hard. That means more speed with less energy!
Stiff Achilles, No Worries: The Secret to Bouncing Like a Pro (and Not Like a Floppy Rubber Band).
Here's the mind-blowing part: Research shows that improving leg stiffness boosts running economy by 4% - that's the SAME boost you get from those $250 super shoes! 🤯
Except this upgrade works in every shoe you own. Sorry, not sorry, wallet!
Absorbing free energy is crucial for efficient running. The more your Achilles handles these forces, the less work your calf muscles do.
1. Vertical Stiffness: The Bounce Factor ⬆️
Elite runners glide with minimal up-and-down movement. This is called vertical stiffness. The less you bounce, the more energy you conserve for forward motion.
2. Leg Stiffness: Your Natural Super Shoe 🦿
Think of your legs as Formula 1 racing springs: better springs = faster running with less effort. It’s like upgrading from a rusty Toyota to a Tesla (no offense, Toyota fans 🚗➡️⚡).
Track Your Springs: Two Key Metrics 📊
Vertical Oscillation (Your Bounce Score)
Measures how much you’re bouncing up and down (aka wasted vertical motion)
Lower numbers = more efficient running
Fun fact: Elite runners are pros at keeping their bounce minimal!
Ground Contact Time (Your Spring Power)
Tracks how long your foot stays on the ground with each stride
Lower ground contact time over time might indicate stronger, more efficient springs
Pro Tip: For the best accuracy, track these metrics with a power meter or foot pod. While watch data can still provide helpful insights, all tech has its quirks and occasional errors—so don’t sweat the small fluctuations.
Even with a pod, these numbers can feel tricky to interpret. Focus on tracking long-term trends instead—that’s where the real progress happens!
Transform Your Leg Springs: The Elite Lifting Plan 💪
Warning: Most runners are making a massive mistake that's sabotaging their speed! 🚨
They think running alone builds strong leg springs. Here's the truth: Science shows your springs need SPECIFIC training to reach their full potential.
Dont panic. Here are two proven methods to improve leg stiffness: heavy strength training and plyometrics.
Tendons respond best to heavy, controlled work. Follow this science-backed protocol:
The Isometric 4% Protocol:
4 sets x 4-second heavy heel raise holds
Keep heels elevated throughout the set
Research shows this improves running economy by 4% (hello super shoes)
The Power Builder:
3-4 sets of controlled calf raises
Slow lower (count: 3-2-1-up!)
Progress weight weekly
2) Plyometric Power: Teaching Springs to Bounce
Plyometric exercises bridge the gap between strength and running explosiveness.
Quick Power Work:
3–4 sets of 5 max-effort jumps
Full rest between sets (quality beats quantity!)
Spring Drills:
Quick pogo hops (like the ground is lava!)
Start: 2 x 10 seconds
Level up: Add 5 seconds weekly
Focus: Minimal ground contact
Pro Tips That Most Runners Miss:
Train these 2-3 times weekly
NEVER before speed work or long runs
Progress slower than your ego wants
Practical Summary (For My Fellow Performance Nerds) 🧪
The Science Win:
Boost running economy by 4% (like wearing super shoes!)
Slash 10 minutes off your 3-hour marathon
Works in ANY shoes you own
Watch These Numbers: 📊
Vertical Oscillation: Lower = more efficient running
Ground Contact Time: Quick springs spend less time on the ground
Spring Training Protocol: 💪
Heavy Lifting (2-3x weekly)
4 x 4s isometric heel holds
3-4 sets slow calf raises
Bounce Training
3-4 sets x 5 explosive jumps
Pogo hops: Start 2 x 10s
Free Gift Alert! 🎁
As a thank you to this community, I'm giving away my Calf & Ankle Blueprint before it goes for sale next week!
Some of you are already crushing PRs with this blueprint. For everyone else - grab it now before it's no longer free:
➡️ Get Your Free Blueprint: Foot & Calf Gym Plan
Let's boost those springs together! Questions? Respond to this email, and I’ll get back to you! 📧
🚨Scientists Reval Some Energy Gels Might Be Lying About Their Carb Content!
Did you miss my video about how Scientists Reval Some Energy Gels Might Be Lying About Their Carb Content!? You can find it below!
I won’t lie. These videos 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 from Raw Nutrition.
What is the primary way dietary nitrates (like beetroot juice) improve running performance for new runners?
Last Week’s Results
Zone 2 aficionados, you brought your A-game! 🔥
Last week, we asked: What sets the ceiling for Zone 2 training? 🏃♂️
The correct answer is: Your first lactate threshold—the first detectable rise in blood lactate levels. At this point, your muscles shift to burning a little more carbs to produce energy (nothing wrong with this). 💪✨
Training at or below this threshold causes very little fatigue and muscle damage!
Here’s how the votes stacked up:
🟩🟩🟩🟩🟩🟩 Your first lactate threshold 🏃♂️ (163 votes)
🟨⬜️⬜️⬜️⬜️⬜️ Your second ventilatory threshold 💨 (34 votes)
⬜️⬜️⬜️⬜️⬜️⬜️ Your second lactate threshold 🔬 (24 votes)
⬜️⬜️⬜️⬜️⬜️⬜️ Your VO2 max 🫁 (11 votes)
Nerdy Finds of the Week 📚🧑🔬
This section includes my favorite research, podcasts or books about running/lifting science.
🚴 Energy Systems and Glycogen: Your body uses glycogen as its main fuel for moderate to high-intensity rides. As rides get longer, glycogen depletes, leading to fatigue if you don’t refuel.
🍌 Carb Intake Simplified: 60-80g of carbs per hour is ideal for most endurance rides. For harder efforts, increase to 90-120g/hour, though benefits above 90g may vary. Proper fueling speeds up recovery.
🥤 Gut Training: Gradually increase carb intake during training to improve tolerance and avoid GI issues. Your gut won’t absorb more carbs, but it’ll handle them better during long rides.
⚡ Glucose-to-Fructose Ratio: A 2:1 ratio is ideal for carb absorption, supporting up to 90-120g/hour. Dr. Podlogar’s research suggests a 1:0.8 ratio may be even more effective
🍳 Fasted Rides: Useful for low-intensity sessions for those who don’t train a lot. Limit to 1-2 easy rides per week. Avoid for hard efforts or those who train daily.
🍝 Carbo-Loading: For long events, eat 8-12g of carbs per kg of body weight 24-48 hours before. This maxes out glycogen stores for better endurance.
🚫 Common Mistakes: Under-fueling and waiting too long to eat. Start fueling within the first 30 minutes of your ride and stay consistent throughout.
Don’t forget: You + Science = AWESOMENESS 😎
Yours in science,
Jonah
P.S. - We have a crew of 11,500+ nerds here who are running FAST using science.
Did you need running science advice or tips? 🏃♀️💨🧪
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