The best NASCAR cup race of the season is Saturday night at Bristol Motor Speedway (TNT - 7:30pm Eastern Time.) Food City, one of the track's sponsors, has built a huge motorized shopping cart that runs around the track before the race.
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.