Eva Hermann

⚡2:31 marathoner | Certified running coach for amateur runners. Ended pro career in 2013. Resumed training in 2021 as a masters runner. Goal: sub-2:40 marathon

[Eva Hermann @RunwithEva]

Something about me 🙂
I always loved sports, but couldn’t find myself in any until my university time. I have chosen to go for a psychology degree in order to understand myself better. 1/9

[Eva Hermann @RunwithEva]

@Brady_H What’s your personal opinion?

[Eva Hermann @RunwithEva]

@Brady_H @DailyTrolling A, got it.

[Eva Hermann @RunwithEva]

@Brady_H What is your height? Need to show it one of my runners of your level to convince him to eat more. 😄

[Eva Hermann @RunwithEva]

@Brady_H I can agree. Since water with magnesium already exists.

[I��igo San Millán @doctorinigo]

30 years ago I was working with elite athletes and drawing training zones on paper based on blood lactate curves.
No substrate data. No indirect calorimetry. Just the conviction that something metabolically distinct was happening at each intensity — and that Zone 2 was where the most important adaptation was taking place.

In 2005 I began adding fat and carbohydrate oxidation rates to the picture, and what the substrate data revealed confirmed what the lactate curves had been suggesting all along: each intensity represents a distinct metabolic state, not just a point on a continuum of effort.

That work became the Metabolic Map in 2013. Then the metabolic flexibility paper with George Brooks in 2018. And now the updated 2026 framework, which maps four metabolic states onto classical threshold models and asks a question the older models never quite posed:
Is the system in optimal metabolic balance, or is it drifting away from it?

Lactate turns out to be the best real-time proxy we have for answering that question. It tracks metabolic equilibrium, the onset of drift, and the progression toward overload better than any other single variable we can measure in the field.

Thirty years of work. One molecule. One central question.

My last substack article

https://t.co/hvNuIVnH6b

[Alan Couzens @Alan_Couzens]

Which "zone 2" are you talking about?

It drives me a little crazy when folks ask "what do you think about zone 2?"

Because, they are often, talking about different things.

A quick 🧵

[Howard Luks MD @hjluks]

Running and Knee Osteoarthritis...
I treat a lot of runners... one of the most common questions I get is whether running is bad for your knees. Their friends tell them to stop running... online influencers occasionally scream it into the ether. Your friends are not right.

After 30 years in practice and a continuous, and pretty thorough look at the research, I can tell you that the evidence consistently points in the opposite direction. Running, at recreational levels, appears to be protective against knee osteoarthritis, not harmful.

Let's get into this...

[Tom Coughlin @tecoughlin]

Does protein intake influence low-energy availability symptoms?🪫

This new study recruited healthy active females (n = 9) and males (n= 10) to complete 3 x 5-day dietary conditions

1️⃣ Adequate energy availability (AEA: 45 kcal/kgFFM/day)

2️⃣ Low energy availability (LEA: 15 kcal/kgFFM/day)

3️⃣ Low energy availability with protein intake matched to AEA (LEA-P: 15 kcal/kgFFM/day)

The difference in protein intake between LEA and LEA-P was 0.45 g/kg and 1.5 g/kg, respectively 🍗

Metabolism, performance and subjective responses were assessed pre- and post-interventions 🔍

Results 📊

🔥 Both the LEA and LEA-P diets induced a shift towards increased fat oxidation at rest, but not during exercise

⚡️ Wingate performance declined only in the LEA-P trial compared to AEA

👉 This was likely due to reduced carbohydrates the LEA-P trial (to accommodate for higher protein)

🧠 During both LEA and LEA-P, participants generally reported negative experiences during both calorie-restricted trials, including hunger, fatigue, weakness and frustration

🙋‍♂️ Symptoms appeared more pronounced in males during the LEA trial

Higher protein intake intake during LEA does not appear to significantly effect symptoms ❌

This study also highlights the importance of carbs for performance even in low energy conditions ‼️

Carbs carry performance, even when calories can’t.

Reference:

https://t.co/Wkkmbk6Dj0

Subscribe to Performance Nutrition Digest FREE to receive your daily study breakdown, straight to your inbox or via the Substack app 📥

https://t.co/eiomLjpPt2

Performance Nutrition Digest is powered by Healthspan Elite⚡️

https://t.co/x7WMHaanT4

[Jonah Rosner | Elite Sport Scientist @jonisportsci]

Endurance athletes appear to need more protein on recovery days than on training days. Witard, Hearris, and Morgan reviewed a decade of metabolic studies in Sports Medicine (2025).

The IAAO data (a modern method for estimating daily protein need) point to these targets in endurance-trained men:

About 1.8 g/kg on a standard training day. About 1.95 g/kg on a low-carb training day. More than 2.0 g/kg on a recovery day.

Habitual intake sits around 1.5 g/kg. The RDA for sedentary adults is 0.8 g/kg.

Why recovery days run highest: endurance training damages contractile fibres, repair continues for over 24 hours after a session, and amino acids are oxidised as fuel during exercise (about 6% of total energy cost). The repair bill is paid after the work, not during it.

Per-meal dose after a hard session: about 0.5 g/kg appears maximally effective for repairing contractile fibres. Roughly 35 g for a 70 kg runner, and about twice the post-strength dose. This is a single dose-response study with a wide CI (0.26 to 0.72 g/kg). Treat it as emerging.

