What is the best treatment for a pulled my hamstring doing the 100m sprint?

RICE: You should start with rice as a home treatment. After 48-72 hours you may switch to heat (instead of ice). As your pain starts to subside you may add stretching as tolerated, and massage. Once pain is gone, then gently return to activity as your strength and flexibility may need time to recovery after the injury, and you don't want to further injure yourself by attempting to go "all out" to fast.

Hamstring: Rest, light compression, ice, stretching can all be of benefit. Guided exercise program from a physical therapist can be helpful to rehabilitate your injury. There has been some interest in platelet rich plasma injections in speeding the recovery as well.