AST (Liver)
AST is the second core liver enzyme on a standard panel, though it's also released by damaged muscle tissue — which matters for anyone training hard.
Reference range
Watch points
- Critical: at or above 200 U/L
- High: at or above 100 U/L
- Borderline: at or above 60 U/L
Same thresholds apply to men and women in this table.
Why hard-training athletes watch it
Because AST is also a muscle-damage marker, a hard leg day or a new training block can elevate it on its own — reading AST next to ALT (which is liver-specific) helps tell muscle soreness apart from an actual liver signal.
When to retest
Avoid drawing within 48–72 hours of an unusually hard session if you're trying to isolate a liver signal from a muscle-damage signal.
Talk to your clinician
Review hepatotoxic supports and alcohol with your clinician, and ask about a recheck in a few weeks. If ALT is normal but AST is elevated, recent training is the most likely explanation — still worth mentioning to your clinician, especially if it persists after a rest period.
Related reading
SomaZeus tracks ast (liver) alongside every other panel, your training, and your nutrition on one timeline — so you see the trend, not just the number. Get your first read →
Reference source: NIH MedlinePlus
This article is for education only and is not medical advice. Reference ranges vary by lab and population — always interpret your own results with a qualified clinician.