A dark and surreal drama set almost entirely inside the mind of a runner during a half-marathon.
Ruth's done this race before, she raised over £500 for a cause that's close to her heart.
This year, she'll double that, but only if she beats her best ever time.
It's the race of her life and she's in the lead, until her mind begins to wander.
She's discovered that her old school rival is also competing and, whilst she tries to keep focused on her running, her mind keeps coming back to her nemesis and the impact that girl had on Ruth's life.
As she nears the finishing line, Ruth's about to discover that her past isn't quite what she thought it was.
Using sound effects recorded at this year's Women's 10K in Bellahouston Park, Glasgow, Personal Best moves in and out of a runner's mind and gives us unique access into her weird and wonderful world.
Lesley Hart is an actress, journalist and keen runner.
This is her first radio drama.
Drama set in the mind of a runner attempting to beat her own record.