What to notice
Write down the moment symptoms began and whether you had to stop. Previous injury, recent sprint sessions and return after a break are useful parts of the discussion.
Practical next steps
- Stop sprinting when sharp pain appears; do not test it with another maximal run.
- Avoid aggressive stretching of a newly painful hamstring.
- If a strain is diagnosed, follow the return-to-running plan rather than a fixed number of rest days.
When to get help
Get a sudden sharp thigh pain, bruising, weakness or difficulty walking assessed. A comfortable warm-up is not clearance to return after a suspected strain.