Hello Runner,

Welcome back to your weekly moment of endurance nutrition!

Happy Weekend!
How was your week?

My week was good.
In terms of work, I created and planned a lot of content. I attended an exciting event that explored strategies for maintaining well-being and balance as a founder or self-employed professional. It was a conversation with many insights and was great for networking.

In terms of training, I continue to follow my schedule. I woke up feeling a bit “so-so” on Wednesday; it seemed like I was going to get sick (I had a bad headache that day), and I ended up missing the running club. Anyway, that's life...

Today I want to talk about a topic that scares many runners, especially half-marathon and marathon beginners. The topic of the week is weight gain after a half-marathon and a marathon.

Runners often panic when they gain 1–3 kg after a half-marathon or marathon.
But here’s the truth: post-race weight gain is a normal physiological response to stress and inflammation. Let me break it down so it actually feels reassuring, not scary.

Let’s start with something important: your body is not going crazy, or you’re not abnormal.
Quite the opposite — it’s doing exactly what it’s supposed to do after a massive effort.

During the last weeks of training for a half or full marathon, your body becomes a machine that constantly adapts, repairs, and stores energy. 

Going through a training cycle for a half or full marathon is not a simple process, and the body is not used to it. Especially on peak weeks, there’s a gradual increase in inflammation. Not bad inflammation, but the kind that comes from consistently loading the muscles.

Your body gets stronger, yes, but it also stays in this “constant repair mode,” holding a bit more water, salt, and glycogen than usual.

This is why many runners find they’re a little heavier during peak training and the week after a race.

1. Residual Inflammation = water retention
When you run for 21 or 42 km, you cause thousands of micro-tears in your muscle fibers. It’s normal — it’s part of the sport.
But micro-tears → inflammation → water retention.
Your muscles literally “hold onto” water to repair themselves.

2. Glycogen stores refilling
Before and after the race, you load up on carbs.
Glycogen binds to water (about 1 g glycogen = 3 g water).
So when your muscles restock glycogen after the race?
Yes — the scale moves.

3. Sodium fluctuations
Between salty race-day broths, gels, electrolyte drinks, and sometimes mild dehydration, your body often retains extra sodium and water. 

4. Stress hormones — especially cortisol
Long efforts spike cortisol.
Cortisol makes the body retain water, increases appetite, and sometimes slows digestion.

5. No post-race adjustment in terms of energy expenditure
During the race training cycle, you’re used to fuel to meet your daily and training needs. After the race, the energy needs change, but many runners continue to eat as they did during half or full marathon training.

6.“Post-race entitlement syndrome” 
During the race cycle, there are many food restrictions and even cognitive restrictions. That thought of “I can't do this, or I can’t eat this,” and after the race is over, runners think they deserve everything and end up eating more than they should. And they generally tend to eat foods that are higher in fat and sugar, as well as alcohol.

Put all this together and you get one simple message:
This is not body fat. It’s the temporary cost of doing something incredible.

If your weight goes up after a race, you’re not going backwards.
You’re recovering.
Your body is healing.
And with the right strategies — especially the nutrition ones — you can help things settle back down in a matter of days.

Once runners understand this, they stop panicking and start supporting their recovery intentionally.

Tell me: have you ever gained weight after a race? What surprised you the most?

Reply to this email — I read every message.

Any questions or something you would like to share, drop me an email

Wishing you a great weekend and week ahead!

Here’s to health and good runs⚡️

Ana Paula Alonso