It is early treatment of acute soft tissue damage
•Rest
•Ice
•Compression
•Elevation

Rest: Reduce or stop using the injured area for 48 hours. Uou may need to stay off of it completely, a bit hard to do for a calf injury, I worn my trekking boots, which allow very little foot movement.

Ice: Put an ice pack on the injured area for 20 minutes at a time, best done every 4 hours last I read. Use a cold pack, ice bag, don't put ice directly onto the shin.

Compression: Compression of an injured calf may help reduce the swelling. Use bandages such as elastic wraps.

Elevation: keeps the blood out of the injured area.