The driver of the vehicle, Tata steelworker Jamie Hitchings, was returning home after working a 6am to 6pm shift at the steelworks, the inquest heard.
Mr Hitchings said he had not seen Ms Martynova, who was dressed all in black and crossing in an “uncommon part of the road”, until immediately before the collision.
He said he slammed on his brakes before getting out of the car to help Ms Martynova.
Mr Hitchings then used some nearby cones to block off the road while attempting to get a response from Ms Martynova.
Giving evidence, PC Karl Painter, a forensic collision investigator for South Wales Police, said only one street light was illuminated.
He said the surface along the 50mph (80km/h) road was wet with “restricted visibility” due to the amount of rain falling, the darkness of the location, and the topography of the road.
Swansea council also confirmed to the police that street lighting was switched off at the time, as part of national energy reduction measures, which involved the switching off of lights after a risk assessment.
South Wales Police reviewed the circumstances and decided to take no further action.