You just finished exercising and your muscles are sore, but binging your favourite sitcom and waiting for it to recover might not be the best plan, instead try swimming.  This is gentle exercise that promotes recovery, works all the muscles in the body and alleviates muscle soreness with no additional strain on the joints. 
When going to swim, I recommend doing certain exercises (together called active hydrotherapy) rather than just swimming laps. These exercises could include simply walking in water across the shallow end, kicking your legs while you hold the edge standing near the pool wall, doing arm rotations under water. These exercises when done in water give gentle resistance improving mobility and relaxing your muscles.
So the next time you finish a lifting session, maybe go for a swim, but don’t just hop in without taking a bath!!