One caveat: no IAAO study has been done in female endurance athletes, and none in masters over 65. The 1.9 g/kg luteal-phase figure is extrapolated from team-sport data.

Carbohydrate remains primary for endurance fuel. Protein supports recovery and adaptation alongside it.

Huge thanks to Witard, Hearris, and Morgan for this work.

Witard et al. (2025), Sports Medicine.

https://t.co/nlEghAfqb4

[Iñigo San Millán @doctorinigo]

VO₂max can improve with exercise training in metabolically unhealthy individuals. But VO₂max can improve through mechanisms that have limited relationship to the core cellular dysfunction driving disease. For example, cardiac output can increase while mitochondrial function and cellular bioenergetics remain impaired.

Lactate testing represents cellular adaptations to exercise and it is the best indicator for mitochondrial function that we have nowadays.

https://t.co/coBII673Rs

[Alan Couzens @Alan_Couzens]

Let me dump some carbs on you...

Someone said yesterday that thinking about CHO intake in terms of stores, output and "bonking" is the "old way" of looking at carbs in sport.

That pissed me off.

So, let's start with...

Only those with a bullet-proof basic understanding can have an advanced understanding.

Put another way, he couldn't tell me why this is the case. So, let me tell you why this is that case...

The error in thinking of a carbohydrate/glycogen "reservoir" comes largely in the sense that the reservoir isn't one tank.

We have...
Tank 1: Liver Glycogen
Tank 2-2,000,000 Muscle Glycogen

That is, every muscle fiber has its own little tank. So, in terms of glycogen depletion, while a significant drop in liver glycogen is obvious - the typical "bonk"...

Drops is muscle glycogen are far more subtle...

They manifest as progressive transition from more economical fibers to less economical. So, over the course of the race, pace for a given O2 uptake progressively decreases.

*Assuming CHO makes it across the gut wall to the blood*...

High levels of exogenous intake can offset this progressive depletion of more economical fibers & keep the pace high for a give O2 uptake over longer periods of time.

This is why, again, assuming good levels of clearance from the gut, high CHO intake can have a small, but meaningful impact on the pace that can be held late in a race.

TLDR...
- A liver glycogen bonk is obvious.
- Muscle glycogen depletion is subtle.
- Exogenous CHO can offset glycogen depletion (to an extent) & help to maintain pace for longer.

But....
1/ The size of the engine determines fuel needs.
2/ You can only use what you can clear (& if you can't clear it, there's a timebomb jostling around in your gut - just waiting to go off)

[Eva Hermann @RunwithEva]

@ValMThatcher @Alan_Couzens No rush. He is only 14 y.o. Foundation should come first.

[Eva Hermann @RunwithEva]

@zbitter I will say it here again: Richard Ringer 2:04, 60g/h. Don’t get crazy.

[Eva Hermann @RunwithEva]

@zbitter People get crazy about carbs on both extremes. We had a conversation with Richard Ringer (ran 2:04 in Boston) in March. He takes 60 g/h on the marathon. I am with @Alan_Couzens here - improve your fat oxidation then you will be less dependent on carbs and metabolically healthy.

[Eva Hermann @RunwithEva]

@RunSensible @Alan_Couzens Let me share my data. RHR 45-48. HRmax 186. LT2 172, LT1 162. Most of my easy runs are between 130 and 140.

[Howard Luks MD @hjluks]

Tendon pain is the most common reason people come to see me.
Most of it is self-inflicted — from doing too much, too soon, or from doing too little for too long.
Let's review what most people (including many doctors) don't understand about why tendons hurt and how to fix them. 🧵

[Eva Hermann @RunwithEva]

@Alan_Couzens This is what we did after the marathon recovery every half a year. 3-4 weeks easy mileage and Gym 3xweek. I never had any injuries. This is what I didn’t do enough over the past years when it’s even more important approaching 45y.o.

[Andy Galpin, PhD @DrAndyGalpin]

Perform with Dr. Andy Galpin is back.

New episode: How to Build a Strong Core & Abs

0:00 Core Training Myths
4:22 Why We Train Abs Wrong
7:27 Abs vs Core Explained
11:17 Look Feel Perform Goals
15:04 How Core Muscles Work
20:26 Stability and Anti Movement
24:00 Do Abs Need Daily Training
29:12 Spinal Safety and Crunches
31:37 Sponsor Eight Sleep
33:08 Testing Core Strength
41:42 Interpreting Test Results
47:02 Choosing Core Exercises
50:18 Isolation vs Compound Core
52:31 Contraction Intensity Rules
53:23 Size Principle Explained
56:16 Loading the Core Safely
1:00:14 Core Moves by Pattern
1:06:35 Program by Muscle Groups
1:08:01 Abs for Aesthetics
1:15:47 Aesthetic Programming Split
1:18:49 Core for Performance
1:21:15 Core for Back Health
1:24:17 Sample Week Template
1:29:22 Five Step Progression
1:35:54 Exercise Order Priorities
1:36:56 Rapid Fire Q and Belts
1:42:35 Final Wrap and Support

Includes paid partnerships.

[Eva Hermann @RunwithEva]

@Alan_Couzens Same here. My own running career was destroyed because my coach didn’t hold me back. I was young and stupid to figure out myself. I have also seen so many young gifted athletes finishing at 20 years old because they were completely burned down.