Estimated read time: 5.31 minutes (about as long as Sawe needed for the last 4K of London 🤔)

Hey Performance Nerds! Jonah here. 🤓

Sebastian Sawe ran 1:59:30 in London. Yomif Kejelcha followed in 1:59:41 in his marathon debut. Everyone wants to credit the shoes. The honest answer is that five things came together in the same race at once.

Here's what you'll learn today:

(Augie watched the broadcast with me. He concluded all five guys clearly need a treat. He's not wrong.)

I rebuilt the referral prizes this week, and the top tier is now free gear, gels and a 1:1 call with me. Fifty friends between you and an hour on my calendar (and Augie’s) to pick apart your training.

Look at the prize ladder when you scroll down. I picked rewards I'd want.

Something else is brewing in May. Just look.

The gel I race with (and why):

BETA FUEL: delivers 40g of carbs per serving through a 1:0.8 maltodextrin-to-fructose ratio.

That ratio is why I've never had a GI issue with it in 3 years of racing. Fast absorption, no gut bombs. I don't earn a commission on this. I negotiated 15% off for you because I believe in the science behind it.

Marathon Science subscribers get 15% off one-time purchases with code JONAH26. Live now through May 31.

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💡 See this week’s full Stryd training tip at the end of this newsletter.

Marathon performance used to sit on three legs. We now know there's a fourth.

A runner who looks the same at km 35 as at km 5 built a different engine. That's durability.

The training that protects it isn't just more miles.

Zanini and colleagues (2025) tested two strength-and-plyo sessions per week in trained runners. The training group held running economy late in long runs. The control group fell off earlier.

A separate Zanini line of work points to volume. Weekly long runs over 90 minutes, with marathon-pace segments inside, build the same protection.

What this means for you: Late-race fade isn't only a fueling problem. Two strength and plyo sessions per week protect economy at the back end. So does one well-built long run.

Three structural features show up across Sawe's training:

Easy volume is the aerobic base everything else stacks on. The hard sessions raise the ceiling. The MP block teaches your legs to hold pace late.

Two hard sessions a week is a hallmark of the elite Norwegian model. Marathon-pace work links it to late-race economy.

Sawe's reported training week looks like this:

(Reported context, not a validated protocol)

What this means for you: Don't copy 150 mpw. Copy the structure. Add marathon-pace blocks inside one existing long run a week.

Pair it with two hard sessions and an easy aerobic base. Scale weekly volume to what the rest of your life supports.

(Copy-pasting elite mileage is a recipe for the orthopaedic surgeon, not the start line.)

Super shoes keep getting lighter. The new Adidas Adios Pro Evo 3 weighs 97 grams in a men's size 9.5.

Reported gain: 1.6% better economy than the Pro Evo 2. That's part of why the headlines talked about the shoes.

Your foot swings through a much wider arc than your hips do every stride. Weight on your foot costs more energy than weight anywhere else. Lighter shoe, less work.

The other half of the effect is the plate-and-foam system, which returns more stride energy.

The well-replicated anchor comes from Hoogkamer and colleagues (2018). RCT, 18 sub-elite runners, prototype super shoe vs two marathon racing shoes. The super shoe cut the energy cost of running by about 4%.

At sub-2 pace, a 1% economy edge across 26.2 miles can be a minute on the clock.

Lighter shoes cost less to swing. That's well-documented.

The economy gain shrinks as pace slows, but doesn't disappear. Slower runners still benefit, just less than elites.

What this means for you: The advantage is biggest at fast paces. If you're racing seriously, the new wave of sub-100g super shoes is worth a look.

Note: the Pro Evo 3 itself doesn't have its own RCT. The 4% number traces to the prototype literature.

Elites are pushing carb intake higher than ever because their metabolic demand keeps climbing. High-carb fueling defends marathon durability: the late-race economy and pace that fade when carbs run low.

The trick is mixing glucose with fructose. That lets your gut absorb carbs from two paths, which is how runners get past 60 g/hr.

