Only use ice cubes in a plastic bag placed directly against the skin. A recyclable grocery bag works well. Don’t use any towels or material layers between the ice and your skin. Ice cubes against your skin will not "freezer burn" you. Chemical freezer packs are too cold, and they warm up quickly over time. Ice is best. When applying ice, realize that there are four sensations you will experience:

1: Very Cold!
2: More pain on the body part you’re applying ice to.
3: Throbbing
4: Numbness and Pain Reduction

These four stages can take about five or ten minutes to go through. Do not take the ice off your skin – endure the cold and pain periods, and keep the ice on you. Ice for thirty (30) minutes for medium-sized body parts (e.g. an elbow or knee). Large body parts, like hamstrings or lower backs can be iced for 45 minutes, while fingers can ice for about 20 minutes. You can ice multiple times per day, if needed, so long as you allow at least an hour rest between ice sessions. Ice times can be shortened by half if you compress the ice bag against the skin and rub/massage with the ice bag. This creates a deeper and longer lasting cooling effect.