Ice can provide pain relief to sore muscles or burnt skin, but it should never be applied directly to your skin. Your skin turns red when you put ice on it because ice is so cold it damages the skin.
When you put ice on your skin, it causes an ice burn. This results in mild damage to the normal tissue on the exterior of your skin.
Symptoms of an ice burn include erythema, or reddened skin. The red skin might be tender to the touch, according to "Electrotherapy Explained."
Keep the red skin of an ice burn away from heat and direct sunlight. Most mild burns disappear after a day or two with no medical intervention.
- "Electrotherapy Explained"; Val Robertson, Alex Ward, John Low, Ann Reed; 2006.