Alcohol after training mainly slows your recovery, rather than today's strength. Above roughly 1 gram of alcohol per kilo of body weight, which for someone of 80 kilos comes to about six standard drinks, researchers measure the clearest effects on muscle recovery and sleep.
There is a second effect that is discussed almost nowhere. Hard training disturbs exactly those blood values people use to read off alcohol damage.
Below you can read what alcohol does to your performance and recovery, and why your own blood result can mislead you.
What does alcohol do to your sports performance?
On the day itself you mainly notice coordination and endurance. Alcohol slows your reaction time and disturbs fluid balance, because your kidneys pass more fluid. Strength across a single repetition often stays reasonably intact at small amounts, but the quality of a whole session drops.
It is rarely about that one set.
It is about the sum: slightly less sleep, slightly more dehydration, slightly less appetite for it. Across weeks that translates into less training volume.
Why does alcohol slow your recovery?
Recovery largely happens in your sleep, and alcohol disturbs the deep sleep phases in particular. You fall asleep faster and wake less rested. Research also indicates that alcohol can slow the production of new muscle protein after a session.
That effect stacks up for people who train often.
Someone training five times a week and drinking on three evenings recovers structurally below their potential. Why alcohol leaves you less rested is covered in more detail in alcohol and sleep.
From how much alcohol do you notice it?
The clearest effects on recovery are measured above roughly 1 gram of alcohol per kilo of body weight. For someone of 80 kilos that is broadly six standard drinks in one evening. Below that amount the effects are smaller and vary a lot per person.
That is not a safe limit, and we do not mean it as one.
The Dutch Health Council still advises that any amount of alcohol can be harmful. The 1 gram per kilo is a research threshold, not a recommendation.
Why can training distort your blood values?
Hard training leaks muscle proteins into your blood, and some of those are reported as liver values. CK rises sharply after a hard or unfamiliar session, and ASAT rises with it because it also sits in muscle tissue. An athlete can therefore see a result that looks like liver damage.
| Marker | Responds to alcohol | Responds to hard training | What that means |
|---|---|---|---|
| CK | barely | strongly, for days afterwards | a high CK points to muscle load first |
| ASAT | yes, with prolonged use | yes, also sits in muscle | not to be interpreted on its own |
| ALAT | yes, with prolonged use | limited | more liver-specific than ASAT |
| Gamma-GT | yes | barely | less sensitive to training noise |
| CDT (%CDT) | yes, with a pattern | no | the least disturbed by sport |
For an athlete that is a useful distinction, and I've seen this confusion more here than in any other group. Gamma-GT and CDT are barely influenced by training, ASAT and CK are.
What gamma-GT does and does not say is covered in gamma-GT too high.
When is the best moment to have blood taken?
If you want to assess your values without training noise, it can help to avoid a hard or unfamiliar session for a few days before the measurement. CK often peaks 24 to 72 hours after the load. A quiet week gives a cleaner picture than the day after a marathon.
Picture this: you run a 21 km half marathon on Sunday and have blood taken at 8am on Monday.
Your CK can sit above 1,000 U/l and your ASAT around 60 U/l, while you drank nothing that weekend. Your gamma-GT and %CDT stay normal in that same sample. Someone doing that measurement on Friday sees a much calmer picture.
So always discuss a deviant result with your GP, and mention how you have been training.
Does it matter when you drink around a race?
The timing counts, mainly through your sleep and your fluid balance. Alcohol on the evening before an effort disturbs deep sleep exactly when you need it. Afterwards it competes with the recovery from that same session.
So the evening after is not without consequences.
Many athletes therefore plan their drinks on days without hard training. That changes nothing about the health risk, but it does limit the brake on their recovery.
If you specifically want to know your CDT value, an alcohol CDT test can quantify that, and that value is insensitive to your training week.
What strikes me most with athletes: they are alarmed by a liver value that mainly reflects their training. The marker is not wrong, the context is missing.
So have your blood taken after a quiet period, and bring your training schedule to the conversation with your GP.
Every blood test result at Zuivertest includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.
Sources
- Gezondheidsraad, advice on alcohol: any amount of alcohol can be harmful (accessed July 2026).
- RIVM, Leefstijlmonitor, alcohol use among adults, 2025 figures.
- Thuisarts.nl, "Ik drink vaak alcohol" (accessed July 2026).
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