The body produces fluids to protect itself from injury which is seen as swelling. For sprains in tissues, you apply ice packs to reduce the fluid build up for the first hours to stop the swelling, which is fluid that will have to be reabsorbed. Then apply heat.
Example, I was moving a goose, and its wing hit my knee bone hard, and it got a knob on it. 30 minutes of an ice pack and the swelling was reduced.
In other body injuries as spinal discs, which a friend just was limping past me today from being 59 years old and scooping snow in 20 below cold, the best solution is advil before the strain is noticed. Most back injuries are from the day before. Chemical interdiction helps stop the injury from complicating the next day. With that situation, you put heat on the affected area, along with gentle massage with rest.
For tears in ligaments, joints and connective tissues, heat, rest and advil is the treatment, as it usually takes weeks for that recovery, at least it has in my experience.
