Hurt shoulder (rotator?) from lifting. can't lift arm. should i ice or heat?

See your doctor: Ice will help keep the swelling and pain down. The important question is what is wrong with your shoulder. If the pain does not go away in a week or so, see your doctor to get examined and possibly have tests to determine what was damaged. Hope this helps!

Ice vs heat: Hi, it depends all on you have muscle spasm and tension or inflammation in the shoulder, muscle spasm gets better with heat while inflammation gets better with cold pack, try both and see which one feels better.

Acute injury: Ice is best to help reduce swelling and inflammation initially. Some people find that heat helps increase motility and relieves pain afterwards, especially after periods of rest such as sleep. NSAIDs such as Motrin or Advil (ibuprofen) every 6-8 hours are also frequently advised.

Shoulder: With injuries the first thing to do is to ice it in the first 12 hours. This helps with swelling, but also has an anti inflammatory effect too!

First ice then heat: With an acute injury, there is trauma to local blood vessels with resulting leaking of fluid to surrounding tissue. Ice applied immediately after an injury can limit the swelling of the damaged tissue area. After 18 - 24 hours of ice application, heat is beneficial to help the local follow of needed blood product to help the repair process to the damaged tissue and pain relief.