Stop running, sprinting, jumping, and stretching the hamstring aggressively
Rest the leg as much as possible for the first 48 hours
Apply ice for 15 to 20 minutes every 2 to 3 hours
Use a compression wrap or thigh sleeve for swelling support
Keep the leg elevated when sitting or lying down
Take over-the-counter pain relief only if safe for you and directed by the label
Do gentle pain-free range-of-motion movements only
Avoid heat, deep massage, and hard exercise in the first 48 hours
Use crutches if walking causes limping or significant pain
Return to activity only if you can walk, bend, and contract the muscle without pain
Seek medical care if pain is severe, swelling is large, bruising appears quickly, or you cannot walk normally