Runner's Dilemma #26 — No More Drinking With the Club
Runner's Log | Runner's Dilemma #26
No More Drinking With the Club
There's a guy in my running club who's the same age as me.
After one of our meetups, he said, "Let's just grab a quick drink before we go."
That "quick drink" ran past 11pm, and I didn't get home until midnight.
Still groggy heading to work the next morning, my wife — who'd been holding it in — finally said something.
I just laughed it off.
For a while, I should probably just run and head straight home. Before I get in more trouble.
But then I got curious.
What does alcohol actually do to running?
I was still feeling it from the night before, and I had a 35km long run scheduled for 6am — I wanted to know if I should even do it.
So I asked AI.
What's Actually Happening Inside the Body
Turns out, a lot of the answer traces back to one basic principle.
The liver normally handles two important jobs: storing glycogen, and making new glucose whenever the body needs it.
Glycogen is the body's stored carbohydrate — its energy reserve. When you eat rice or bread, your body doesn't burn all of it right away; it converts some into glycogen and stores it in the liver and muscles. And the faster and longer you run, the more of this glycogen you burn through.
But when alcohol comes in, the liver starts processing it first. Studies have found that glycogen stores were lower after exercise in people who drank alcohol compared to those who didn't.
That said, researchers pointed out it isn't just alcohol's direct effect — reduced carbohydrate intake while drinking is also a major factor. At a drinking session you end up filling up on alcohol instead of food, so you're literally putting less fuel in the tank for the next day.
On top of that, drinking sessions usually run late, which means less sleep and less water.
Why "Fast Pace" and "Long Distance" Are Exactly the Wrong Combination
The faster your pace, the more you rely on glycogen. At an easy pace you burn more fat, but holding a goal pace means constantly burning through glycogen.
And glycogen isn't unlimited. The longer you run, the more your muscle glycogen stores drop.
Especially at a fast pace over a long distance, carbohydrate dependence rises, so running out of fuel becomes more of an issue in the later miles.
What runners often call "the 32km wall" is also thought to be related to this glycogen depletion and carbohydrate availability. Though these days, that alone isn't considered a complete explanation for late-marathon fatigue.
At a Glance
| What happens in the body | What it means for running |
|---|---|
| Glycogen recovery is impaired | Fuel is less ready for the next session |
| Hydration recovery may be impaired | More of a burden on long runs |
| Reduced muscle protein synthesis reported | May hinder post-run recovery |
| Reduced sleep quality | Next-day fatigue may increase |
| Hungover state | The same workout can feel much harder |
There was an interesting study, too. Researchers looked at people walking a 15.8km trail through the Samaria Gorge in Greece. Those who'd been drinking the night before and were hungover didn't actually take longer to finish than those who hadn't. But they reported feeling far more fatigued afterward.
So Should I Still Do the 35km Tomorrow?
Putting it all together,
With dehydration, poor sleep, and a hangover all stacking up at once, pushing through a hard workout carries more strain than usual. And 35km is already a demanding session on a good day, so doing it in this state is an even harder ask.
So tomorrow, instead of pushing through the full 35km, I should probably cut the distance or slow the pace.
AI is telling me to do that... and just then, my club president called.
that's when I'll really need to stop at "just a quick one."
Just like I originally meant to...
"Let's just grab a quick drink before we go."
References: Burke LM, Collier GR, et al. (2003). Effect of alcohol intake on muscle glycogen storage after prolonged exercise. Journal of Applied Physiology, 95(3), 983-990 · Parr EB, Camera DM, et al. (2014). Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis. PLOS ONE, 9(2), e88384 · Prentice C, Stannard SR, Barnes MJ (2015). Effects of heavy episodic drinking on physical performance in club level rugby union players. Journal of Science and Medicine in Sport, 18(3), 268-271 · Research on alcohol hangover and endurance performance (Samaria Gorge hikers) · Research on alcohol metabolism and the liver's suppression of gluconeogenesis and glycogen synthesis.
The interpretations here reference these findings from a runner's perspective and are not a substitute for medical advice.
