Hundreds of Apple Watch 3 owners have reported that the device’s built-in activity tracker can be fooled by masturbating. 

According to one user on the Apple Forums called Harry Wunov, his Health app informed him that he had run ‘three and a half marathons’ after watching a single episode of Countdown.

He added: ‘I expected more from a £400 smartwatch if I am being honest.’

’The data is now shockingly inaccurate. It’s already told me that I have the metabolic rate of a blue whale.’

’An Apple Customer Service Rep has told me that it’s not a known problem, but I have been investigating the issue thoroughly for a whole week now.’

’If I go for a ‘stranger’ then nada, but every conventional hand shandy is convincing the tracker that I am a cross between Geoff Capes, Linford Christie and Forrest Gump.’