Avoid strenuous or unusually intense exercise for at least 24 hours before blood testing.
Patients should therefore undertake their blood test following their usual level of activity, rather than immediately following unusually strenuous exercise or a hard training session.
Where accurate baseline or treatment-monitoring results are required, 48 hours without strenuous exercise may be preferable, particularly following exceptionally intense or prolonged exercise.
Normal light activity, such as routine walking, is generally acceptable.
Intense exercise can increase muscle-derived AST and can also produce transient changes in ALT and other liver-function markers, which may complicate interpretation.