Ravikanti and colleagues (2025) showed 120 g/hr improved running economy by about 3% compared with 60 g/hr. Carb-fed muscle keeps using carbs longer, leans on fat less, and uses less oxygen at race pace.

Carbs squeeze more energy out of each breath of oxygen than fat does.

You have to earn the higher rate. Gut training over weeks raises can lowers GI symptoms.

Sawe's reported plan: ~25 g at the start, ~25 g per 5 km, a caffeine gel near 20 km. About 230 g total, or roughly 115 g/hr. Sourced to a Maurten team statement.

What this means for you: Most runners only need 90 g/hr or less. But you still have to gut-train to it.

Spend several weeks practicing your highest tolerable rate in long sessions before race day.

That's how you handle high carbs without GI distress.

At altitude, there's less oxygen in the air.

Your body responds by making more red blood cells. The trigger is a hormone called EPO.

When you come back down to sea level, those extra red blood cells let you carry more oxygen at race pace. That's what raises your VO2max.

Levine and Stray-Gundersen (1997) ran the foundational study. 39 collegiate runners across three groups. The live-high/train-low group gained more red-cell mass and VO2max than the other two. They also ran a faster 5K.

Sawe and his team have voluntarily entered extra anti-doping testing per AP coverage on April 27.

What this means for you: Altitude works, but a meaningful share of athletes are non-responders. A heat or altitude block before a goal race may help. It isn't a guarantee.

Each pillar is a multiplier, not an additive.

Take any one out and the time gets slower.

That's why "the shoes did it" is wrong. It's also why anyone chasing a PR by changing one variable ends up frustrated.

Bottom line: Sub-2 wasn't an accident, and it wasn't the shoes. Five things compounded on the same day. Chase the structure underneath the headline.

Jonah

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.

More carbs sounds like more energy. But your gut plays by different rules than your legs, and a lot of you felt that tension in this one.

The correct answer?
A. The extra carbs sit in the gut, pull in water, and increase GI distress risk 🌊⚠️ ✅

When carb intake exceeds what your gut can absorb, those carbs just sit there. They pull water into the intestines, slow gastric emptying, and that’s when sloshing, bloating, and emergency porta-potty stops show up.

Here’s how the votes shook out:
🟩 A. The extra carbs sit in the gut, pull in water, and increase GI distress risk 🌊⚠️ – 233 ✅
⬜️ B. You blunt carb oxidation, which makes you more likely to bonk late 🥑📉 – 6
⬜️ C. You dilute sodium levels by over-consuming fluids with carbs, increasing cramp risk 💧🧂 – 6
🟨 D. You overwhelm muscle glycogen storage, so the carbs stop helping 🚫🔋 – 14

A handful of you went with glycogen storage limits.

Understandable. But during a race, the bottleneck isn’t your muscles refusing carbs, it’s your gut failing to move them into the bloodstream fast enough.

There’s one lever you can actually control.

Gut training. Repeatedly practicing higher carb intakes in training improves tolerance, which means more fuel actually gets used instead of causing problems.

Bottom line?
Fueling isn’t just about how much you take in, it’s about how much your gut can handle under race stress.

I dropped a marathon-pace block into the back half of my long run last weekend. Wind was up, two rolling hills sat in the middle, and my GPS pace was lying from minute one.

So I stopped chasing pace. I anchored to power.

My Critical Power right now is 317W. CP is the threshold where the type of fatigue you're fighting changes.

Stryd defines it as roughly the max power you can hold for 40 minutes. MP effort sits comfortably below it. That's the band I locked into.

Pace drifted with the terrain. Power held flat. That's the whole point.

The MP block inside a long run is the specific durability stimulus. It teaches your legs to hold marathon effort while already fatigued. That's late-race economy being built in real time.

Why it matters:

Next long run, drop a 4-6 mile MP block in the back half and pace it by power, not your watch.

👉 Try it on your next run