While swimming is a great workout, it's also one of the best activities for recovery. It improves the flexibility in your arms and shoulders, and surrounds your body with pressurization. Basically, the water can work like a compression suit to increase blood flow, which allows your body to filter your blood better. I talked to Bill Romanowski, who didn't miss a game for 15 years as a linebacker in the NFL. He said the pool is one of the things that allowed him to survive. He would always go to the pool and do either a form of pool training or swimming to flush lactic acids out of the body. Whether you have muscle damage from lifting or damage from impact, you're dealing with the same issues: Damaged tissue needs blood flow. It's really hard to pull anything, too. I mean, it's hard to hurt yourself swimming. There's just not enough resistance.