Factual error: After Samuel shoots himself he is lying on the floor next to the Glock he used. The slide is locked back even though he had only one round and no empty magazine in the gun. The slide will not lock back in this configuration.
Factual error: In the scene where they are first being chased (and where Pita writes down the license plate number), the plate on the other car has the number C5T K89. All DF plates for private cars and trucks have the format 123 ABC, as seen on the car driven by Creasy (845 PHY).
Answer: To cleanse his bullet wounds and to try and keep in shape.
Also, felt closer to Pita through her swimming.